PRODUCTS

HYDROXYBENZOTRIAZOLE

Hydroxybenzotriazole (abbreviated HOBt) is an organic compound that is a derivative of benzotriazole.
Hydroxybenzotriazole is a white crystalline powder, which as a commercial product contains some water (~11.7% wt as the HOBt monohydrate crystal).
Anhydrous Hydroxybenzotriazole is explosive.

Hydroxybenzotriazole is mainly used to suppress the racemization of single-enantiomer chiral molecules and to improve the efficiency of peptide synthesis.

CAS: 2592-95-2
European Community (EC) Number: 219-989-7

IUPAC Name: 1-hydroxybenzotriazole
Molecular Formula: C6H5N3O
Molecular Weight: 135.12 g/mol

Solubility: 8.4 [ug/mL] (The mean of the results at pH 7.4)

1-Hydroxybenzotriazole, 2592-95-2, HOBt, 1H-Benzo[d][1,2,3]triazol-1-ol, N-Hydroxybenzotriazole, 1H-Benzotriazole, 1-hydroxy-, Benzazimidol, 1H-Benzotriazol-1-ol, 1H-1,2,3-Benzotriazol-1-ol, 1-Hydroxy-1H-benzotriazole, 1-Benzotriazolol, benzotriazol-1-ol, 1-HYDROXY-BENZOTRIAZOLE, 1-hydroxybenztriazole, 1-Hydroxybenzotrizole, N-Hydroxybenzotriazole hydrate, 1-Hydroxy-1H-benzotriazole hydrate, A2T929DMG4, DTXSID3044627, 1-Hydroxy-1,2,3-benzotriazole, Benzazimidol hydrate, N-Hydroxybenzotriazol, 1-hydroxybenzotriazol, CCRIS 2605, 1-hydroxy benzotriazole, 1H-BENZOTRIAZOLE, HYDROXY-, EINECS 219-989-7, 1-Hydroxy-1H-benzotriazol, BRN 0004515, 1-hydroxyl-1H-benzotriazole, UNII-A2T929DMG4, 1,2,3-Benzotriazol-1-ol, HOBt,Anhydrous, benztriazol-1-ol, 1-hydroxybenztriazol, 1-HYDROXY-1-H-BENZOTRIAZOLE, N-hydoxybenzotriazole, N-hydroxybenztriazole, N-Hydroxybezotriazole, 1-hydoxybenzotriazole, 1-hydroxibenzotriazol, 1-hydroxybenzothazole, 1-hydroxybezotriazole, 1-hyroxybenzotriazole, benzotriazole n-oxide, HOBO, l-hydroxybenzotriazole, 1hydroxy-benzotriazole, 3-hydroxybenzotriazole, N-hydroxy-benzotriazol, 1-hydroxy benzotriazol, 1-hydroxy benztriazole, 1-hydroxy-benztriazole, 1-hydroxy-bezotriazole, 1-hydroxybenztria zole, 1-hydroxylbenzotriazole, 1H-Benzotriazole, 1-hydroxy-, hydrate, N-hydroxy benzotriazole,N-hydroxy-benzotriazole,1 -hydroxybenzotriazole,1- hydroxybenzotriazole,1-hydroxybenzo-triazole,1-hydroxybenzotri-azole, 1H-benzotriazole-1-ol, N-hydroxyl-benzotriazole, 1-N-Hydroxybenzotriazole, 1-hydroxy-benzo-triazole, SCHEMBL184, 1-hydroxy-1H-benztriazole, hydroxybenzotriazole (HOBt), ML001006716, 1-hydroxy-(1H)-benzotriazole, SCHEMBL2845655, SCHEMBL3295216, SCHEMBL3672275, CHEMBL1389920, DTXCID1024627, CHEBI:176967, 1-H-1,2,3-benzotriazol-1-ol, 1-hydroxy-benzo-1,2,3-triazole, HMS1724G04, HMS2742F11, CS-B0704, MFCD0006569, Tox21_302480, 1-hydroxy-1H-1,2,3-benzotriazole, NSC778225, 1H-benzo[d][1,2,3]triazole-1-ol, AKOS000120715, AC-2558, AM84845, NSC-778225, CIS-7-OCTADECENOICACIDMETHYLESTER, 1-HYDROXY-1H-BENZOTRIAZOLE[MI], NCGC00246157-01, NCGC00256701-01, BP-12840, SMR000349651, CAS-2592-95-2, H0468, NS00007863, EN300-17272, A818093, AB-131/40192094, Q161641, J-504791, 1-HYDROXYBENZOTRIAZOLE (WET WITH 14% WATER), 1H-1,2,3-Benzotriazol-1-ol (wet with 14% water), Z56900935, 1-Hydroxybenzotriazole (hobt) (wetted with ~20% water), F0001-2469, 1-Hydroxybenzotriazole;N-Hydroxybenzotriazole; 1-Hydroxy-1H-benzotriazole; 1-Hydroxybenzotriazole anhydrous

