Tetrahydrofuran → HCID 86745580, compound

Participants

Reaction Steps

N-(Diphenylmethyl)methanesulfonamide (6.34 g., 19.5 mmole, 2.5 eq.) and lithium chloride (1.65 g., 39 mmole, 5 eq.) were partially dissolved in distilled tetrahydrofuran (78 ml., 0.25M) and cooled to -40° . n-Butyllithium (2.5M in hexane, 15.6 ml., 39 mmole, 5 eq.) was added slowly. The mixture was stirred at -40° for 30 minutes and then warmed to 0° for 30 minutes. After recooling to -40° , (4S-trans)-4-(cyclohexylmethyl)-5-[[(methoxy)methylamino]carbonyl]-2,2-dimethyl-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester [3.0 g., 7.8 mmole, 1 eq., prepared as described in Example 1(b)] was added. The reaction was stirred at -40° for 30 minutes and at 0° for 30 minutes, then quenched with 1N HCl (50 ml.). The product was extracted into ether (3×75 ml.), dried (Na2SO 4 and MgSO4), and freed of solvent in vacuo. The product was purified by chromatography on silica gel (270 g. Merck) eluting with ether:hexane (1:3) followed by (1:2) to give 4.45 g. of (4S-trans)-5-[[[(diphenylmethyl)sulfonyl]-amino]acetyl]-4-(cyclohexylmethyl)-2,2-dimethyl-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester; [α]D =+30.3° (c=1.0, methanol). TLC (silica gel; ether:hexane, 1:1) Rf =0.56.

Provenance & Evidence