Expanding organoboron chemistry: epoxidation of potassium organotrifluoroborates.
Most organoboron reagents are highly susceptible to oxidation by a variety of oxidants. In these processes, the valuable carbon-boron bond is cleaved. The organotrifluoroborates examined in this contribution appear resistant to many common oxidants. Consequently, thioether-substituted alkyltrifluoroborates can be oxidized to the corresponding sulfones, while retaining the trifluoroborate moiety. 1-Trifluoroboratoalkenes are oxidized by dioxirane, providing air-stable, crystalline oxiranyltrifluoroborates. These interesting materials are structurally analogous to oxiranyl anions, unstable intermediates that would otherwise be of tremendous synthetic utility. Finally, the first Suzuki-Miyaura coupling of an epoxytrifluoroborate has been accomplished. The chemistry described begins to expand organoboron chemistry in significant new directions.
Molander
Gary A
GA
Roy and Diana Vagelos Laboratories, Department of Chemistry. University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. gmolandr@sas.upenn.edu
Ribagorda
María
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