Diazomethane → 2-Methyl-1,2,3-benzotriazole

Participants

Reaction Steps

Benzotriazole free base (from above; 155 mg, 0.36 mmol) in CH2Cl2 (2.5 mL) was treated while stirring with etheral diazomethane (2-10 eq.). After about 2 h (10-20° C.) the solvent and excess diazomethane were removed in vacuo and the residue was chromatographed on silica (Chromatotron; 1% conc. NH4OH; 1.5% MeOH, 97.5% (CHCl3)) to afford (36%; 57 mg) 2-N-methyl benzotriazole derivative (Example 169) and (15%; 24 mg) 3-N-methyl benzotriazole (Example 168).

Provenance & Evidence