N. Thirupathi et al., Group 5 transition metal imido complexes with dianionic guanidinate ligands displaying extended interactions, CHEM COMMUN, (24), 1999, pp. 2483-2484
N,N',N "-tri(isopropyl)guanidinate complexes of M(v) (M = Nb, Ta) bearing i
mido ligands represent unique examples of monoanionic and dianionic guanidi
nate complexes of these metals; single crystal X-ray analyses for two of th
e latter species, {[mu-(NPri)(3)C](2)TaMe(NPri)}(Mg2Cl2). 4C(6)D(6) and {(m
u-eta(2):eta(2) ((PrN)-N-i)(3)C)Ta(NPri)Cl}(2), exhibit unusual bonding mod
es involving all of the nitrogen centers of the ligand.