Bis(acyl)phosphide - Ambidentate Ligands for the Synthesis of Group 14 and 15 Main Group Element Compounds.

The reactivity of the bis(acyl)phosphide ion [P(COR) 2 ] - (BAP - , R=Ph, Mes) with silicon halides SiX 4 (X=Cl, Br) and pnictogen chlorides ECl 3 (E=As, Sb and Bi) was investigated. The reaction with SiX 4 leads to the hexacoordinate silanes SiX 2 (BAP) 2 in which BAP - is coordinated in the chelating κ 2 -O,O' mode, analogously to acac - . Unexpectedly, the coordination behaviour of BAP - differs from the one of acac - in the interpnictogen compounds E(BAP) 3 (E=As, Sb) in which the formation of E-P bonds is favoured over κ 2 -O,O' chelation via the oxygen centres. Finally, the reaction of BiCl 3 with three equivalents of Na(BAP) leads to the formation of red, crystalline Bi 2 (BAP) 4 , an air stable dibismuthine, as product of a redox reaction.