Triethylamine → (4S)-4-Methyl-5,5-diphenyl-1,3-oxazolidin-2-one

Participants

Reaction Steps

Trichloromethyl chloroformate (6.37 g, 32.19 mmol) was added to a mixture of (S)-2-amino-1,1-diphenyl-1-propanol (10) (6.65 g, 29.26 mmol) and triethylamine (6.31 g, 62.3 mmol) in CH2Cl2 at 0° C. The reaction mixture was stirred for 5 h at the same temperature, poured into a brine solution (150 ml), and diluted with more dichloromethane. After collecting insoluble impurities through the Buchner funnel, the organic layer was separated and the aqueous layer was washed once with a mixture of dichloromethane and AcOEt. The combined organic extracts were dried over MgSO4/K2CO3 and concentrated under reduced pressure. The resulting crude product was washed with diethyl ether, water, AcOEt and diethyl ether again, to obtain the title compound (11) (5.67 g, 76%) as a white solid. m.p. 264–266° C. [α]D25=−279.71° (c, 0.0414 in DMSO). δH 0.82 (3H, d, 3J=6.30 Hz, CH3), 4.65 (1H, q, 3J=6.0 Hz, CH—NH2), 7.10–7.70 (10H, m, Ar—H), 7.93 (1H, broad s, NH). δC 19.6 (CH3), 55.9 (CH—NH2), 85.6 (C—O), 126.3, 126.4, 128.1, 128.6, 128.8 and 129.1 (o-, m- and p-Ar), 140.6 and 144.2 (α-Ar), 157.6 (C═O). ir 3254 (NH), 1745 and 1725 (C═O). m/e (CI—NH3) 254 (MH+, 9%), 271 (MNH4+, 55%), 52 (100%).

Provenance & Evidence