Ethyl Acetate → 1-cyclohexyl-4H,6H-2,3,6,10b-tetraaza-benzo[e]azulen-5-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-ethoxy-1,3-dihydro-benzo[b][1,4]diazepin-2-one (Preparation 3(A) (5 g, 24.5 mmol) in glacial acetic acid (75 mL) was added cyclohexanecarboxylic acid hydrazide (Preparation 14) (3.5 g, 24.5 mmol). The reaction was heated at 120° C. for 2.5 hours, was cooled to room temperature, and EtOAc (50 mL), water (50 mL) and aqueous NaHCO3 (50 mL) were added. The mixture was stirred for 5 minutes and Et2O was added (125 mL). The suspension was stirred for 15 minutes and the solids were removed by filtration with the aid of Et2O to provide 5.92 g of 1-cyclohexyl-4H,6H-2,3,6,10b-tetraaza-benzo[e]azulen-5-one. 1H NMR (CDCl3) δ 8.36 (s, NH), 7.50 (m, 1H), 7.41 (m, 2H), 7.30 (d, 1H), 4.13 (d, 1H), 3.47 (d, 1H), 2.87 (m, 1H), 2.24 (d, 1H), 2.00 (m, 2H), 1.72-1.51 (m, 4H), 1.33 (m, 2H), 1.16 (m, 1H); MS 283.4 (M+1), 281.3 (M−1).

Provenance & Evidence