M is selected from a metal or metalloid, Q is a halogen radical, R is a monovalent aromatic organic radical, R1 is a divalent aromatic organic radical, R2 and R4 are monovalent organic aliphatic radicals selected from alkyl, cyclo alkyl and substituted alkyl, R3 and R5 are polyvalent organic radicals forming a heterocyclic or fused ring structure with E or G, D is a halogen radical, such as I, E i