Reductive Dehydrogenation of a Stannane via Multiple Sn-H Activation by Frustrated Lewis Pairs.

A bulky substituted stannane Ar*SnH3 (Ar*=2,6-(2',4',6'-triisopropylphenyl)phenyl) was treated with the well-known frustrated Lewis pair (FLP) PtBu3 /B(C6 F5 )3 in varying stoichiometries. To some degree, hydride abstraction and adduct formation is observed, leading to [Ar*SnH2 (PtBu3 )]+ which is rather unreactive toward further dehydrogenation. In a competing process, the FLP proved to be capable of completely striping-off hydrogen and hydrides to generate the first cationic phosphonio-stannylene [Ar*Sn(PtBu3 )]+ . This behavior provides insight into the activation/abstraction mechanism processes involved in these Group 14 hydride derivatives.