Methylene Bridged Group 13-15 Compounds, R2MCH2PPh2 (R = CH2CMe3, CH2SiMe3; M = Ga, In). Crystal Structure of ((Me3CCH2)2InCH2PPh2)2.C6D6, a Molecule Containing an In-C-P-In-C-P Ring in a Chair Conformation

Abstract : A series of compounds of the type R2MCH2PPh2 (R = CH2CMe3, CH2SiMe3; M = Ga, In) have been prepared by metathetical reactions between the appropriate diorganometal halide and LiCH2PPH2 in pentane or Et2O at -78 C. All compounds were characterized by physical properties, partial elemental analyses (C, H), cryoscopic molecular weight measurements in benzene solution as well as IR, H NMR and P NMR spectroscopic data. All appropriate data support the existence of dimeric molecules. The monomeric species dimerize by apparent Lewis acid-base interactions. These interactions are sufficiently strong that the compounds do not form stable adducts with oxygen- or nitrogen-containing Lewis bases.