Fe(III)/NaBH4-mediated free radical hydrofluorination of unactivated alkenes
Timothy J Barker1, Dale L Boger
1Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Abstract:
A powerful Fe(III)/NaBH(4)-mediated free radical hydrofluorination of unactivated alkenes is disclosed using Selectfluor reagent as a source of fluorine and resulting in exclusive Markovnikov addition. In contrast to the traditional and unmanageable free radical hydrofluorination of alkenes, the Fe(III)/NaBH(4)-mediated reaction is conducted under exceptionally mild reaction conditions (0 °C, 5 min, CH(3)CN/H(2)O). The reaction can be conducted open to the air and with water as a cosolvent and demonstrates an outstanding substrate scope and functional group tolerance.
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