Preparation and Reactivity Studies of Four and Five coordinated Amidinate Aluminum Compounds

Synthesis of four and five coordinated aluminum amidinate (PhC(NtBu)2=L) compounds are reported herein along with their single‐crystal X‐ray structures and detailed characterizations using both, experimental and computational techniques. LAlCl2 (1) and L2AlCl (2) were synthesized by treating AlCl3 with PhC(NtBu)2Li in an equivalent ratio of 1 : 1 and 1 : 2, respectively. [LAl(C2H5)Cl] (3) was prepared from a reaction of AlCl2(C2H5) with PhC(NtBu)2Li in an equivalent ratio of 1 : 1. Reactivity of 3, an amidinate based organo‐aluminum compound is explored for the various reactions. 3 produced [LAl(C2H5)(μ‐F)]2 (4) on treatment with Me3SnF. Interestingly, [LAl(C2H5)Cl] (3) was converted to [LAlCl(μ‐OEt)]2 (5) when refluxed in Et2O. 3 gives the monomeric and neutral cyclic (alkyl)(amino) carbene (cAAC) based radical [LAl(C2H5)(cAAC)] (6) on reduction with KC8 in the presence of cAAC.