The first bis(imido) transition metal Schiff-base complexes

The first bis(imido) transition metal Schiff-base complexes [((BuN)-N-t)(2) WL], where L=salen 1, (3,5-Bu-2(t))(2)salen 2 or (4-MeO)(2) salen 3 [salen= dianion of N,N'-bis(salicylidene)ethane-1,2-diamine, (3,5-Bu-2(t))(2)salen= dianion of N,N'-bis(3,5-di-tert-butylsalicylidene)ethane-1,2-diamine and (4 -MeO)(2)salen=dianion of N,N'-bis(4-methoxysalicylidene)ethane-1,2-diamine] were synthesised by alcoholysis of [W(NBut)(2)(NHBut)(2)] using the diprot onated Schiff-bases, LH2, and characterised by H-1 and C-13-{H-1} NMR for 1 -3, and mass spectrometry, elemental analysis, cyclic voltammetry and X-ray crystallography for 2.