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Synthesis 2010(6): 911-913
DOI: 10.1055/s-0029-1218631
DOI: 10.1055/s-0029-1218631
SHORTPAPER
© Georg Thieme Verlag
Stuttgart ˙ New York
Improved Synthesis of the Benzyne Precursor 2-(Trimethylsilyl)phenyl Trifluoromethanesulfonate
Further Information
Received
12 November 2009
Publication Date:
04 January 2010 (online)
Publication History
Publication Date:
04 January 2010 (online)
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
- 1
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References
Compound 1 costs more than NZ$ 210 for 5 g (Sigma-Aldrich).
11Very 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.