Hydroxybenzotriazole has become an everyday reagent in many chemistry labs, and the number of reports of its application in organic synthesis is boosted to hundreds per year.
Combined with a dehydrating agent and a tertiary amine, Hydroxybenzotriazole is an excellent auxiliary in preparation of amides.

Some of the dehydrating agents used in the process are also derivatives of Hydroxybenzotriazole.
In some instances, these derivatives, HBTU, TBTU and BOP are used alone without addition of Hydroxybenzotriazole.
Combinations of Hydroxybenzotriazole with dehydrating agents, especially DIC, HBTU and BOP are common reagents in solid-phase synthesis of peptides.
Use of Hydroxybenzotriazole together with DCC, EDC or HBTU in preparation of carboxylic esters is also relatively common.
Hydroxybenzotriazole can likewise promote formation of C–C bonds in coupling of carboxylic acids with cyanoacetates and acetoacetates.
In the presence of HBTU, aminoacids react with diazomethane to give their higher homologs.

Hydroxybenzotriazole is a coupling reagent used to synthesize amides by the condensation reaction between the activated ester/acid and the amino group of protected amino acids.
Hydroxybenzotriazole is also used as a racemization suppressor during peptide synthesis.

Use in peptide synthesis:

Automated peptide synthesis involves the condensation of the amino group of protected amino acids with the activated ester.
Hydroxybenzotriazole is used to produce such activated esters.
These esters are insoluble (like the N-hydroxysuccinimide esters) and react with amines at ambient temperature to give amides.

Hydroxybenzotriazole is also used for the synthesis of amides from carboxylic acids aside from amino acids.
These substrates may not be convertible to the acyl chlorides.
For instance amide derivatives of ionophoric antibiotics have been prepared in this way.

Applications:

• Hydroxybenzotriazole hydrate can be used as a condensation reagent to prepare:
Poly-γ-glutamic acid methyl ester from a dimer of γ-glutamic acid.
• Oxadiazoles via cyclo condensation of amidoximes with trifluoroacetic anhydride or benzoic acid derivatives.

For many years, Hydroxybenzotriazole (HOBt) has been used as a coupling reagent in peptide synthesis, especially in combination with dicyclohexylcarbodiimide (DCC).
Later, other benzotriazole derivates such as 6-chloro-1-hydroxybenzotriazole (6-Cl-HOBt) and 1-hydroxy7-azabenzotriazole (HOAt) have been introduced.
During the last decade, phosphonium and aminium/uronium salts of hydroxybenzotriazoles have been suggested for the synthesis of peptides.

Hydroxybenzotriazole is mainly used to suppress the racemization of single-enantiomer chiral molecules and to improve the efficiency of peptide synthesis.

Hydroxybenzotriazole hydrate can be used as a condensation reagent to prepare:
Poly-γ-glutamic acid methyl ester from a dimer of γ-glutamic acid.
Oxadiazoles via cyclo condensation of amidoximes with trifluoroacetic anhydride or benzoic acid derivatives.