Stannylalkynes as Starting Materials for the Synthesis of Vinylidene Rhodium Complexes and of Heterodimetallic Compounds Containing a Rh—Hg or Rh—Sn Bond

Reaction of [RhCl(P i Pr 3 ) 2 ] n ( 1 ) with stannylalkynes RCCSnPh 3 [R = H, Me, Ph, CH 2 OH, CH 2 OMe, CMe 2 OH, CH(Me)OH, CH(Ph)OH, SiMe 3 , SnPh 3 ] gives the vinylidenerhodium(I) complexes trans ‐[RhCl(=C=C(SnPh 3 )R)(P i Pr 3 ) 2 ] ( 2a–j ) in good to excellent yields. These compounds react with protic acids to give trans ‐[RhCl(CCHR)(P i Pr 3 ) 2 ] and, for R = CH(Ph)OH, to give the allenylidene complex trans ‐[RhCl(CCCHPh)‐(P i Pr 3 ) 2 ] ( 5 ). On treatment of 2b–j with PhHgCl, the heterodimetallic compounds [Rh(CC̊)(HgPh)Cl(P i Pr 3 ) 2 ] ( 6a–i ) are formed. The bis(alkynyl)rhodium(III) complexes [RhH(CCSi‐Me 3 )(CCSnPh 3 )(py)(P i Pr 3 ) 2 ] ( 9 ) and [Rh(CCSiMe 3 )(CCCH 2 OMe)(SnPh 3 )(P i Pr 3 ) 2 ] ( 10 ) are prepared from trans ‐[Rh‐(CCSiMe 3 )(L)(P i Pr 3 ) 2 ] ( 7, 8 , L = py, C 2 H 4 ) and HCCSnPh 3 or Ph 3 SnCCCH 2 OMe, respectively. The crystal and molecular structures of trans ‐[RhCl(CC(SnPh 3 )CH 2 OMe)(P i Pr 3 ) 2 ] ( 2e ) and [Rh(CCCH 2 OMe)(HgPh)Cl(P i Pr 3 ) 2 ] ( 6d ) have been determined.