One-Pot Synthesis of α-Siloxy Esters Using a Silylated Masked Acyl Cyanide

Abstract

Synthesis of α-siloxy esters via a one-pot reaction from various aldehydes and alcohols using a masked acyl cyanide (MAC) reagent bearing tert-butyldimethylsilyl group is described.

Key words

acyl anion equivalents - masked acyl cyanide - α-hydroxy esters - one-pot - intramolecular migration

References

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12

The difference in the reaction rate of methanolysis can be reasonably explained as follows. The broad peaks in NMR spectrum of 12b infer a larger steric repulsion between the β-cholesteryl and C-3 side chain moieties of 12b than that of 12a. Thus, the ester bond of 12b was cleaved faster than that of 12a due to the difference of constraint energies of the ester bonds.