Trends in volatility with changes in the halide ligand were established for gold(I) complexes of the type X-Au-L [X = Cl, Br, I; L = CNBu, CNMe, PMe, P(NMe), P(OCHCF)] by determining the temperatures for the onset of sublimation (T) at a fixed pressure. Within each series of isocyanide complexes, T decreases with increasing atomic radius of the halide, making the iodide complex the most volatile. For the phosphine and phosphoramidate complexes, the chloride and bromide have similar T values with the bromide slightly higher, but the iodide complex is again the most volatile of the three. The trends in volatility can be correlated to variation in Au-Au bond distances and aggregation patterns in the solid state structures. For the P(OCHCF) complexes, melting occurred before sublimation, but the iodide complex was still more volatile than the bromide. These trends have implications for the use of these complexes in electron beam induced deposition and chemical vapor deposition, for which precursor volatility is important.

This report describes the synthesis and characterization of a new series of group 4 complexes supported by a trianionic ONO3– pincer-type ligand. Treating TiCl4 with the proligand [CF3–ONO]­H3 (1) and NEt3 in benzene afforded {[CF3–ONO]­TiCl3}­{HNEt3}2 (2). By means of a lithium transmetalation route, the neutral monochloride complex [CF3–ONO]­TiCl­(THF) (3) was synthesized in 91% yield. The analogous Hf­(IV) derivative could not be obtained using this method. Instead, transmetalation with thallium­(I) resulted in the formation of the seven-coordinate complex [CF3–ONHO]­HfCl2(THF)2 (4-(THF) 2 ), which was characterized by combustion analysis and X-ray crystallography. Applying vacuum to 4-(THF) 2 liberated the THF ligands to provide the five-coordinate THF-free complex [CF3–ONHO]­HfCl2 (4). Alkylation of complex 4 with alkyllithium or Grignard reagents resulted in a mixture of unidentifiable products. However, access to the neutral complex 3 enabled the subsequent preparation of organotitanium complexes [CF3–ONO]­TiR­(THF) (5-R; R = Me, Bn, Mes). Single-crystal X-ray analysis of 5-Me indicated that the organotitanium complexes are mononuclear. Single-crystal X-ray diffraction and NMR studies in solution confirmed that complex 5-Mes exhibits rare through-space 19F–19F coupling (5 Hz).

The title compound is an LiBr-bridged TiIV alkoxide dimer, supported by a novel monoanionic [NNN] pincer-type ligand. The bis­[2-(1-imino-2,2-di­methyl­prop­yl)-4-methyl­phen­yl]amine ligand is the first reported ligand that bears hydrogen atoms on its ketimine side arms.