Sn(ii)–carbon bond reactivity: radical generation and consumption via reactions of a stannylene with alkynes

Abstract

Thermal Sn–C cleavage in the diarylstannylene Sn(Ar^iPr4)₂ (Ar^iPr4 = C₆H₃-2,6-(C₆H₃-2,6-iPr₂)₂) was used to generate ˙Sn(Ar^iPr4) and ˙Ar^iPr4 radicals for alkyne arylstannylation. The radical pair and RCCR′ (R = H, R′ = Ph; R = Ph, R′ = Ph; R = H, R′ = C₄H₉; R = H, R′ = SiMe₃) in refluxing benzene generate the aryl vinyl stannylene complexes, Ar^iPr4Sn{C(C₆H₅)-C(H)(Ar^iPr4)} (1), Ar^iPr4Sn{C(C₆H₅)-C(H)(C₆H₅)} (2) and Ar^iPr4Sn{C(C₄H₉)-C(H)(Ar^iPr4)} (3) respectively. For HCCSiMe₃, the known distannene {Sn(CCSiMe₃)Ar^iPr4}₂ (4) was also generated from this new method.