BENZOYL CHLORIDE ANHYDROUS

Benzoyl Chloride Anhydrous is a moisture-sensitive aromatic acyl chloride used as a highly reactive benzoylating agent and chemical intermediate in the manufacture of benzoyl peroxide, pharmaceuticals, dyes, pigments, fragrances, agrochemical intermediates, specialty resins, surfactants and other benzoyl derivatives. Benzoyl Chloride Anhydrous has CAS Number 98-88-4, EC Number 202-710-8, molecular formula C7H5ClO and molecular weight approximately 140.57 g/mol. Benzoyl Chloride Anhydrous is normally a colorless to pale-yellow, clear, fuming liquid with a pungent lachrymatory odor, boiling point around 197.2°C, melting point around -1°C, density about 1.21 g/cm³ and closed-cup flash point around 72°C. The defining handling requirement is strict moisture exclusion because Benzoyl Chloride Anhydrous reacts with water to form Benzoic Acid and hydrogen chloride, generating heat and corrosive acidic fumes. The anhydrous designation therefore describes a moisture-controlled commercial grade rather than a different molecular substance, and the exact water specification must be taken from the current product specification and batch COA rather than assumed from a universal industry limit.

PRODUCT IDENTITY

Chemical Name: Benzoyl Chloride
Product Designation: Benzoyl Chloride Anhydrous
CAS Number: 98-88-4
EC Number: 202-710-8
EU CLP Index Number: 607-012-00-0
PubChem CID: 7412
Molecular Formula: C7H5ClO
Condensed Formula: C6H5COCl
Molecular Weight: Approximately 140.57 g/mol
IUPAC Name: Benzoyl chloride
Chemical Class: Aromatic acyl chloride / acid chloride
Functional Group: Acyl chloride
Physical Form: Liquid
Appearance: Colorless to pale-yellow clear liquid
Odor: Pungent, irritating, lachrymatory
Melting Point: Approximately -1°C
Boiling Point: Approximately 197.2°C at 1013 hPa
Density at 20°C: Approximately 1.21 g/cm³
Refractive Index: Approximately 1.553 at 20°C in widely cited reference data
Vapor Pressure at 20°C: Approximately 0.5 hPa
Relative Vapor Density: Approximately 4.88 relative to air
Flash Point: Approximately 72°C closed cup in widely used safety data
Explosive Range: Approximately 2.5-27 vol% in air in historical safety references
Primary Function: Benzoylating agent and reactive chemical intermediate
Primary Industrial Use: Manufacture of benzoyl peroxide and other benzoyl derivatives
Principal Reactivity: Rapid acylation of alcohols, phenols and amines; hydrolysis by water
Hydrolysis Products: Benzoic Acid and hydrogen chloride
Moisture Sensitivity: High
Anhydrous Grade Meaning: Moisture-controlled Benzoyl Chloride suitable for water-sensitive synthesis and processing
Water Specification: Product-specific; no universal water-content limit should be assigned without the current TDS or COA
Typical High-Purity Commercial Assay: Approximately 98-99% or higher depending on grade
Transport Identification: UN 1736
Transport Hazard Class: Class 8, Packing Group II under widely used transport classification
Storage Principle: Dry, tightly closed, moisture-protected storage; inert-gas handling is preferred where the process requires strict anhydrous conditions

SYNONYMS

Benzoyl Chloride, Benzoyl Chloride Anhydrous, Anhydrous Benzoyl Chloride, Benzenecarbonyl Chloride, Benzene Carbonyl Chloride, Benzoic Acid Chloride, Benzoic Acid, Chloride, Benzoylchloride, Benzoylchlorid, BzCl, Benzene Carboxylic Acid Chloride, Benzenecarboxylic Acid Chloride, Benzoyl Chloride 98-88-4, Benzoyl Chloride CAS 98-88-4, Benzoyl Chloride EC 202-710-8, Benzoyl Chloride C7H5ClO, C6H5COCl, Benzoyl Halide, Aromatic Acyl Chloride, Aromatic Acid Chloride, Benzoylating Agent, Benzoylation Reagent, Benzoyl Chloride Reagent, High-Purity Benzoyl Chloride, Dry Benzoyl Chloride, Moisture-Sensitive Benzoyl Chloride, Water-Sensitive Benzoyl Chloride, Benzoyl Chloride Intermediate, Benzoyl Chloride for Synthesis, Benzoyl Chloride Liquid

WHAT IS BENZOYL CHLORIDE ANHYDROUS?

Benzoyl Chloride Anhydrous is the moisture-controlled commercial form of Benzoyl Chloride used where hydrolysis must be minimized during storage, transfer and reaction.
The molecule is an aromatic acid chloride derived conceptually from Benzoic Acid by replacing the hydroxyl group of the carboxylic acid with chlorine.
This substitution converts the relatively stable carboxylic acid into a highly reactive acylating reagent.
Benzoyl Chloride Anhydrous reacts readily with oxygen- and nitrogen-containing nucleophiles and is therefore widely used to introduce benzoyl groups into alcohols, phenols, amines and other reactive substrates.
The material is chemically identical to ordinary Benzoyl Chloride with the same CAS Number and formula; the term anhydrous refers to controlled moisture rather than a distinct chemical species.
The exact moisture requirement varies by customer process and commercial grade and must be confirmed by the current product specification.

