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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.