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Photosensitized oxygenation of Nb-methoxycarbonyltryptamine (1) in the presence of (-)-nicotine followed by treatment with triphenylphosphine gave Nb-methoxycarbonyl-1,2,3,3a,8,8a-hexahydro-3a-hydroxypyrrolo[2,3-b]indole (2) with modest enantioselectivity. Determination of absolute configuration of 2 was also described.

Reactions of aliphatic ketones with lithium trimethylsilyl-diazomethane in the presence of excess olefins afforded methylenecyclopropanes in moderate to good yields. The multiplicity of the alkylidene carbene intermediate in the reacting state has been revealed to be a singlet.

(Rc,Ss)-1,1,1-trifluoro-3-(p-tolylsulfinyl)-2-propanol (>99% e.e.), an important reagent for the asymmetric protonation of substituted enolates, was prepared (70%) from (S)-methyl p-tolyl sulfoxide. The stereoselectivity of the Yamdazyma farinosa-catalyzed reduction of carbonyl groups, the key step for the introduction of an asymmetric carbon, was greatly affected by the stereochemistry of the asymmetric sulfur atom. The reduction of (S)-1,1,1-trifluoro-3-(p-tolylsulfinyl)-2-propanone proceeded smoothly and in a quite stereoselective manner to give the desired compound, while a 76 : 24 mixture of (Rc,Rs)- and (Sc,Rs)-isomers was obtained from the substrate with the opposite (R)-configuration.