Synthese von Alkin-, Alkinyl-und Vinyliden-Rhodium-Komplexen ausgehend von Alkinyltriphenylsilanen [1] / Synthesis of Alkyne, Alkynyl and Vinylidene Rhodium Complexes from Alkynyltriphenylsilanes [1]

Abstract

Abstract Compound [RhCl(PiPr3)2]n (1) reacts with RC≡CSiPh3 to give the rhodium(I) complexes trans-[RhCl(RC≡CSiPh3)(PiPr3)2] (2-5) of which 2 (R = CH3) and 5 (R = C6H5) rearrange thermally to yield the vinylidene isomers trans-[RhCl(=C=C(SiPh3)(R)(PiPr3)2] (6,7). The reaction of 2 and 4 (R = CH2OMe) with NaC5H* affords the cyclopentadienyl complexes [C5H5Rh(RC≡CSiPh3)(PiPr3)] (8,9). The square-planar alkynylrhodium(I) compounds trans-[Rh(C≡CSiPh3)(L)(PiPr3)2] (12,13) are obtained from 10 or 11 on treatment with NaN(SiMe3)2; they react with cyclopentadiene to give [C5H5RhH(C≡CSiPh3)(PiPr3)] (14). Five- and six-coordinate bis(alkynyl)hydridorhodium(III) complexes [RhH(C≡CSiPh3)(C≡CSiR3)(PiPr3)2] (15,16) and [RhH(C≡CSiPh3)(C≡CSiR3)(py)(PiPr3)2] (17,18) are prepared from 12 and 13 by oxidative addition of HC≡CSiR3 (R = CH3, C6H5). The reaction of 12 with Me3SiC≡CCO2Et leads to the formation of trans-[Rh(C≡CSiPh3)(Me3SiC≡CCO2Et)(PiPr3)2] (19).