A New Series of Mono- and Dinuclear Hydridosilylrhodium(III) Complexes, RhCl(H)(SiAr₃)L₂and RhL(SiAr₃)H(μ-Cl)(μ-H)RhH(SiAr₃)L (L = P(i-Pr₃)). Preparation by Oxidative Addition of HSiAr₃and Molecular Structures of the Complexes

Abstract

Reactions of triarylsilanes such as HSiPh3, HSi(C6H4Me-p)3, HSi(C6H4OMe-p)3, HSi(C6H4Cl-p)3, HSi(C6H4F-p)3, and HSi(C6H4CF3-p)3 with RhClL2 (L = P(i-Pr)3) give a series of hydrido(triarylsilyl)rhodium(III) complexes, RhCl(H)(SiAr3)L2 (1, Ar = Ph; 2, Ar = C6H4Me-p; 3, Ar = C6H4OMe-p; 4, Ar = C6H4Cl-p; 5, Ar = C6H4F-p; 6, Ar = C6H4CF3-p). Tris(phenylethynyl)silane also reacts with the Rh(I) complex to give another oxidative-addition product, RhCl(H)[Si(C⋮CPh)3]L2 (7). X-ray analyses of 1 and 7 show a distorted-square-pyramidal coordination around the Rh center with the silyl ligand at the apical position. Prolonged reactions of HSiPh3 and of HSi(C6H4OCF3-p)3 with RhClL2 give dinuclear complexes, RhL(SiAr3)H(μ-Cl)(μ-H)RhH(SiAr3)L (8, Ar = Ph; 9, Ar = C6H4OCF3-p). X-ray crystallography of 9 shows a molecular structure containing two Rh centers bridged with hydrido and chloro ligands. 1,1,3,3-Tetraisopropyldisiloxane undergoes oxidative addition of the SiH bonds to RhClL2 to give a symmetric dinuclear Rh(III) complex with bridging hydrido, chloro, and disiloxanyl ligands, RhL(H)(μ-H)(μ-Cl)[μ-(i-Pr)2SiOSi-(i-Pr)2]Rh(H)L (10).

Rhodium(I) Complexes with π-Coordinated Arylallene. Structures in the Solid State and in Solution and Reaction with Arylallene To Give Rhodacyclopentane

“…Manipulations of the Rh complexes were carried out under nitrogen or argon using standard Schlenk techniques. RhCl(PMe 3 ) 3 , [Rh(μ-Cl)(PMe 3 ) 2 ] 2 , RhCl(PPh 3 ) 3 , RhCl[P( i -Pr) 3 ] 2 , RhClH(SiPh 3 )[P( i -Pr) 3 ] 2 , and arylallenes were prepared according to the literature …”

Thermal Si−C Bond Cleavage of LRhH(SiAr3)(μ-H)(μ-Cl)RhH(SiAr3)L (Ar = C6H5, C6H4F-p; L = P(i-Pr)3) To Give LRhH(μ-SiAr3)(μ-SiAr2)(μ-Cl)RhHL Containing Symmetrically Bridging Triarylsilyl and Diarylsilylene Ligands

“…Exchange Reaction of LRhH(SiPh 3 )( μ -H)( μ -Cl)RhH(SiPh 3 )L (1) with Triarylsilane at Room Temperature. LRhH(SiPh 3 )(μ-H)(μ-Cl)RhH(SiPh 3 )L ( 1 , L = P( i -Pr) 3 ) reacts with HSi(C 6 H 4 F- p ) 3 in a 1:10 molar ratio at room temperature to give LRhH[Si(C 6 H 4 F- p ) 3 ](μ-H)(μ-Cl)RhH[Si(C 6 H 4 F- p ) 3 ]L ( 2 ) in 78% yield, as shown in eq 1. The molecular geometries of 1 and 2 are shown in Figures and , respectively.…”

Isomers of Chloro(triarylsilyl)hydridorhodium(III) Complexes, mer-RhCl(H)(SiAr3)(PMe3)3. Relevance of Their Structures to Reductive Elimination of ClSiAr3

“…The intramolecular coupling of the ligands seems to be significantly influenced by the coordination geometry. Recently, we have observed facile formation of chlorotriorganosilane from RhCl(H)(SiR 3 )[P( i -Pr) 3 ] 2 containing a labile pentacoordinated metal center at room temperature . On the other hand, mer -RhCl(H)(SiHAr 2 )(PMe 3 ) 3 , whose chloro and diarylsilyl ligands are at mutually trans positions of the rigid octahedral coordination, gives fac -RhH 2 (SiClAr 2 )(PMe 3 ) 3 as a product of the thermal reaction, as shown in Scheme …”