Improved Synthesis of the Benzyne Precursor 2-(Trimethylsilyl)phenyl Trifluoromethanesulfonate

Abstract

An alternate procedure for the preparation of 2-(trimethylsilyl)phenyl trifluoromethanesulfonate, a coveted benzyne precursor, is described. Modifications to existing methods result in a dramatic reduction in the overall reaction time and eliminate the use of organolithium reagents. This new procedure proceeds in four steps in 81% overall yield from 2-chlorophenol.

Key words

benzyne - aryne - precursor

References

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4

Compound 1 costs more than NZ$ 210 for 5 g (Sigma-Aldrich).

11

Very recently, Bronner and Garg reported an ortho-metallation based preparation of 1 from phenol in 3 steps and 66% overall yield: Bronner, S. M.; Garg, N. K.; J. Org. Chem.; in press; DOI: 10.1021/jo90201.