Ammonium Chloride → tert-Butyl[(2S)-1-(1,2-oxazinan-2-yl)-1-oxo-3-phenylpropan-2-yl]carbamate

Participants

Reaction Steps

500 mg (1.9 mmol) of N-(tert-butoxycarbonyl)-L-phenylalanine were dissolved in 10 ml of DMF, and 466 mg (3.8 mmol) of 1,2-oxazinane hydrochloride (Starting Material 5), 433 mg (2.3 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 382 mg (2.8 mmol) of 1-hydroxy-1H-benzotriazole hydrate and 731 mg (5.7 mmol) of N,N-diisopropylethylamine were added in succession. The mixture was stirred at RT overnight. The reaction was then poured into a mixture of semisaturated aqueous ammonium chloride solution and ethyl acetate. The organic phase was separated off, washed successively with saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over magnesium sulphate, filtered and concentrated. This gave 620 mg (98% of theory) of the title compound.

Provenance & Evidence