Trifluoroacetic acid → Tetrahydro-1,4-benzodiazepin-2-one

Participants

Reaction Steps

To a solution of 2-oxo-1,2,3,5-tetrahydro-benzo[e][1,4]diazepine-4-carboxylic acid tert-butyl ester (300 mg, 1.14 mmol) in dry DCM (10 mL) was added trifluoroacetic acid (3.42 mL, 3 mL/mmol. The reaction mixture was stirred at r.t. for 2 h. After completion of the reaction as confirmed by TLC, excess of trifluoroacetic acid and DCM were removed under vacuo to afford trifluoroacetic acid salt of 1,3,4,5-tetrahydro-benzo[e][1,4]diazepin-2-one (295 mg, 93%) as a gummy solid. The crude compound was used as such without further purification for the next step.

Provenance & Evidence