HOBt

(Hydroxybenzotriazole)

Other Names:

Benzotriazol-1-ol

N-Hydroxybenzotriazole

General Information:

Structure:

CAS Number: 2592-95-2 (anhydrous)

123333-53-9 (hydrate)

Molecular Weight: 135.13 g/mol (anhydrous)

153.14 g/mol (mono-hydrate)

Appearance: White crystalline powder

Common Uses:

Reagent for amide couplings (EDC + HOBt)

Procedure excerpt:

To a solution of the SM (1.0 g, 6.4 mmol) in DMF (5.0 mL) at 0 C was added EDC-HCl (1.2 g, 7.7 mmol), NH4Cl (1.4 g, 26.9 mmol), and HOBt (1.1 g, 8.3 mmol). The reaction . . .

[full procedure]

Safety:

Hydroxybenzotriazole (HOBt) is potentially explosive, especially in anhydrous form.

References:

1) Patent Reference: WO2014149164, page 227, (23.7 MB)

2) Wikipedia: Hydroxybenzotriazole (link)

3) www.sigmaaldrich.com: 1-Hydroxybenzotriazole hydrate (link)

2) Pearson, A. J.; Roush, W. R.; Handbook of Reagents for Organic Synthesis, Activating Agents and Protecting Groups