Triethylamine → (4S)-5,5-Diphenyl-4-(propan-2-yl)-1,3-oxazolidin-2-one

Beteiligte Stoffe

Reaktionsschritte

Trichloromethyl chloroformate (2.71 g, 13.7 mmol) was added to a mixture of (S)-2-amino-3-methyl-1,1-diphenyl-1-butanol (2) (3.18 g, 12.45 mmol) and triethylamine (2.68 g, 26.52 mmol) in CH2Cl2 at 0° C. The reaction mixture was stirred for 2 h at the same temperature and then poured into a brine solution (250 ml). The aqueous layer was made basic with NaOH pellets and organic products were extracted into AcOEt (5×200 ml). Combined organic extracts were dried over MgSO4 and concentrated under reduced pressure. The resulting crude product was washed with diethyl ether to obtain the title compound (3) (3.03 g, 86%) as a white solid. m.p. 250–251° C. (liti 250–251° C.). [α]D25=−201.59° (c, 0.0252 in DMSO). δH (DMSO-d6) 0.51 (3H, d, 3J=6.60 Hz, CH3), 0.92 (3H, d, 3J=7.20 Hz, CH3), 1.86 (1H, ds, 3J=2.10 and 6.60 Hz, CH—Me2), 4.46 (1H, d, 3J=6.5 Hz, CH—NH2), 7.24–7.72 (10H, m, Ar—H), 8.14 (1H, s, NH). δC 15.2 and 20.9 (CH3), 29.8 (CH), 64.9 (CH—NHCO), 88.4 (C—O), 125.8, 126.2, 127.9, 128.4, 128.8 and 129.1 (Ar), 140.5 and 146.1 (α-Ar), 158.1 (C═O). Ir 3295 (NH2), 1765 and 1745 (C═O). m/e (CI—NH3) 282 (MH+, 25%), 299 (MNH4+, 8%), 238 (96%), 223 (100%), 72 (100%).

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