Aldol Synthesis with an Aqueous Solution of Formalin

Abstract

With an aqueous solution of formalin, aldol reaction of trimethylsilyl enol ether proceeds moderately using tetrabutyl­ammonium fluoride (TBAF). Furthermore, catalytic asymmetric hydroxymethylation with trimethoxysilyl enol ether using water tolerant (R)-BINAP-AgOTf as Lewis acid and KF as Lewis base has been achieved in aqueous media.

Key words

aldol reaction - silyl enol ether - enantioselective - ­BINAP-AgOTf catalyst - formalin aqueous solution

References

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9

The reaction mixture is barely stirrable without being unfrozen.