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Catalytic Wittig Reactions of Semi‐ and Nonstabilized Ylides Enabled by Ylide Tuning
Author(s) -
Coyle Emma E.,
Doonan Bryan J.,
Holohan Andrew J.,
Walsh Killian A.,
Lavigne Florie,
Krenske Elizabeth H.,
O'Brien Christopher J.
Publication year - 2014
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201406103
Subject(s) - ylide , steric effects , wittig reaction , chemistry , catalysis , selectivity , base (topology) , organic chemistry , medicinal chemistry , combinatorial chemistry , mathematical analysis , mathematics
The first examples of catalytic Wittig reactions with semistabilized and nonstabilized ylides are reported. These reactions were enabled by utilization of a masked base, sodium tert ‐butyl carbonate, and/or ylide tuning. The acidity of the ylide‐forming proton was tuned by varying the electron density at the phosphorus center in the precatalyst, thus facilitating the use of relatively mild bases. Steric modification of the precatalyst structure resulted in significant enhancement of E selectivity up to >95:5, E / Z .