2-chloroacetyl bromide

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of sodium bicarbonate (15 mmol) in water (5 mL) and DCM (30 mL) at 0° C. is added chloroacetyl bromide (12 mmol), followed by immediate addition of 1-cyclobutylpiperazine (10 mmol). The mixture is stirred at 0° C. for an additional 40 min. To the mixture is added aqueous sodium bicarbonate (15 mL) and DCM (30 mL). The layers are separated and the organic layer is dried (MgSO4) and solvent is removed in vacuo to give 2-chloro-1-(4-cyclobutyl-piperazin-1-yl)-ethanone, which is used in the next step without further purification. 1H NMR (300 MHz, CDCl3) δ 4.07 (2H, s), 3.64 (2H, t), 3.52 (2H, t), 2.74 (1H, m), 2.36 (2H, t), 2.31 (2H, t), 1.72-2.08 (6H, m); MS (+VE) m/z 217.1 (M++1). The layers are separated the organic layer is dried (MgSO4) and solvent is removed in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In the manner given in Example 1, 7-chloro-5-(o-chlorophenyl)-3H-1,4-benzodiazepin-2-yl hydrazine was reacted with chloroacetyl bromide and after 1.5 hours with sodium acetate, then the mixture was refluxed to give 8-chloro-1-(chloromethyl)-6-(o-chlorophenyl)-4H-s-triazolo[4,3-a][1,4]benzodiazepine. the mixture was refluxed