title: Volatile imido-hydrazido compounds of the refractory metals niobium, tantalum, molybdenum, and tungsten.
abstract: Volatile 1,1-dimethyl-2-(trimethylsilyl)hydrazido(1-) complexes of niobium, tantalum, molybdenum, and tungsten have been synthesized and fully characterized for use as precursors in their chemical vapor deposition to metal nitrides. Different reaction patterns were observed in the hydrazinolysis of imido complexes of those four metals with (trimethylsilyl)dimethylhydrazine HN(SiMe3)NMe2 (H-TDMH). [Ta(NtBu)Cl3Py2] gave [Ta(TDMH)2Cl3] (1) with loss of the imido functionality, and [M(NtBu)2Cl2Py2] gave [M(NtBu)2(TDMH)Cl] (M = W, 8a; Mo, 8b). Reactions of both types of metal imido complexes with magnesium hydrazides produced [M(NtBu)(TDMH)2X] (M = Ta, X = Cl, 2a; X = Br, 3a; M = Nb, X = Cl, 2b; X = Br, 3b) and [M(NtBu)2(TDMH)X] (M = W, X = Cl, 8a; X = Br, 9a; M = Mo, X = Cl, 8b; X = Br, 9b). Halogen substitution reactions at 2 and 3 by -NMe2, -NHtBu, and CH2Ph groups as well as imido ligand replacement reactions have been investigated. The results of crystal structure determinations of 1, 4a, 5a, 6a, 7b, and 9b are presented.
authors.affiliation: Fachbereich Chemie and Fachbereich Physik und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universtät Marburg, Hans-Meerwein-Strasse, Marburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Gaess
authors.forename: Klaus
authors.initials: K
authors.lastname: Harms
authors.forename: Michael
authors.initials: M
authors.lastname: Pokoj
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Stolz
authors.forename: Jörg
authors.initials: J
authors.lastname: Sundermeyer