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Thin films of zirconium carbonitride have been deposited on glass at 600 °C from two novel guanidinate precursors: [ZrCp′{η2-(iPrN)2CNMe2}2Cl] (1) and [ZrCp′2{η2-(iPrN)2CNMe2}Cl] (2) (Cp′ = monomethylcyclopentadienyl). Both compounds 1 and 2 were structurally characterized by X-ray crystallography. The films grown via low pressure chemical vapor deposition (LPCVD) from compound 1 were mirror-like with a red-brown sheen whereas those from 2 were gray. Chlorine was present in the films although the levels were no higher than 3 at.%. These two compounds clearly show how the coordination environment around the metal center affects the composition of the film, as films from 1 were nitrogen rich and those from 2 were carbon rich. The films were uniform, adhesive, abrasion resistant, conformal, and hard, being resistant to scratching with steel and brass scalpels.

Some new N,N‘-bis(aryl)imidazolinium salts (3a−h), in which the N-aryl groups have one unsubstituted ortho position and alkyl (Me, Pri) or alkoxy (OMe, OPri) substitution at the other ortho and/or para positions, have been prepared. They were used for the synthesis of N-heterocyclic carbene complexes of palladium in which the N-heterocyclic carbene is attached to cyclometalated or electron-rich aromatic rings (4, 5, 11d,e). The reaction of Pd(tmed)(CH3)2 with the N-heterocyclic carbene generated from 3b and base gave the dimethyl complex 6, which quantitatively eliminated ethane to form the Pd(0) complex 7. The latter was converted to a new type of “pincer” complex (8) by facile cyclometalation of both aromatic groups of the N-heterocyclic carbene ligand. The activities of the new complexes 4 and 9d,e in the Heck reaction of aryl halides were compared. At higher temperatures the complexes 9d,e show low activity in the coupling of aryl chlorides.

Dimethylindenyl-functionalized N-heterocyclic carbene complexes of titanium(IV), titanium(III), zirconium(IV), and vanadium(III) were prepared from potassium indenylcarbenes by salt elimination reactions. X-ray diffraction studies revealed that in the complexes the ligand adopts a bidentate coordination mode. Alkanolysis of a dimethylindene-functionalized imidazolium salt with Y(CH2SiMe3)3(THF)2 gave rise to a dimeric yttrium bromo alkyl in which the ligand adopts a bidentate coodination mode. Aminolysis of the fluorene-functionalized imidazolium salts with {[Cr(N(SiMe3)2)2(THF)2} led to chromium(II) complexes in which the ligand adopts a monodentate binding mode via the N-heterocyclic carbene end with dangling fluorene groups.