Activation of Alkyl C–F Bonds by B(C₆F₅)₃: Stoichiometric and Catalytic Transformations

Abstract

The Lewis acid B(C6F5)3 is shown to activate a series of alkyl fluorides. In stoichiometric reactions, treatment of sterically demanding phosphines with B(C6F5)3/alkyl fluorides gives phosphonium fluoroborate salts while treatment of B(C6F5)3/alkyl fluorides with the salts [tBu3PX][XB(C6F5)3] (X = H, PhS) gives the alkane and the salt byproduct [tBu3PX][FB(C6F5)3]. These fluoroalkanes are also catalytically converted to the corresponding alkanes by reaction of the fluoroalkane and Et3SiH using B(C6F5)3 as the catalyst.