Treatment of -ketoiminates with [(allyl)Pd(µ-Cl)] 2 affords volatile, air-stable allyl( -ketoiminato)palladium(II) complexes. The structure of [(methallyl)Pd(Phacac)] (Phacac ) MeCOCHCMeNPh) was determined by single-crystal X-ray diffraction. In solution 1 H NMR analyses indicate either a direct rotation of a planar allyl ligand about the allyl-palladium axis or a solvent-assisted exchange process involving the transient formation of a monodentate ketoiminato ligand. The physical properties of the complexes were modified by altering the -ketoiminato or the η 3 -allyl ligands. Some derivatives are liquid at room temperature and were known to be suitable for chemical vapor deposition of Pd thin films.The preparation of thin films of palladium by metal organic chemical vapor deposition (CVD) is becoming increasingly attractive for the fabrication of electronic devices 1 because such films have potentially useful applications in replacing gold as electrical contacts in integrated circuits and in making gas sensors, magnetooptical data storage devices, etc. 2 The largest obstacle to CVD of Pd films has been the lack of suitable precursors, as most volatile Pd complexes suffer from poor stability in air and moisture. 3 Recently, this problem was partially overcome by Puddephatt, who reported the preparation of volatile allyl( -diketonato)-palladium(II) complexes, which are liquid and stable at room temperature and are excellent CVD precursors for Pd films. 4 In view of these results, we felt it desirable to investigate analogous complexes having -ketoiminate ligands, which allow for organic functional group variation on the imine nitrogen as a possible way to finetune physical and chemical properties. In this article, we report the synthesis and characterization of such -ketoiminato complexes and a preliminary investigation of their application in the generation of Pd films. Experimental SectionGeneral Information and Materials. Infrared spectra were recorded on a Perkin-Elmer 2000 FT-IR spectrometer. 1 H and 13 C NMR spectra were recorded on a Bruker AM-400 or AMX-300 instrument. Mass spectra were obtained on a JEOL SX-102A instrument operating in fast atom bombardment (FAB) mode. Thermogravimetric analyses were made with a Seiko TG/DTA 300 instrument. Melting points were determined using Seiko SSC 5000 differential scanning calorimetry. Elemental analyses were performed at the NSC

Treatment of the tetrametallic carbido-benzofuryl cluster (C 5 Me 5 )WOs 3 (µ 4 -C)(µ-H) 2 (µ-C 8 H 6 O)(CO) 9 (1) with pressurized CO gas affords a carbido cluster (C 5 Me 5 )WOs 3 (µ 4 -C)(µ-H)(CO) 11 (2) in nearly quantitative yield. The reactions of 2 with diisopropyl acetylenedicarboxylate (DPAD) are investigated. If complex 2 is first treated with Me 3 NO, the incorporation of DPAD at room temperature affords a cluster compound (C 5 Me 5 )-WOs 3 (CO) 10 [C 3 H(CO 2 Pr i ) 2 ] (3) in moderate yield, in which the allyl group is formed by hydride migration to the carbide. Complex 3 undergoes a facile metathesis to yield an isomer (4) with a different arrangement of the allyl C 3 backbone. Upon thermolysis, complex 4 converts to a η 6 -tetramethylfulvene complex [C 5 Me 4 (CH 2 )]WOs 3 (µ-H)[C 3 H(CO 2 Pr i ) 2 ](CO) 9 ( 5) by activation of a ring-methyl in the C 5 Me 5 ligand and a trialkylidyne cluster (C 5 Me 5 )WOs 3 (µ 3 -CH)(µ 3 -CCO 2 Pr i ) 2 (CO) 9 (6) by cleavage of two allyl C-C bonds. The possible mechanism of their interconversion is discussed. If the reaction of the Me 3 NO-activated complex 2 and DPAD is carried out in refluxing toluene, we obtained one more compound (C 5 Me 5 )-WOs 3 [CC 2 (CO 2 Pr i ) 2 H](CO) 10 (7) in low yield, which appears to form through a secondary process involving hydride migration to the DPAD molecule instead.

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