Main Group Compounds as Amphoteric Ligands to Transition Metals. Synthesis and Molecular Structure of Cr(CO)5 PPh2CH2Ga (CH2CMe3)2. NMe3.

The reactivities of the group 13 compounds, R2MCH2PPh2 and R2MPPh2, as amphoteric ligands to transition metals have been investigated. The ligands R2MCH2PPh2 (R = CH2CMe3, CH2SiMe3; M = Ga, In) reacted readily with Cr(CO)5NMe3 in benzene solution to form Cr(CO)5[PPh2CH2MR2·NMe3], whereas for ligands of the type R2MPPh2 (R = CH2CMe3, CH2SiMe3; M = Al, Ga, In), only the two aluminum compounds and (Me3CCH2)2GaPPh2 formed isolable products of the type Cr(CO)5[PPh2MR2·NMe3]. However, the gallium and indium ligands with (trimethylsilyl)methyl substituents (Me3SiCH2)2MPPh2 reacted with NEt4MT(CO)5Cl (MT = Cr, Mo, W) to form products of the type NEt4MT(CO)5[PPh2MR2Cl]. All new compounds were characterized by their physical properties, C and H analyses, and 1H and 31P NMR and IR spectral properties. The identity of NEt4Cr(CO)5[PPh2In(CH2SiMe3)2Cl] was further confirmed by the subsequent identification of products from reactions with anhydrous HCl and with MeI. In addition, Cr(CO)5[PPh2CH2Ga(CH2CMe3)2·NMe3] was cha...