title: Methanetrisamidines in coordination chemistry--syntheses, structures and CH-NH tautomerism.
abstract: Methanetrisamidines {HC[C(NR)NHR]3} (R = i-Pr 1a; Ph 1b) were reacted with different metal complexes. Reaction of 1a with NiCl2(H2O)6 occurred with protonation of 1a and formation of {[C(C(NHi-Pr)2)3](2+)[NiCl4](2-)} 2, whereas the reaction with CuCl gave [C(C(N(i-Pr)CuCl)NHi-Pr)2(C(NHi-Pr)2)] 3. The formation of 2 and 3, which contain the N-H tautomeric form of 1a, occurred with H-migration from carbon to nitrogen. In contrast, reactions of 1b with [M(NCMe)3(CO)3] (M = Cr, Mo, W) yielded octahedral complexes fac-[M(CO)3CH(C(NHPh)NPh)3] (M = Cr 4a, Mo 4b, W 4c), in which the C-H tautomeric form is preserved. 1b is a rather strong σ-donor ligand as was shown by IR spectroscopy. The structures of 2, 3 and 4a were determined by single crystal X-ray diffraction.
authors.affiliation: University of Duisburg-Essen, Universitätsstr. 5-7, S07 S03 C30, 45117 Essen, Germany. stephan.schulz@uni-due.de.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Gutschank
authors.forename: Stephan
authors.initials: S
authors.lastname: Schulz
authors.forename: Dieter
authors.initials: D
authors.lastname: Bläser
authors.forename: Christoph
authors.initials: C
authors.lastname: Wölper