(S)-(-)-4-ISOPROPYL-5,5-DIPHENYL-2-OXAZOLIDINONE

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of (S)-4-isopropyl-5,5-diphenyl-2-oxazolidinone (3) (2.9 g, 10.31 mmol) in MeOH/AcOH and a 10% Pd (435 mg, 4.09 mmol) on activated carbon was shaken for 68 h under 4–5 atm pressure of hydrogen at room temperature. The catalyst was filtered off over Hyflo Super Cell and organic solvents were evaporated under reduced pressure. The resulting residue was treated with HCl (2.0 M, 50 ml), stirred for 2 h at room temperature, made basic with NaOH pellets, and saturated with K2CO3 and NaCl. Organic compounds were then extracted into AcOEt (3×100 ml), dried over MgSO4/K2CO3 and concentrated under reduced pressure to obtain a crude product. Re-crystallisation from petroleum ether gave the title compound (4) (1.79 g, 72%) as a light-brown solid. m.p. 71–72° C. [α]D25=−4.19° (c, 0.1097 in CHCl3). δH 0.78 (3H, d, 3J=6.60 Hz, CH3), 0.91 (3H, d, 3J=7.20 Hz, CH3), 1.26 (2H, broad s, NH2), 1.62 (1H, ds, CHMe2), 3.45 (1H, dd, 3J=10.5 and 2.40 Hz, CH—NH2), 3.70 (1H, d, 3J=10.5 Hz, CH—Ph2), 7.00–7.40 (10H, m, Ar—H). δC 14.2 and 21.5 (CH3), 28.9 (CH—Me2), 58.1 and 58.9 (CH—NH2 and CH—Ph2), 126.5, 126.7, 128.2, 128.5, 128.8 and 129.0 (o-, m- and p-Ar), 143.5 (2×α-Ar). Anal. Calcld for C17H21N: C 85.30; H 8.84; N 5.85. Found: C 85.12; H 8.91; N 5.96. ir 3361 (NH2). m/e (CI—CH4) 240 (MH+, 8%), 72 (100%). The catalyst was filtered off over Hyflo Super Cell and organic solvents were evaporated under reduced pressure The resulting residue was treated with HCl (2.0 M, 50 ml) Organic compounds were then extracted into AcOEt (3×100 ml) dried over MgSO4/K2CO3 concentrated under reduced pressure to obtain a crude product

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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%). were extracted into AcOEt (5×200 ml) Combined organic extracts were dried over MgSO4 concentrated under reduced pressure The resulting crude product was washed with diethyl ether