Reduction of β-Ketoalkyl 2-(1-Dimethylaminoethyl)phenyl Sulfoxides : Synthesis of (-)-Matsutakeol

Five β-ketoalkyl 2-(1-dimethylaminoethyl)phenyl sulfoxides (2a-e) were prepared by lithiation at the α-methyl hydrogen to the sulfoxide group of N, N-dimethyl-1-(2-methylsulfinylphenyl)ethylamine (1), followed by condensation with esters. The reduction of 2a-e gave two kinds of β-hydroxysulfoxides (3a-e and 4a-e), whose structures were determined by transforming 4a to naturally occurring (-)-matsutakeol. The results on the diastereoselectivity of this reduction and the 1H-NMR spectral behavior of the α-hydrogens to the sulfoxide group were different from those found in the case of reduction of β-ketoalkyl tolyl sulfoxides.