Hydrazine hydrate (1:1) → 1,5-Dihydro-3-pentafluoroethyl-[1,2]diazepino[4,5,6-cd]-indol-6-one

Participants

Reaction Steps

In a manner similar to that described for Compound 28, a solution of methyl indole-4-carboxylate (351 mg, 2.01 mmol) in dichloroethane (7 mL) was treated with pentafluoropropionyl chloride (2.51 mmol) and aluminum chloride (575 mg). The intermediate ketone (50 mg, 0.16 mmol) in MeOH (2 mL) and conc. HCl (0.02 mL) was treated, as described, with hydrazine hydrate (0.1 mL). The reaction was quenched at 0° C. with 1 M NaOAc and the aqueous layer was adjusted to pH=8 with 1 M NaOH. The product was isolated by extraction with CH2Cl2, and recrystallized (CH2Cl2/MeOH/hexanes) to give 1,5-dihydro-3-pentafluoroethyl-[1,2]diazepino[4,5,6-cd]-indol-6-one, 15 mg (28%) as a yellow solid: 1H NMR (300 MHz, d6-DMSO) δ 7.16 (app br t, 1H), 7.54 (m, 2H), 7.65 (m, 1H), 10.87 (s, 1H), 12.15 (s, 1H). HRMS (FAB, Mna+) Calcd for C11H10N3Ona: 352.0674. Found: 352.0668.

Provenance & Evidence