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The mixed ligand complexes [{Gd(OCMe2-i-Pr)2Cp}2], [{Sm(OCMe2-i-Pr)2Cp}2], and [Sm2(OCMe2-i-Pr)3Cp3] were synthesized by reacting [LnCp3] with HOCMe2-i-Pr. X-ray crystallographic studies show that the three complexes each have two bridging alkoxide ligands linking two metal atoms. The coordination geometries at the metals are distorted tetrahedral.

Reaction of CeCl3 with an excess of LiTMP (TMP-H = 2,2,6,6-tetramethylpiperidine) gave [Ce(μ-OCH CH2)(TMP)2]2. The alkoxide ligand originated from THF, which was used as the solvent in the reaction. CeCl3 reacted with 3 equiv. of LiTMP in THF to produce, after crystallization, a 3:2 crystalline mixture of Ce(TMP)3 and [Ce(μ-OCH CH2)(TMP)2]2. Ce(TMP)3 could not be isolated cleanly or separated from the mixture except by handpicking the crystals under a microscope. The homoleptic amide complex Ce[N-t-Bu(SiMe3)]3 was obtained by reacting CeCl3(THF)2 with 3 equivalents of LiN-t-Bu(SiMe3). In the solid state, [Ce(μ-OCH CH2)(TMP)2]2 is a dimer with a Ce(μ-OR)2Ce four-member ring, while Ce(TMP)3 and Ce[N-t-Bu(SiMe3)]3 are trigonal planar monomers. There is structural evidence to suggest the presence of a Ce–vinyl group interaction in [Ce(μ-OCH CH2)(TMP)2]2.

Chlorotris(trimethylhydrazido)titanium, TiCl(NMeNMe2)3, was synthesized by reacting TiCl2(NMeNMe2)2 with 1 equiv. of LiNMeNMe2. Tetrakis(trimethylhydrazido)zirconium and hafnium, M(NMeNMe2)4, were prepared from MCl4 and 4 equiv. of LiNMeNMe2 but Ti(NMeNMe2)4 could not be prepared cleanly from TiCl4. Instead, it was synthesized from TiCl(NMeNMe2)3 and LiNMeNMe2. X-ray crystallographic studies show that TiCl(NMeNMe2)3 and Ti(NMeNMe2)4 have three bidendate hydrazide ligands and Zr(NMeNMe2)4 has four bidendate ligands.

The bulky hydrazine t-BuN(H)NMe 2 was synthesized via hydrazone and t-BuN(H)N(H)Me intermediates as the major component in a 90:5:5 mixture consisting of t-BuN(H)NMe 2 , t-BuN(Me)N(H)Me, and t-BuN(Me)NMe 2 . Reacting the mixture with n-BuLi followed by distillation and fractional crystallization led to the isolation of the ligand precursor LiN(t-Bu)NMe 2 . Lithium hydrazides, LiN(R)NMe 2 , were reacted with metal chlorides to afford the hydrazide complexes M(N(Et)Nme 2 ) 4 (M = Zr or Hf), MCI(N(R)NMe 2 ) 3 (M = Zr, R = i-Pr or t-Bu; M = Hf, R = t-Bu), and TaCl 3 (N(i-Pr)NMe 2 ) 2 . The X-ray crystal structures of [LiN(i-Pr)NMe 2 ] 4 , [LiN(t-Bu)NMe 2 -THF]2, ZrCl(N(R)NMe 2 ) 3 (R = i-Pr or f-Bu), and TaCl 3 (N(i-Pr)NMe 2 ) 2 were determined. The structural analyses revealed that the hydrazide ligands in ZrCl(N(R)NMe 2 ) 3 (R = i-Pr or t-Bu) and TaCl 3 (N(I-Pr)Nme 2 ) 2 are η 2 coordinated.

Zirconium amide-iodide complexes were synthesized for possible use as chemical vapor deposition precursors to zirconium nitride films. The series of six complexes Zr(NR(2))(4-n)I(n)(R = Me or Et; n = 1-3) was prepared by reacting ZrI(4) and Zr(NR(2))(4) in hot toluene. X-ray crystallographic analyses were performed for Zr(NMe(2))(3)I, Zr(NEt(2))(2)I(2), and Zr(NEt(2))I(3). In the solid state, Zr(NMe(2))(3)I and Zr(NEt(2))(2)I(2) are the discrete dimers [Zr(NMe(2))(2)I(mu-NMe(2))](2) and [Zr(NEt(2))(2)I(mu-I)](2), and Zr(NEt(2))I(3) is the polymer of dimers ([Zr(NEt(2))I(2)(mu-I)](2))(n). In solution, Zr(NEt(2))(3)I is proposed to be monomeric on the basis of NMR data and a molecular weight determination. The complex Zr(NEt(2))(3)I is the most promising precursor candidate because of its physical properties.