Acetohydrazide → 8-Bromo-1-methyl-5,6-dihydrospiro[benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepine-4,1'-cyclopropane]
Reaction equation
[Br:1][C:2]1[CH:15]=[CH:14][C:5]2[NH:6][C:7](=S)[C:8]3([CH2:11][NH:12][C:4]=2[CH:3]=1)[CH2:10][CH2:9]3.[C:16]([NH:19][NH2:20])(=O)[CH3:17]>C(O)CCC>[Br:1][C:2]1[CH:15]=[CH:14][C:5]2[N:6]3[C:16]([CH3:17])=[N:19][N:20]=[C:7]3[C:8]3([CH2:10][CH2:9]3)[CH2:11][NH:12][C:4]=2[CH:3]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 7-bromo-4,5-dihydrospiro[benzo[b][1,4]diazepine-3,1′-cyclopropane]-2(1H)-thione (500 mg, 1.77 mmol) and acetohydrazide (1.05 g, 14.2 mmol) in n-butanol (15 mL) was heated to 130° C., and maintained at the same temperature for 12 hours. The reaction mixture was concentrated, extracted with ethyl acetate (15 mL), washed with water (25 mL*2). The organic phase was separated, dried by sodium sulfate, filtered and concentrated to give the crude product, which was purified by column chromatography (silica gel, dichloromethane/methanol=30:1) to afford 8-bromo-1-methyl-5,6-dihydrospiro[benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepine-4,1′-cyclopropane] (286 mg, 53%). 1H NMR (300 MHz, d6-DMSO): δ 7.31-7.28 (m, 2H), 7.11 (dd, J=6.0 Hz, J=2.4 Hz, 1H), 5.80-5.78 (m, 1H), 3.36-3.35 (m, 2H), 2.37 (s, 3H), 0.88-0.86 (m, 2H), 0.77-0.73 (m, 2H). LRMS (M+H)+: calcd 304.03. found 304.