ANHYDROUS GRADE

Anhydrous Benzoyl Chloride is required when water would consume reagent, generate hydrogen chloride or interfere with product selectivity.
Even small amounts of moisture can reduce effective acyl chloride content because each mole of water can hydrolyze reactive Benzoyl Chloride.
Hydrolysis forms Benzoic Acid and hydrogen chloride.
Benzoic Acid can remain as an impurity in the organic phase or precipitate depending on temperature and solvent system.
Hydrogen chloride can corrode equipment, protonate amines, change catalyst behavior and alter downstream purification.
For high-sensitivity synthesis, moisture should therefore be controlled in the raw material, solvent, reactor, transfer lines and receiving vessel.

WHY WATER CONTENT MATTERS

Water content is one of the most important quality parameters for Benzoyl Chloride Anhydrous.
Moisture directly consumes active acyl chloride.
Hydrolysis increases Benzoic Acid content and releases hydrogen chloride.
The resulting acid can shift reaction stoichiometry, create corrosion, increase salt formation and reduce yield.
A process using expensive or sensitive amine or alcohol substrates can therefore be strongly affected by even modest hydrolysis.
Because commercial requirements vary, the correct water limit should be defined contractually through the current product specification and batch COA.

HYDROLYSIS

Benzoyl Chloride reacts with water to form Benzoic Acid and hydrogen chloride.
The reaction is exothermic and can release corrosive hydrogen chloride fumes.
Bulk contact with water should therefore be avoided during storage, transfer and spill response.
Hydrolysis can occur from atmospheric humidity as well as direct liquid water.
Opened containers should be resealed promptly or handled under a dry inert atmosphere where practical.
Wet equipment should not be charged with Benzoyl Chloride Anhydrous.

PHYSICAL PROPERTIES

Benzoyl Chloride Anhydrous is normally a clear, colorless to pale-yellow liquid at room temperature.
The melting point is around -1°C, so the product remains liquid under ordinary storage conditions unless exposed to unusually low temperature.
The normal boiling point is approximately 197.2°C.
Density is approximately 1.21 g/cm³ at 20°C.
The vapor pressure is low at room temperature compared with common solvents, but the vapor is highly irritating and toxic by inhalation.
The product fumes in humid air because hydrolysis produces hydrogen chloride.

BOILING POINT

Benzoyl Chloride has a normal boiling point around 197.2°C.
The relatively high boiling point supports distillation and purification under controlled industrial conditions.
Vacuum distillation can reduce thermal exposure.
Heating should be performed in dry, corrosion-resistant equipment with suitable ventilation and containment.
The product should not be heated unnecessarily because higher temperature increases vapor generation and exposure risk.

MELTING POINT

Benzoyl Chloride melts at approximately -1°C.
The low melting point means it is generally handled as a liquid in normal industrial environments.
Very cold storage can cause partial solidification or crystallization.
Material that has solidified should be warmed only by a controlled approved method and never with open flame.
Uniform temperature should be restored before sampling or metering.

DENSITY

Benzoyl Chloride has a density of approximately 1.21 g/cm³ at 20°C.
The liquid is therefore denser than water.
Density is useful for inventory calculations and volumetric transfer calibration.
Reaction stoichiometry should preferably be controlled by mass when high precision is required.
Product-specific density on the COA should be used when a narrow transfer calculation is needed.

VAPOR PRESSURE

The vapor pressure of Benzoyl Chloride is approximately 0.5 hPa at 20°C in widely cited reference data.
Although this is low compared with volatile solvents, the vapor is hazardous because Benzoyl Chloride is toxic by inhalation and highly irritating.
Fuming can become visible when vapor encounters atmospheric moisture.
Local exhaust and closed transfer are therefore important even when bulk evaporation appears slow.

FLASH POINT

Widely used safety data report a closed-cup flash point of approximately 72°C.
Some commercial references report different values because test methods and product conditions vary.
The current product-specific SDS should therefore control formal fire classification.
Benzoyl Chloride should be treated as a combustible reactive liquid and kept away from ignition sources and uncontrolled heating.
Fire response is complicated by the fact that water also reacts with the acid chloride.

ACID CHLORIDE REACTIVITY

Benzoyl Chloride is an acid chloride and is much more reactive than Benzoic Acid or most benzoate esters.
The carbonyl carbon is strongly electrophilic because chlorine is an effective leaving group.
Nucleophiles can therefore attack the carbonyl center and displace chloride.
The resulting benzoyl derivatives include esters, amides, anhydrides and other acyl-transfer products.
Hydrogen chloride is often formed directly or indirectly during these reactions.
Base, catalyst or hydrogen-chloride scavenger selection is therefore an important part of process design.

BENZOYLATION

Benzoylation is the introduction of a benzoyl group into an organic molecule.
Benzoyl Chloride is one of the most widely used reagents for this transformation.
Alcohols can be converted into benzoate esters.
Phenols can be converted into aromatic benzoate esters.
Primary and secondary amines can be converted into benzamides.
Benzoylation is used in manufacturing, protecting-group chemistry, analytical derivatization and intermediate synthesis.

