Pinacolatoboron fluoride (pinBF) is an efficient fluoride transfer agent for diastereoselective synthesis of benzylic fluorides. Issue 23 (3rd June 2015)

• Record Type: Journal Article
• Authors: Cresswell, Alexander J.; Davies, Stephen G.; Figuccia, Aude L.A.; Fletcher, Ai M.; Heijnen, Dorus; Lee, James A.; Morris, Melloney J.; Kennett, Alice M.R.; Roberts, Paul M.; Thomson, James E.
• Is Part Of: Tetrahedron letters. Volume 56:Issue 23(2015)
• Page Start: 3373
• Page End: 3377
• Publication Date: 2015-06-03
• Subjects: Benzylic fluoride -- Epoxide -- Nucleophilic fluorination; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2014.12.044
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: The incorporation of alkoxy ligands within a range of alkoxyfluoroboranes and dialkoxyfluoroboranes results in fluoroborane reagents with attenuated Lewis acidity and increased ability to donate fluoride ion(s) when compared to boron trifluoride itself. Pinacolatoboron fluoride (pinBF), prepared in situ from BF3 ·OEt2 and bis( O -trimethylsilyl)pinacol, has been identified as an efficient fluoride donor which allows highly stereoselective SN 1-type epoxide ring-opening (with retention of configuration) of a range of trans -β-methyl-substituted aryl epoxides to give the corresponding syn -fluorohydrins. The substrate scope of this transformation is more broad than the analogous protocol using boron trifluoride alone.