N,N,N',N'-Tetramethylazodicarboxamide → (3S)-3-Methyl-8-(phenylsulfonyl)-1,3,4,8-tetrahydro-2H-[1,4]oxazepino [6,7-e]indole

Participants

Reaction Conditions

Reaction Steps

1,1′-Azobis(N,N-dimethylformamide) (57 mg, 0.33 mmol) was added to a solution of 5-hydroxy-1-(phenylsulfonyl)-1H-indole-4-carbaldehyde (Intermediate 10, 0.050 g, 0.16 mmol), S-(−)-2-(tert-butoxycarbonylamino)-1-propanol (58 mg, 0.33 mmol) and triphenylphosphine (87 mg, 0.33 mmol) in DCM (5 mL). The mixture was stirred at 45° C. for 2 days and the mixture was evaporated. The crude material was purified by flash chromatography using 1% to 2.5% MeOH in DCM. This boc-protected intermediate was dissolved in DCM (3 mL) and TFA (1 mL) was added. The mixture was stirred for 1 hour and evaporated. The residue was dissolved in THF (3 mL) and sodium triacetoxyborohydride (30.0 mg, 0.141 mmol) was added all in one portion. The reaction mixture was stirred for 20 minutes and evaporated. The crude product was purified by flash chromatography on silica gel using MeOH:DCM:NEt3 (5:94:1) as the eluent to give a light yellow solid (15 mg) of the title compound. MS m/z 343 [M+H]+.

Provenance & Evidence