Synthesis and characterization of substituted-allyl-rhodium complexes incorporating bidentate phosphine and phosphinite ligands

Article abstract of DOI:10.1021/ic00136a003

The reaction of (1,5-cyclooctadiene)(2-methylallyl)rhodium(I), [η³-(2-Me-C₃H₄)Rh(COD)], with chelating phosphines and phosphinites results in the smooth displacement of 1,5-cyclooctadiene and the formation of the new (2-methylallyl)rhodium complexes [η³-(2-Me-C₃H₄)RhL₂], where L₂ = Me₂PCH₂CH₂PMe₂, (p-Me-C₆H₄)₂PCH₂CH ₂P(C₆H₄-p-Me)₂, Ph₂PCH₂CH₂CH₂PPh₂, cis-Ph₂PCH=CHPPh₂, (S,S)-Ph₂PCH(CH₃)CH(CH₃)PPh₂, HN(SiMe₂CH₂PPh₂)₂, Ph₂PCH₂CH₂AsPh₂, and (MeO)₂PCH₂CH₂P(OMe)₂, in good yields. Similarly, the reaction of a number of the above chelating ligands with the pure syn isomer of (1,5-cyclooctadiene)(1-methylallyl)rhodium(I), [η³-(1-Me-C₃H₄)Rh(COD)], results in a mixture of the corresponding syn and anti isomers with the syn form predominating. The preparation and spectral characterization of all new compounds are presented together with a discussion of the stereoselectivity of the substitution process.