n-butyllithium in tetrahydrofuran; hexane 1.) -78 deg C, 30 min, 2.) -78 deg C, 30 min;

1: 4-methylpentanoic acid With pivaloyl chloride; triethylamine in tetrahydrofuran T=0°C; 1 h; 2: (R)-4-(phenylmethyl)-2-oxazolidinone With lithium chloride in tetrahydrofuran T=20°C; 38 h;

1: triethylamine; pivaloyl chloride / tetrahydrofuran / 1 h / -20 °C 2: lithium chloride / tetrahydrofuran / 3 h / -20 - 0 °C View Scheme

1: 1.) TiCl4, (i-Pr)2NEt / 1.) CH2Cl2, 0 deg C, 1 h, 2.) CH2Cl2, 0 deg C, 6 h 2: H2O2, H2O, LiOH / tetrahydrofuran / 1 h / 0 °C 3: H2 / 10percent Pd/C / methanol 4: NaOH, H2O, EDCI / tetrahydrofuran / Ambient temperature 5: DEAD, Ph3P / tetrahydrofuran / Ambient temperature 6: 100 percent / LiOH, H2O / tetrahydrofuran; methanol / 0 °C 7: H2 / 10percent Pd/C / methanol View Scheme