SCHOTTEN BAUMANN REACTION

Benzoyl Chloride is a classic reagent in Schotten-Baumann benzoylation.
An amine or alcohol is reacted with Benzoyl Chloride in the presence of aqueous or nonaqueous base that neutralizes hydrogen chloride.
The method is especially useful for preparing benzamides and benzoate esters.
When an anhydrous grade is specified, the goal is usually to maintain control before the reagent is deliberately introduced into the selected reaction environment.
The reaction design should account for exotherm, gas or acid evolution, phase transfer and salt formation.

APPLICATIONS

Benzoyl peroxide manufacture
The largest established industrial use of Benzoyl Chloride is as a raw material for benzoyl peroxide. Controlled reaction with peroxide chemistry produces the diacyl peroxide used as a polymerization initiator, curing agent and specialty oxidizing ingredient.

Polymerization initiator intermediates
Benzoyl Chloride is used to make benzoyl peroxide and related benzoyl peroxide formulations used to initiate free-radical polymerization.

Pharmaceutical intermediates
Benzoyl Chloride is a versatile benzoylating reagent in pharmaceutical synthesis and can be used to produce benzamide, benzoate and protected intermediates.

Active pharmaceutical ingredient synthesis
Benzoyl Chloride can introduce benzoyl functionality into appropriately designed API routes where the process is validated for impurity control and residual reagents.

Benzamide synthesis
Primary and secondary amines can react with Benzoyl Chloride to form benzamides.

N-benzoylation of amines
Benzoyl Chloride is widely used to acylate amine nitrogen in organic synthesis.

O-benzoylation of alcohols
Alcohols can be converted into benzoate esters using Benzoyl Chloride under controlled reaction conditions.

O-benzoylation of phenols
Phenolic hydroxyl groups can be benzoylated to form aromatic benzoate esters.

Protecting-group chemistry
Benzoyl groups are used as protecting groups for alcohols, phenols and amines in multistep organic synthesis.

Carbohydrate chemistry
Hydroxyl groups in sugars and carbohydrate intermediates can be protected through benzoylation where the synthetic route requires ester protection.

Nucleoside chemistry
Benzoyl protection is used in selected nucleoside and nucleotide synthesis routes to control reactive amino or hydroxyl groups.

Peptide-related synthesis
Benzoyl derivatives can be used in specialized amino-acid and peptide chemistry as protecting or modifying groups.

Dye intermediates
Benzoyl Chloride is an established raw material for dye and pigment intermediates.

Pigment intermediates
Benzoylation can modify aromatic and amine-containing intermediates used in pigment synthesis.

Fragrance intermediates
Benzoyl Chloride is used in the manufacture of fragrance-related benzoate esters and aromatic intermediates.

Perfume intermediates
Benzoate ester and aromatic acylation chemistry connects Benzoyl Chloride with perfume and fragrance manufacturing.

Benzyl benzoate synthesis
Benzoyl Chloride can react with benzyl alcohol to produce benzyl benzoate under suitable conditions.

Benzoate ester manufacture
Methanol, ethanol, propanol, butanol and other alcohols can be benzoylated to produce benzoate esters.

Specialty ester synthesis
Benzoyl Chloride is used to produce high-value benzoate esters where direct esterification of Benzoic Acid is too slow or unsuitable.

Surfactant intermediates
Benzoyl Chloride is used in selected surfactant and specialty-amphiphile syntheses where aromatic acylation is required.

Resin intermediates
Benzoyl Chloride can be used in specialty resin modification and synthesis of benzoylated intermediates.

Coating intermediates
Benzoyl derivatives made from Benzoyl Chloride can be used in coating-resin, additive and curing-agent chemistry.

Agrochemical intermediates
Benzoyl Chloride is a chemical intermediate in selected herbicide, pesticide and specialty agrochemical manufacturing routes.

Herbicide intermediates
Benzoylation chemistry is used in the synthesis of selected herbicidal active ingredients and intermediates.

Pesticide intermediates
Selected pesticide synthesis routes use Benzoyl Chloride or substituted benzoyl chlorides as reactive acylating reagents.

Fine chemicals
Benzoyl Chloride is a general fine-chemical intermediate for aromatic acyl-transfer chemistry.

Specialty chemicals
High-purity Benzoyl Chloride Anhydrous is used in water-sensitive specialty synthesis where impurity and moisture control are important.

Analytical derivatization
Benzoyl Chloride is used to derivatize alcohols, phenols and amines before chromatographic analysis.

Liquid chromatography derivatization
Pre-column benzoylation can increase ultraviolet response and chromatographic retention of polar analytes.

LC-MS derivatization
Benzoyl derivatives can improve detectability of selected analytes in liquid chromatography-mass spectrometry workflows.

Phenol analysis
Phenolic analytes can be converted into benzoate derivatives for improved chromatographic measurement.

Biogenic amine analysis
Benzoylation of amines can improve extraction, retention and detection in analytical methods.

Organic analysis
Benzoyl derivatives have long been used to characterize and identify compounds containing reactive hydroxyl or amino groups.

Research synthesis
Benzoyl Chloride is a standard reagent for organic and medicinal chemistry research.

Benzoyl protecting-group installation
Benzoyl Chloride Anhydrous is useful when moisture-sensitive benzoylation conditions are required to minimize reagent loss and side reactions.

Acid chloride chemistry
Benzoyl Chloride serves as a model and practical reagent for nucleophilic acyl substitution chemistry.

Benzophenone-related intermediates
Benzoyl chemistry can contribute to synthesis routes for benzophenone and substituted benzophenone intermediates.

