One-pot synthesis of (R)-1-(1-naphthyl)ethanol by stereoinversion using Candida parapsilosis

(R)-1-(1-Naphthyl)ethanol is an essential chiral substrate for the synthesis of nonactin and dihydro-[1H]-quinoline-2-one derivatives. Stereoinversion of (S)-1-(1-naphthyl)ethanol to (R)-1-(1-naphthyl)ethanol by whole cell biocatalysis, using Candida parapsilosis, is reported here. Candida parapsilosis possesses a requisite redox system for the stereoinversion of secondary alcohol. The reaction conditions (temperature, time, pH, organic solvent, etc.) significantly influenced the stereoinversion process. Optimum conditions were found to be the reaction temperature of 30 °C, a cellmass concentration of 200 mg/mL, pH 7 (phosphate buffer, 50 mM), a shaking speed of 200 rpm, and a 12 h reaction time. Under these optimum conditions, (R)-1-(1-naphthyl)ethanol was obtained in 100% eeR and 88% yield.