Phenylselenyl alkanes

A further interesting example is the conversion of the alkynes 244 (Scheme 39) into the a-ketoacetals 247 [118]. The reaction with phenylselenyl sulfate affords the product of double addition 245, which is deselenenylated by the excess of persulfate to give the tetramethoxy alkane 246. During work up deprotection occurs and compounds 247 are produced. The reaction occurs equally well with internal alkynes. Interesting enough, methyl ketones 248 reacted, under the same experimental conditions, to afford the same a-ketoacetals... 

Scheme 38. Phenylselenyl Sulfate Catalyzed One-Pot Conversions of Vinyl Halides into Alkoxy Acetals and of Styrene Derivatives into 1,1- and 1,2-Dialkoxy Alkanes...

Further, the recently developed one-pot procedure (Vol 6, p. 208) for the synthesis of nitro-alkenes from nitro-alkanes via phenylselenylation and subsequent oxidative elimination has been improved and extended to provide 1-nitro-l-hydroxymethyl-alkenes in excellent yield (Scheme 34). ... 

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