Photoinitiator intermediates
Selected photoinitiator and photosensitive-material routes use benzoyl-containing intermediates produced through acyl chloride chemistry.

Polymer-additive intermediates
Benzoyl derivatives are used in selected stabilizer, initiator and specialty polymer-additive synthesis routes.

Laboratory benzoylation
Benzoyl Chloride Anhydrous is a standard reagent for small-scale ester and amide formation where dry conditions improve reproducibility.

Process chemistry
The reagent is used in scale-up chemistry where strong acylating power can reduce reaction time compared with less reactive Benzoic Acid derivatives.

BENZOYL PEROXIDE PRODUCTION

Benzoyl peroxide production is the most important industrial application for Benzoyl Chloride.
The process converts benzoyl chloride functionality into the peroxide linkage under tightly controlled conditions.
Benzoyl peroxide is an energetic organic peroxide and requires its own dedicated process-safety controls.
Raw-material purity, moisture, temperature and impurity control can influence peroxide-process reliability.
Benzoyl Chloride Anhydrous is valuable because uncontrolled hydrolysis would consume feedstock and introduce Benzoic Acid and hydrogen chloride into the process.
Industrial peroxide manufacture should use dedicated engineering and hazard controls appropriate to organic peroxide chemistry.

PHARMACEUTICAL SYNTHESIS

Benzoyl Chloride is widely useful in pharmaceutical intermediate chemistry because benzoyl groups can alter reactivity, protect functional groups or remain in the final molecular structure.
N-benzoylation can reduce amine basicity and protect nitrogen during later synthetic steps.
O-benzoylation can protect alcohol or phenol functionality.
Anhydrous reagent improves stoichiometric control when water-sensitive substrates, catalysts or bases are used.
Pharmaceutical manufacture must control residual Benzoyl Chloride, Benzoic Acid, hydrogen chloride-derived salts and process-related impurities according to the validated route.

DYE AND PIGMENT SYNTHESIS

Benzoyl Chloride is an established intermediate for dyes and pigments.
Aromatic amines, phenols and other nucleophiles can be benzoylated to alter solubility, reactivity, crystallinity or colorant performance.
Benzoyl groups can also serve as temporary protecting groups during multistep colorant synthesis.
The required purity depends on downstream color sensitivity and impurity tolerance.
Low-color Benzoyl Chloride is preferred where trace discoloration would carry into the final dye or pigment.

FRAGRANCE AND PERFUME INTERMEDIATES

Benzoyl Chloride can be used to produce benzoate esters used in fragrance and perfume chemistry.
Alcohol structure determines the odor, volatility and solvent properties of the resulting benzoate ester.
Because Benzoyl Chloride is highly reactive, esterification can proceed under milder conditions than direct equilibrium esterification with Benzoic Acid.
Residual acid chloride must be removed or quenched fully before fragrance intermediates are purified.
Final fragrance suitability depends on downstream purification and regulatory status of the finished ester.

ANALYTICAL DERIVATIZATION

Benzoyl Chloride is useful in analytical chemistry because it converts many polar analytes into benzoyl derivatives.
Benzoylation can improve ultraviolet absorbance and chromatographic retention.
Phenols and biogenic amines are common derivatization targets.
The reagent is often used in controlled alkaline or buffered conditions so that nucleophilic analytes react rapidly.
Excess Benzoyl Chloride can be hydrolyzed after derivatization.
Analytical-grade procedures should control reagent blank, hydrolysis products and derivative stability.

ALCOHOL REACTIVITY

Alcohols react with Benzoyl Chloride to form benzoate esters.
A base or hydrogen-chloride scavenger is commonly used because the process generates acidic by-products.
Primary, secondary and selected tertiary-structure alcohols differ in steric reactivity.
Moisture competes directly with the desired alcohol and reduces reagent efficiency.
Anhydrous solvent and dry equipment therefore improve selectivity in high-value esterification.

PHENOL REACTIVITY

Phenols can be benzoylated to form aryl benzoate esters.
Phenoxide formation with base generally increases nucleophilicity.
The reaction is widely used in synthesis, protection and analytical derivatization.
Substituent electronics influence reaction rate.
Water can hydrolyze unreacted Benzoyl Chloride and should be controlled where stoichiometric precision is important.

AMINE REACTIVITY

Primary and secondary amines react rapidly with Benzoyl Chloride to form benzamides.
The reaction generates hydrogen chloride or an amine hydrochloride salt unless a separate base is present.
Amine excess can act as both nucleophile and acid scavenger, but this can increase raw-material consumption.
Tertiary amines are commonly used as non-nucleophilic or weakly nucleophilic acid scavengers in appropriate systems.
The reaction can be strongly exothermic and should be temperature controlled at scale.

BASE SELECTION

A base is commonly used to neutralize hydrogen chloride formed during benzoylation.
Inorganic bases can be used in biphasic Schotten-Baumann processes.
Organic tertiary amines are common in anhydrous organic synthesis.
Base selection affects salt formation, phase behavior, purification and reaction rate.
The base must also be compatible with the substrate and desired product.
Excess strong base can cause competing reactions in sensitive molecules.

