Synthesis and Reactivity of Donor-Stabilized Bis(pentafluoroethyl)stannylene [Sn(C2 F5 )2 (D)n ] (D=THF, DMAP, PMe3 , [Sn(C2 F5 )3 ]- ).

In this contribution we report on the synthesis of bis(pentafluoroethyl)stannane, H2 Sn(C2 F5 )2 . In the reaction with donor molecules a ready elimination of hydrogen and the formation of the corresponding donor-stabilized monomeric bis(pentafluoroethyl)stannylene, Sn(C2 F5 )2 , becomes apparent. With dependence on the Lewis basicity and steric demand of the donor, varying coordination numbers are realized. Whereas the reaction with nitrogen bases like 4-(dimethylamino)pyridine (DMAP) leads to the complexation of two donor molecules, [Sn(C2 F5 )2 (dmap)2 ], treatment with PMe3 or [Sn(C2 F5 )3 ]- furnished the corresponding neutral or anionic monoadducts, [Sn(C2 F5 )2 (D)] (D=PMe3 , [Sn(C2 F5 )3 ]- ). In contrast, the utilization of sterically demanding donors, such as iPr2 O, as well as the thermal treatment of ether complexes, [Sn(C2 F5 )2 (D)n ] (D=Et2 O, THF), leads to the formation of oligomeric and cyclic stannylene moieties [Sn(C2 F5 )2 ]n . The reactivity of H2 Sn(C2 F5 )2 and the donor-stabilized stannylenes was proven by hydrostannylation and complexation reactions with tetracarbonylnickel and bimetallic compounds. In the latter case, a donor-dependent stannylene or distannylene insertion into the metal-metal bond was observed.