Bis(phosphinimino)amide supported borondihydride and heteroleptic dihalo compounds of group 13

Abstract

Abstract The reaction of tetraphenyldiphosphazane (Ph2P)2NH with mesityl azide 2,4,6-Me3C6H2-N3 affords a new [N,N′] chelating ligand, [HN(Ph2PN(2,4,6-Me3C6H2))2] (LH). The ligand can be easily deprotonated by using nBuLi or Li[N(SiMe3)2] in Et2O to yield [{N(Ph2PN(2,4,6-Me3C6H2))2}Li·OEt2] (1). The reaction of LH with AlMe3 and BH3·SMe2, respectively, gives the corresponding mononuclear complexes [{N(Ph2PN(2,4,6-Me3C6H2))2}AlMe2] (2) and a rare borondihydride [{N(Ph2PN(2,4,6-Me3C6H2))2}BH2] (3). Similarly, reaction of 1 with the trihalides, MX3, of group 13 elements afford the corresponding dihalo complexes, [{N(Ph2PN(2,4,6-Me3C6H2))2}MX2] [M = B, X = F (4); M = Al, X = Cl (5); M = Ga, X = Cl (6); M = In, X = Br (7)]. All the complexes reported in this work have been isolated in good yields and are expected to serve as useful synthons in a number of reactions. The solid-state structure of LH and 1-7 have been investigated by single-crystal X-ray structural analysis. Synthesis of a rare borondihydride complex has been made possible through the use of a relatively strong donor monoanionic bis(phosphinimino)amide ligand. Crucially, the ligand backbone is void of any reactive acidic hydrogen. The same ligand has also made feasible the synthesis of some heteroleptic dihalo derivatives of group 13 elements