SOLVENT SELECTION

Dry solvent selection is important in anhydrous Benzoyl Chloride chemistry.
The solvent should dissolve the substrate and reagent without reacting undesirably with the acid chloride.
Alcohol solvents are generally inappropriate when the goal is to preserve Benzoyl Chloride because they are themselves nucleophilic and form esters.
Water and wet solvent directly hydrolyze the reagent.
Dry hydrocarbon, ether, chlorinated or polar aprotic solvents may be used depending on the reaction route and safety requirements.
Solvent compatibility should be validated experimentally.

INERT GAS HANDLING

Dry nitrogen or another suitable inert gas can be used to reduce atmospheric moisture entry during transfer and storage.
Inert-gas blanketing is especially valuable after a container has been opened repeatedly.
Nitrogen should be dry and clean enough for the process requirement.
Inerting does not eliminate the need for ventilation because leaks can release corrosive Benzoyl Chloride vapor and hydrogen chloride.
Oxygen exclusion is generally less critical than moisture exclusion unless the downstream process has additional sensitivity.

MATERIALS OF CONSTRUCTION

Benzoyl Chloride and generated hydrogen chloride can attack unsuitable metals.
Materials of construction should be selected from current compatibility data for the exact temperature and moisture condition.
Dry Benzoyl Chloride can behave differently from partially hydrolyzed material containing acid.
Water contamination can sharply increase corrosivity because hydrochloric acid is generated.
Gaskets, seals, hoses and pump materials should also be evaluated for acid chloride compatibility.
Glass-lined, suitable stainless-steel or specialty corrosion-resistant equipment can be considered only after application-specific compatibility review.

QUALITY CONTROL

Important Benzoyl Chloride Anhydrous quality-control parameters include identity, assay, appearance, color, density, refractive index, water content, Benzoic Acid content and residue on evaporation where specified.
High-purity commercial grades commonly use assay values around 98-99% or higher.
Density around 1.21 g/cm³ and refractive index around 1.553 provide useful secondary identity checks.
Water content is especially important for anhydrous-grade applications.
Benzoic Acid is a key hydrolysis-related impurity and can be monitored directly or indirectly through acid-related quality parameters.
The current Ataman Chemicals specification and batch COA should control formal acceptance.

ASSAY

Assay measures the concentration of Benzoyl Chloride in the commercial product.
Gas chromatography and titrimetric methods are commonly used depending on the quality specification.
An assay of 99% or higher is common in high-purity synthesis grades, while other industrial grades can use different limits.
Assay should be considered together with water, color and hydrolysis impurities.
A high nominal assay does not replace an explicit water specification when an anhydrous process requires moisture control.

WATER CONTENT

Water content is a critical specification for Benzoyl Chloride Anhydrous.
Karl Fischer methods can be adapted for acid chlorides, but method suitability must account for reagent chemistry and possible analytical interference.
The analytical method should therefore be validated for Benzoyl Chloride rather than copied blindly from a neutral solvent procedure.
The acceptance limit should be stated on the current product specification or purchase agreement.
No universal maximum water value is assigned in this authority page because commercial anhydrous requirements vary.

BENZOIC ACID IMPURITY

Benzoic Acid is the direct hydrolysis product of Benzoyl Chloride.
An increase in Benzoic Acid can indicate water exposure, storage degradation or incomplete purification.
Benzoic Acid is less reactive than Benzoyl Chloride and therefore reduces effective benzoylating capacity.
The impurity can also crystallize in colder lines or concentrated process mixtures.
Moisture exclusion is the most direct way to limit hydrolytic Benzoic Acid formation during storage.

COLOR

High-purity Benzoyl Chloride is normally colorless to pale yellow.
Darkening can indicate thermal history, contamination, metal contact or side-product formation.
Low color is important in pharmaceutical, dye, fragrance and specialty resin applications.
Color should be compared against the agreed product specification and batch COA.

REFRACTIVE INDEX

Benzoyl Chloride has a refractive index around 1.553 at 20°C in widely cited reference data.
Refractive index provides a rapid secondary identity and purity check.
Temperature must be controlled because refractive index changes with temperature.
Unexpected deviation can indicate contamination or product mix-up.

RESIDUE ON EVAPORATION

Some synthesis-grade specifications include a residue-on-evaporation limit.
Low residue indicates low concentration of nonvolatile contamination.
Metal salts, polymeric material, high-boiling by-products and corrosion products can increase residue.
This parameter can be useful in high-purity synthesis and analytical applications.

STORAGE

Benzoyl Chloride Anhydrous should be stored in tightly closed moisture-resistant containers in a cool, dry and well-ventilated area.
Dry inert-gas blanketing is recommended where the product is repeatedly transferred or where a strict anhydrous specification must be preserved.
The material should be protected from water, humid air, alcohols, amines, strong bases and incompatible reactive chemicals.
Storage below approximately 30°C is common in commercial guidance, while some grades recommend cooler dark storage.
The original package label, current SDS and product specification should control the exact approved storage range.
Partially used containers should be resealed immediately.

SHELF LIFE

Shelf life depends on package integrity, moisture exclusion, storage temperature and starting purity.
Benzoyl Chloride can remain chemically stable in a dry sealed container but hydrolyzes progressively if moisture enters.
Routine inspection should include appearance and package condition.
Long-stored material used in moisture-critical synthesis can be checked for assay, water and Benzoic Acid content before release.
The original supplier expiry or retest period should control formal shelf-life decisions.

