(R)-(+)-4-Methyl-3-pentenyl p-tolyl sulfoxide (6) was prepared from 5-chloro-2-pentanone (2) in a four-step sequence produced. Asymmestric addition of 6 with acetaldehyde at -10℃ gave optically active alcohol 7 in 85% yield, then (+)-sucatol was synthesized by in 84% yield by reductive desulfurization of 7 with Raney-Ni. The enantiomeric excesse of the target compound 1 is 45% e. e.

Key words: INFRARED SPECTROPHOTOMETRY, PROTON MAGNETIC RESONANCE SPECTROMETRY, PENTANONE, SEX PHEROMONE, DESULFURIZATION, SULFOXIDE P, REDUCTION REACTION