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Chiral non-racemic α-substituted sulfoxides have been allowed to react with O-silylated ketene acetals in the presence of a catalytic amount of ZnI2 in THF to give chiral non-racemic α-siloxy sulfides in >99% ee. This is the highest enantioselectivity reported to date for the Pummerer reaction.

Chiral, non-racemic sulfoxides were reacted with thiols and BSA in the presence of a catalytic amount of TMSOTf in MeCN at rt overnight to give the corresponding chiral, non-racemic anti-thioacetals with high diastereoselectivity.

Various types of syn- and anti-β-substituted sulfoxides 6b–e, g reacted with ketene tert-butyldimethylsilyl acetal 2 in the presence of a catalytic amount of zinc iodide in acetonitrile to give high yields of the corresponding α-siloxy sulfides 7b–e, g stereoselectively. Similarly, chiral, nonracemic sulfoxides 6a, f, h, i reacted with acetal 2 in acetonitrile to give the chiral, non-racemic α-siloxy sulfides 7a, f, h, i in high yields.

The hypervalent iodine oxidation of phenol derivatives bearing aminoquinones at the ortho (9) or meta positions (19) in 2,2,2-trifluoroethanol was investigated with the aim of preparing novel antitumor compounds. Azacarbocyclic spirodienone derivatives (13) or phenol derivatives containing the 2,3-dihydro-1H-azepine systems (17, 20) were selectively obtained by the reaction of these phenol derivatives and the hypervalent iodine reagent, phenyliodine(III) bis(trifluoroacetate). The application of this reaction to phenol derivatives bearing aminoquinones (10−12) is also described.

Treatment of chiral, non-racemic vinyl sulfoxides with O-silylated ketene acetal in the presence of a catalytic amount of zinc chloride in tetrahydrofuran resulted in an enantioselective Pummerer-type reaction, affording a considerable yield of the corresponding enantiomerically enriched methyl 4-siloxy-4-sulfenylbutyrate in 78-82% ee.