Hydrochloric Acid → 5-[2-[(Butylamino)carbonyl]-3-methyl-1-butenyl]-4-(cyclohexylmethyl)-2,2-dimethyl-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester

Participants

Reaction Conditions

Reaction Steps

The procedure of Poss, M. A. and Reid, J. A. (Tet. Lett. 1992, 33 (11), 1411-14) was used. A 2.0M solution of trimethylaluminum (1.25 mL, 2.5 mmol) in hexane was added to a 1,2-dichloroethane (1.25 mL) solution containing butylamine (0.25 mL, 2.5 mmol) at r.t. and stirred for one h. A 1,2-dichloroethane (1.25 mL) solution containing 5-[2-[(ethoxy)carbonyl]-3-methyl-1-butenyl]-4-(cyclohexylmethyl)-2,2-dimethyl-3-oxazolidinecarboxylic acid, 1,1-dimethylethyl ester (424 mg, 1.0 mmol) was added to the reactants prepared above and heated at 70° C. for 16 h. The reaction was cooled to 0° C., diluted with CHCl3, and treated with 1N HCl. The organic phase was separated and the aqueous phase extracted with CHCl3 (2×). The combined organic extracts were dried (Na2SO4), filtered through MgSO4 and concentrated in vacuo. Silica gel chromatography (5:1 hexane:Et2O) of the concentrate afforded the title compound (408 mg, 88%). MS (ESI) m/e 463 (M-H)-.

Provenance & Evidence