SAFETY AND HANDLING

Benzoyl Chloride is a corrosive and toxic reactive liquid.
Current commercial hazard information commonly includes toxic or harmful effects by inhalation, swallowing and skin contact, severe skin burns and eye damage, and skin sensitization.
The vapor is lachrymatory and highly irritating to the respiratory tract.
Inhalation of significant vapor or aerosol can cause severe respiratory injury and delayed pulmonary edema.
Closed transfer, local exhaust, chemical-resistant gloves, protective clothing and full eye/face protection are important handling controls.
Respiratory protection should be selected through workplace risk assessment and the current SDS.

CURRENT EU HARMONIZED CLASSIFICATION

Current European harmonized classification identified in the active regulatory record includes Skin Corrosion Category 1B with H314 and Specific Target Organ Toxicity Single Exposure Category 3 with H335.
H314 indicates severe skin burns and eye damage.
H335 indicates possible respiratory irritation.
Commercial SDS documents can include additional self-classified acute toxicity and sensitization hazards.
The current regional SDS for the supplied grade should therefore control workplace labeling and PPE.

ACUTE TOXICITY

Commercial hazard classifications commonly identify Benzoyl Chloride as toxic or harmful by inhalation and harmful by oral or dermal exposure.
Inhalation is especially serious because the substance is a corrosive lachrymator and can damage the respiratory tract.
Mist generation should be avoided.
Work should be performed in closed systems or effective local exhaust where practical.
Emergency respiratory response should follow the current SDS.

CORROSIVITY

Benzoyl Chloride is corrosive to skin, eyes, mucous membranes and certain metals.
The hazard is intensified by hydrolysis because hydrogen chloride is generated in contact with moisture.
Chemical splash goggles plus face protection are appropriate for transfer and reaction charging.
Glove selection should be based on verified permeation compatibility rather than generic acid resistance.
Emergency shower and eyewash facilities should be available in handling areas.

SKIN SENSITIZATION

Commercial GHS classifications commonly include H317, indicating that Benzoyl Chloride may cause an allergic skin reaction.
Repeated skin contact should therefore be prevented even when no immediate burn is apparent.
Contaminated clothing should be removed and laundered or disposed of according to site procedures.
Workplace hygiene should prevent contamination of common surfaces.

FIRST AID

After inhalation, remove the affected person to fresh air without exposing rescuers and obtain immediate medical attention.
Respiratory effects can be delayed, so medical observation can be required even when the person initially appears improved.
After eye contact, rinse cautiously and continuously with clean water and obtain urgent medical attention.
After skin contact, remove contaminated clothing and rinse the affected area immediately according to the current SDS.
After ingestion, do not induce vomiting unless specifically directed by medical professionals and obtain immediate medical attention.
Current product-specific SDS instructions should take precedence in every emergency.

SPILL MANAGEMENT

Benzoyl Chloride spills should be isolated from water and humid cleanup methods until a controlled response strategy is established.
Personnel should wear suitable chemical and respiratory protection.
Prevent release to drains, surface water and soil.
Inert dry absorbent compatible with acid chlorides can be used for small spills where the SDS permits.
Large releases require specialist emergency response because hydrolysis and hydrogen chloride evolution can complicate cleanup.
Collected waste should be transferred to suitable corrosion-resistant labeled containers and managed according to local hazardous-waste requirements.

FIRE RESPONSE

Benzoyl Chloride is a combustible reactive liquid.
Water can react with Benzoyl Chloride and generate corrosive hydrogen chloride, so firefighting strategy must follow the current SDS rather than generic liquid-fire assumptions.
Suitable extinguishing media can include dry chemical, carbon dioxide or compatible foam depending on the surrounding fire and SDS instructions.
Thermal decomposition can generate hydrogen chloride, carbon monoxide, carbon dioxide and irritating fumes.
Firefighters should use self-contained breathing apparatus and protective clothing.
Containers exposed to fire should be cooled using methods consistent with the product's water-reactivity precautions and emergency plan.

TRANSPORT

Benzoyl Chloride is transported under UN 1736.
Widely used transport classification assigns Class 8 and Packing Group II.
The proper shipping name is Benzoyl Chloride.
Transport packages should remain dry, tightly closed and compatible with corrosive acid chloride service.
The current SDS and applicable ADR, RID, IMDG, IATA or local dangerous-goods rules should control shipment.

ENVIRONMENTAL CONSIDERATIONS

Benzoyl Chloride should not be released directly to water because it hydrolyzes and can create local acidity and Benzoic Acid loading.
The parent acid chloride is short-lived in water because hydrolysis is rapid, but that does not make uncontrolled discharge acceptable.
Hydrogen chloride generated during hydrolysis can alter local pH.
Benzoic Acid formed by hydrolysis contributes organic load to wastewater.
Current SDS information should be used to determine aquatic and disposal precautions.
Waste should be neutralized or destroyed only under a validated chemical-waste procedure.

REGULATORY CONSIDERATIONS

Benzoyl Chloride is a defined hazardous chemical intermediate rather than a direct consumer ingredient.
The substance is subject to chemical registration, transport, workplace and environmental requirements that vary by jurisdiction.
Use in pharmaceutical, food-related, cosmetic or regulated-product manufacturing does not make the raw Benzoyl Chloride suitable for direct contact with the final consumer product.
Residual reagent and hydrolysis impurities must be controlled in downstream products through validated manufacturing and purification.
Current regional SDS and regulatory documentation should be reviewed before import, storage, supply or industrial use.

