(4S)-4-propan-2-yl-1,3-oxazolidin-2-one

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cooled solution (-78° C.) of 1.5910 g (12.316 mmole of (+)-(4S)-3-(1-oxopropyl)-4-(1-methylethyl)-2-oxoazolidinone (A) in 20 ml of THF under N2 atmosphere is added 5.80 ml of 2.32M n-BuLi in hexane (13.55 mmole, 1.1 equiv.) to form the conjugate base. The milky slurry is stirred for 1 hour before 1.11 ml (1.1852 g, 12.81 mmoles, 1.04 equiv., mwt 92.53, bp 77°-9° C., d 1.065) of propionyl chloride is added in one portion. The slurry dissolves instantly to a clear orange solution. After stirring an additional 15 min. at -78° C., the reaction is quenched with 20 ml sat. NH4Cl, and the THF is removed in vacuo at RT (room temp). The resultant concentrate is taken up in ether and extracted successively with aq. NaHCO3, water, brine and dried over anh. Na2SO4. Evaporation of the solvent followed by flash chromatography affords 1.82 g (80%) of purified product B as a viscous yellow oil. Proton NMR (200 MHz) in CDCl3 shows: ##STR58## 4.41 (d of t, 1H, J=7.6 Hz, J=3.6 Hz, C3 -H); 4.22 (m, 2H, 2J=5.4 Hz, C4 -H); 2.92 (q of d, 2H, J=7.7 Hz, J=4.0 Hz, C9 -H); 2.35 (m, 1H, J=7.0 Hz, J=3.9 Hz, C2 -H); 1.14 (t, 3H, J=7.7 Hz, C10 -H); 0.89, 0.85 (d, 6H, J=7.0 Hz, C1 -H). to form the conjugate base is added in one portion The slurry dissolves instantly to a clear orange solution the reaction is quenched with 20 ml sat. NH4Cl the THF is removed in vacuo at RT (room temp) The resultant concentrate extracted successively with aq. NaHCO3, water, brine dried over anh. Na2SO4 Evaporation of the solvent

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mechanically stirred, cooled (-78° C.) solution of the oxazolidinone of Step 5 (32.3 g, 250 mmol) in anhydrous THF (830 mL) was metalated with 163 mL (1.6M in hexane, 261 mmol) of n-BuLi and treated with freshly distilled butanoyl chloride (28.1 mL, 271 mmol). The reaction mixture was warmed to 0° C. and stirred for 0.5 h. Excess acid chloride was hydrolyzed by the addition of 1M aqueous K2CO3 (165 mL) followed by stirring the resultant two-phase mixture for 1 h at r.t. Volatiles were removed in vacuo and the product was extracted into CH2Cl2 (3×). The combined organic extracts were successively washed with H2O and brine, dried over MgSO4 and concentrated to give the title compound as a pale yellow oil (52.1 g, quantative). A portion of this crude product was purified by flash chromatography on silica with EtOAc:hexane 1:4 to give a colorless liquid. stirred for 0.5 h Volatiles were removed in vacuo the product was extracted into CH2Cl2 (3×) The combined organic extracts were successively washed with H2O and brine dried over MgSO4 concentrated

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

Procedure: The title compound was prepared according to Evans, Mathre and Scott (J. Org. Chem., 50, 1830 (1985)) from (S)-(+)-2-amino-3-methyl-1-butanol and diethyl carbonate in the presence of K2CO3.

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mechanically stirred, cooled (-78° C.) solution of the oxazolidinone of Step 5 (32.3 g, 250 mmol) in anhydrous THF (830 mL) was metalated with 163 mL (1.6M in hexane, 261 mmol) of n-BuLi and treated with freshly distilled butanoyl chloride (28.1 mL, 271 mmol). The reaction mixture was warmed to 0° C. and stirred for 0.5 h. Excess acid chloride was hydrolyzed by the addition of 1M aqueous K2CO3 (165 mL) followed by stirring the resultant two-phase mixture for 1 h at r.t. Volatiles were removed in vacuo and the product was extracted into CH2Cl2 (3x). The combined organic extracts were successively washed with H2O and brine, dried over MgSO4 and concentrated to give the title compound as a pale yellow oil (52.1 g, quantative). A portion of this crude product was purified by flash chromatography on silica with EtOAc:hexane 1:4 to give a colorless liquid. stirred for 0.5 h Volatiles were removed in vacuo the product was extracted into CH2Cl2 (3x) The combined organic extracts were successively washed with H2O and brine dried over MgSO4 concentrated

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

Procedure: The title compound was prepared according to Evans, Mathre and Scott (J. Org. Chem., 50, 1830 (1985)) from (S)-(+)-2-amino-3-methyl-1-butanol and diethyl carbonate in the presence of K2CO3.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (6.88 g) and 4-phenylbutyryl chloride (6.88 g), the desired compound (10.23 g) was obtained as a colorless oil.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (6.88 g) and 4-phenylbutyryl chloride (6.88 g), the desired compound (10.23 g) was obtained as a colorless oil.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (5.39 g) and dodecanoyl chloride (9.46 g), the desired compound (11.3 g) was obtained as a colorless oil.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (5.39 g) and dodecanoyl chloride (9.46 g), the desired compound (11.3 g) was obtained as a colorless oil.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (4.99 g) and nonanoyl chloride (7.16 g), the desired compound (10.12 g) was obtained.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (4.99 g) and nonanoyl chloride (7.16 g), the desired compound (10.12 g) was obtained.

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

Procedure: Following the procedure described in Referential Example 3, but using 4-(S)-isopropyl-2-oxazolidinone (5.06 g) and octanoyl chloride (6.67 g), the desired compound (9.39 g) was obtained.