HCID 4447312, compound → HCID 22842919, compound

Participants

Reaction Steps

n-Butyllithium (4.48 ml., 11.2 mmole, 2.8 eq., 2.5M in hexane) was added to a solution of N-butylmethanesulfonamide [846 mg., 5.6 mmole, 1.4 eq., prepared as described in Example 1(a)] in tetrahydrofuran (16 ml., 0.35M) at -40° and stirred for 10 minutes. The reaction was then warmed to 0°, stirred for 30 minutes and cooled to -40°. (4S-trans)-4-(Cyclohexylmethyl)-2,2-dimethyl-5-(1-oxopentyl)-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester (1.5 g., 3.93 mmole, 1 eq.) in tetrahydrofuran (4 ml., 1.0M) was then added. After 90 minutes at -40°, the reaction was quenched with aqueous saturated NH4Cl, warmed to room temperature and extracted three times with ether. The organic extracts were dried (Na2SO4), filtered through MgSO4, and concentrated. The residue was chromatographed on silica gel (Merck, 80 g.) eluting with hexane:acetone (10:1) to provide 237 mg. of (4S-trans)-5-[2-[butylamino)sulfonyl]-1-butyl-1-hydroxyethyl]-4-(cyclohexylmethyl)-2,2-dimethyl-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester, isomer A; [α]D =+4.2° (c=1.0, methanol) and 101 mg. of isomer B; m.p. 138°-140°; [α]D =+5.5° (c=1.0, methanol) and 1.518 g. of a mixture of isomer A and isomer B.

Provenance & Evidence