COMMON FORMULATION PROBLEMS

Benzoic Acid content increases during storage
Moisture has entered the package or transfer system. Improve sealing, inert-gas handling and dry-storage controls.

Hydrogen chloride fumes appear during transfer
Benzoyl Chloride is contacting atmospheric moisture or wet equipment. Stop the source, improve containment and dry the system before resuming.

Assay is lower than expected
Hydrolysis, contamination or incomplete purification can reduce active Benzoyl Chloride content. Check water and Benzoic Acid impurity.

Water content is above specification
Hold the batch for disposition and investigate package integrity, sampling practice and storage humidity. Do not assume the material still meets anhydrous process requirements.

Reaction yield is low
Moisture can consume reagent, or substrate conversion can be limited by base, mixing, stoichiometry or phase transfer. Check water balance first.

Unexpected Benzoic Acid precipitates
Hydrolysis has occurred or the process generates Benzoic Acid during quench. Review water exposure and temperature.

Amide reaction generates excessive salt
Hydrogen chloride neutralization is consuming amine or base. Recalculate stoichiometry and select the acid scavenger intentionally.

Reaction mixture overheats
Benzoylation can be strongly exothermic. Reduce addition rate, improve cooling and review batch concentration.

Alcohol esterification is too slow
Substrate sterics, low temperature or inadequate base/catalysis may limit reaction. Verify that water has not already consumed the Benzoyl Chloride.

Phenol conversion is low
Phenol may require deprotonation or stronger reaction conditions. Check water and base equivalents.

Amine conversion is incomplete
Hydrogen chloride salt formation can deactivate the amine. Provide sufficient base or amine equivalent and improve mixing.

Product darkens during storage
Heat, metal contamination or decomposition can increase color. Review storage temperature and materials of construction.

Corrosion appears in transfer line
Moisture may be generating hydrogen chloride. Verify dryness and materials compatibility.

Container pressure increases
Reaction, heating or contamination can create vapor or gas pressure. Isolate the container and follow emergency procedures.

Solid material forms in a cold line
Benzoic Acid impurity can crystallize or Benzoyl Chloride can approach its melting point under very cold conditions. Analyze the solid before reheating.

Refractive index is outside specification
Check temperature, contamination, water and Benzoic Acid impurity.

Density is outside specification
Confirm test temperature and product identity, then investigate contamination or hydrolysis.

Residue on evaporation is high
Nonvolatile contamination, corrosion products or high-boiling impurities may be present. Hold the batch for investigation.

Karl Fischer result is inconsistent
Acid chlorides can require validated KF methodology. Confirm sample handling, reagent compatibility and method suitability.

Benzoyl Chloride is sampled in humid air
The sample can hydrolyze during sampling and produce a falsely degraded result. Use dry sampling equipment and minimize exposure.

Anhydrous grade is stored in a frequently opened drum
Repeated humid-air entry can degrade moisture quality. Use dry inert-gas blanketing or smaller containers.

Reaction uses wet solvent
Water competes directly with the intended nucleophile and generates Benzoic Acid plus HCl. Dry the solvent to the process requirement.

Reaction uses alcohol as solvent unintentionally
Alcohol reacts with Benzoyl Chloride to form benzoate ester. Select a non-nucleophilic compatible solvent.

Reaction uses aqueous base but anhydrous control is expected
Aqueous Schotten-Baumann chemistry deliberately tolerates water and should not be confused with strictly anhydrous benzoylation. Choose the process concept 
intentionally.

Strong fumes occur when opening container
Moisture exposure and vapor release can generate corrosive fumes. Open only under controlled ventilation with appropriate PPE.

Skin irritation occurs despite gloves
Glove material may have inadequate breakthrough resistance. Review permeation data for Benzoyl Chloride and replace contaminated gloves promptly.

Benzoyl peroxide process shows impurity increase
Raw-material hydrolysis or contamination may be contributing Benzoic Acid or acid load. Check Benzoyl Chloride assay and water content.

Pharmaceutical intermediate contains residual Benzoyl Chloride
Improve reaction completion, quench and purification. Residual acid chloride must be controlled through validated process specifications.

Fragrance ester has residual acid odor
Unreacted Benzoyl Chloride or HCl-related contamination may remain. Complete reaction and purification before release.

Customer asks for a universal anhydrous water limit
No universal value should be assumed. Use the exact Ataman Chemicals product specification and batch COA for the supplied grade.

Customer asks whether Benzoyl Chloride is soluble in water
The correct description is reactive with water rather than simply soluble. Hydrolysis produces Benzoic Acid and hydrogen chloride.

Customer asks for direct food or cosmetic use
Benzoyl Chloride is a reactive chemical intermediate and should not be promoted as a direct food or cosmetic ingredient.

FREQUENTLY ASKED QUESTIONS

What is Benzoyl Chloride Anhydrous?
Benzoyl Chloride Anhydrous is moisture-controlled Benzoyl Chloride used as a reactive benzoylating reagent and industrial chemical intermediate.

What is the CAS Number?
98-88-4.

What is the EC Number?
202-710-8.

What is the molecular formula?
C7H5ClO, also written C6H5COCl.

