Sulfenyl groups carbonyl compounds

The a-seleno and a-sulfenyl carbonyl compounds prepared by this reaction can be converted to a,P-unsaturated carbonyl compounds (17-11). The sulfenylation reaction has also been used as a key step in a sequence for moving the position of a carbonyl group to an adjacent carbon. ... 

Heterofunctionalisation of carbonyl compounds in the a-position has become an important facet of oiganocatalytic enamine-mediated reactions. In 2005, the Jorgensen group described asymmetric a-sulfenylation of aliphatic aldehydes using TMS-protected prolinol catalysts. The best sulfenylating agent was M-benzylsulfanyl-1,2,4-triazole. Other catalysts, such as proline, prolinol, prolinamide or other secondary amide were less effective. The catalyst with bulkier aromatic groups (C2a) afforded the most enantioselective reaction (Scheme 8.39). 

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