Bis benzonitrile dichloroplatinum

Benzonitrile (75 mL) is placed in a 250-mL round-bottomed flask and heated to 100 °C. Anhydrous platinum(II) chloride (2.66 g, 10.0 mmol) is added in small portions, while the mixture is stirred magnetically. A light brown solution is formed. Ten minutes after all the platinum chloride has been added, the solution is Altered while still hot, and the Altrate is collected in a 1-L Erlenmeyer flask. A precipitate begins to form on cooling, and the slow addition of 500 mL of petroleum ether completes the precipitation. The pale yellow product is Altered through a Ane frit, washed with petroleum ether (3 X 15 mL), and dried in vacuo. The yield is 4.25 g (90%), mp 210 °C (decomp.). 

Bis(benzonitrile)dichloroplatmum is a pale yellow solid that is soluble in benzene, chloroform, and dichloromethane but insoluble in water, alcohols, and diethyl ether. The IR spectrum (KBr pellet) shows a CsN stretching vibration at 2290cm , and two Pt—Q stretching vibrations at 350 and 360 cm . The NMR spectrum (CDCI3) exhibits two multiplets centered at 7.56 and 7.77 ppm. The NMR spectrum indicates that both 

Hartley, The Chemistry of Palladium and Platinum, Applied Sdenoe, New York, 1973, p. 462. 

ACETONITRILE COMPLEXES OF SELECTED TRANSITION METAL CATIONS 

Since these cationic, weakly solvated transition metal complexes are reactive towards atmospheric moisture, all manipulations should be performed using standard inert atmosphere techniques. 

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Attempts have been made to catalyze the arrangement of 3-oxaquadricyclane to oxepins with transition-metal complexes.1 32 1 35 When dimethyl 2,4-dimethyl-3-oxaquadricyclane-l,5-dicarboxylate is treated with bis(benzonitrile)dichloroplatinum(II) or dicarbonylrhodium chloride dimer, an oxepin with a substitution pattern different from that following thermolysis is obtained as the main product. Instead of dimethyl 2,7-dimethyloxepin-4,5-dicarboxylate, the product of the thermal isomerization, dimethyl 2,5-dimethyloxepin-3,4-dicarboxylate (12), is formed due to the cleavage of a C O bond. This transition metal catalyzed cleavage accounts also for the formation of a 6-hydroxyfulvene [(cyclopentadienylidene)methanol] derivative (10-15%) and a substituted phenol (2-6%) as minor products.135 The proportion of reaction products is dependent on solvent, catalyst, and temperature. 

Dichloro(l,5-cyclooctadiene)platinum(II) may be prepared from hexachloro-platinic acid,3 by heating bis(benzonitrile)dichloroplatinum(II)4 in 1,5-cyclo-... 

Bis[di-/-butylphosphano]tellurium reacted with platinum dichloride in toluene and with bis[benzonitrile]dichloroplatinum in dichloromethane to produce yellow crystals of the expected complex2. 

Preparation of the Polymer-Supported Catalyst. A solution of 0.12 mmol of bis(benzonitrile)dichloroplatinum(lI) in 10 mL of benzene was added to a refluxing suspension of an amount of polymer beads containing 0.21 mmol of diben-zophosphole ligand in 5 mL of benzene. Reflux was continued for 40 hours under argon. The mixture was filtered in a glove bag, washed with 10 mL of dichloro-methane and 10 mL of benzene, and dried under reduced pressure to afford the polymer-supported catalyst I in 98.6% yield solid state P NMR (CP/MAS)... 

Dichloro(l,S-cyclooctadiene)platmum(II) may be prepared from hexa-chloroplatinic acid, or by heating bis(benzonitrile)dichloroplatinum(II) in 1,5-cyclooctadiene at 145°C for 5 min, or from potassium tetra chloroplatinate(2-). The complex [PtCl2(CgHi2)] has a very low solubility in the reaction mixture and must be finely ground to ensure complete reaction. The olefins 1,5-cyclooctadiene, bicyclo[2.2.1]hept-2-ene (2-norbomeneX and 1,3,5,7-cyclooctatetraene and all solvents should be dried and freshly distilled under nitrogen. In particular, peroxide-firee diethyl ether is first dried over sodium wire and then distilled under nitrogen from sodium-benzophenone. 

Dichloropalladium and dichloroplatinum complexes containing weakly bound ligands represent convenient starting materials for the synthesis of a wide range of compounds of these two metals. The bis(acetonitrile) and bis(benzonitrile) species are commonly employed since they are easily prepared, the benzonitrile complexes having greater solubility in common organic solvents. 

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