What is the molecular weight?
Approximately 140.57 g/mol.

What is the physical form?
A colorless to pale-yellow clear liquid.

What is the melting point?
Approximately -1°C.

What is the boiling point?
Approximately 197.2°C at atmospheric pressure.

What is the density?
Approximately 1.21 g/cm³ at 20°C.

What is the flash point?
Widely used safety data report approximately 72°C closed cup; the current SDS should control the formal value.

Is Benzoyl Chloride soluble in water?
It should be described as reactive with water rather than simply soluble. Water hydrolyzes it to Benzoic Acid and hydrogen chloride.

Why is the anhydrous grade important?
Moisture consumes active Benzoyl Chloride, produces Benzoic Acid and HCl, and can reduce yield or interfere with water-sensitive synthesis.

What is the maximum water content?
There is no universal anhydrous limit. Use the current product-specific specification and batch COA.

What are the main hydrolysis products?
Benzoic Acid and hydrogen chloride.

What is the main industrial use?
Production of benzoyl peroxide is the major established industrial use.

Is Benzoyl Chloride used in pharmaceuticals?
Yes. It is a common benzoylating intermediate in pharmaceutical synthesis.

Is Benzoyl Chloride used in dyes and pigments?
Yes. It is an established intermediate in dye and pigment chemistry.

Is Benzoyl Chloride used in fragrances?
Yes. It is used to prepare benzoate esters and other fragrance intermediates.

Can Benzoyl Chloride react with alcohols?
Yes. It forms benzoate esters.

Can Benzoyl Chloride react with phenols?
Yes. Phenols can be benzoylated to form aryl benzoate esters.

Can Benzoyl Chloride react with amines?
Yes. Primary and secondary amines form benzamides.

What is benzoylation?
Benzoylation is introduction of the benzoyl group, commonly using Benzoyl Chloride as the acylating reagent.

What is the Schotten-Baumann reaction?
It is a classic acylation method using an acid chloride such as Benzoyl Chloride with base to neutralize the generated acid.

Should Benzoyl Chloride be stored under inert gas?
Dry inert-gas blanketing is recommended where strict moisture control or repeated transfer makes atmospheric humidity a concern.

Can ordinary wet equipment be used?
No. Wet equipment can hydrolyze the reagent and generate corrosive hydrogen chloride.

Is Benzoyl Chloride corrosive?
Yes. Current hazard classification includes severe skin burns and eye damage, and hydrolysis generates corrosive HCl.

Is Benzoyl Chloride toxic by inhalation?
Commercial safety classifications commonly identify significant acute inhalation toxicity and serious respiratory hazard.

What is the transport UN number?
UN 1736.

What is the transport class?
Class 8, Packing Group II under widely used dangerous-goods classification.

How should Benzoyl Chloride Anhydrous be stored?
Store it dry, tightly closed, cool and well ventilated, protected from moisture, reactive nucleophiles and incompatible chemicals.

What documents should be checked before use?
Use the current Ataman Chemicals TDS, SDS and batch-specific COA together with the exact process water-content requirement.

FINAL TECHNICAL SUMMARY

Benzoyl Chloride Anhydrous is a moisture-controlled aromatic acyl chloride with CAS Number 98-88-4, EC Number 202-710-8, molecular formula C7H5ClO and molecular weight approximately 140.57 g/mol.
The product is normally a colorless to pale-yellow clear, fuming liquid with pungent lachrymatory odor.
Key reference physical properties include melting point around -1°C, boiling point around 197.2°C, density around 1.21 g/cm³ at 20°C and closed-cup flash point around 72°C.

Benzoyl Chloride is highly moisture sensitive and reacts with water to form Benzoic Acid and hydrogen chloride.
The anhydrous designation therefore refers to controlled low-moisture quality rather than a different molecular form.
No universal maximum water content is assigned because commercial anhydrous requirements vary by process and product grade.
The current product specification and batch COA should control the water-content acceptance limit.
The major industrial use is manufacture of benzoyl peroxide.
Other important applications include pharmaceuticals, dyes, pigments, fragrances, benzoate esters, surfactants, agrochemical intermediates, specialty resins, analytical derivatization and general benzoylation chemistry.
Benzoyl Chloride reacts readily with alcohols, phenols and amines to produce benzoate esters and benzamides.

Dry solvents, dry equipment and controlled inert-gas handling improve reagent efficiency in moisture-sensitive synthesis.
Water contamination reduces assay, increases Benzoic Acid impurity and generates corrosive hydrogen chloride.
Current safety information identifies Benzoyl Chloride as corrosive, acutely hazardous by inhalation and harmful by oral or dermal exposure, with additional sensitization concerns in commercial classifications.
Closed transfer, local exhaust ventilation, chemical-resistant PPE and emergency-response planning are essential.
Transport is commonly under UN 1736, Class 8, Packing Group II.
Benzoyl Chloride Anhydrous is a defined chemical substance rather than a proprietary mixture, so the molecular formula, CAS Number and molecular weight can be stated directly.

For Benzoyl Chloride Anhydrous specifications, water-content requirements, assay, packaging, TDS, SDS, COA and commercial support, contact Ataman Chemicals with the intended synthesis, purity requirement, moisture limit and packaging requirement.

Ataman Chemicals
Phone: +90 216 577 10 10
Email: info@atamankimya.com