Molybdenum, tetrachlorobis

Tetrahydrofuran (THF) (80 mL, freshly distilled from sodium benzophenone ketyl) is added from a 250-mL Schienk flask to bis(acetonitrile)tetrachloro-molybdenum(IV) (20 g, 0.052 mole) in a 250-mL Schienk flask and the mixture is stirred rapidly for 2 hours to give a yellow suspension of tetrachlorobis-(tetrahydrofuran)molybdenum(IV). The complex is filtered through a Schienk filter, washed with THF (20 mL), and dried in vacuo (10 2 torr) at room temperature. The product is obtained as a microcrystalline orange-yellow powder in yields of 15-17 g, 63-71%. The product is not analytically pure. Anal. Calcd. for CbH1602C14Mo C, 25.1 H, 4.9. Found C, 26.5 H, 4.2. However, it is sufficiently pure for subsequent reactions. 

The reaction is carried out in an inert atmosphere using rigorously anhydrous solvent. Tetrachlorobis(propionitrile)molybdenum(IV)3 (1.7 g., 5 mmoles) is added to 20 ml. of dichloromethane containing 2.2 g. (11 mmoles) of methyldiphenylphosphine. The solid dissolves immediately, and within 1 minute, dark-red crystals begin to form. After 20 minutes the product is collected by filtration, washed twice with 8 ml. of dichloromethane, and dried under vacuum. The yield is approximately 2.5 g. (77%). The product, when pulverized, is dark orange. Anal. Calcd. for C26H26P2Cl4Mo C, 48.9 H, 4.11. Found C, 48.8 H, 4.10. 

The reaction is carried put in an atmosphere of scrupulously dry, air-free argon or helium. Tetrachlorobis(methyldiphenyl-phosphine)molybdenum(IV) (1.6 g., 2.5 mmoles) is added slowly with stirring to 30 ml. of ethanol containing 1.2 g. (6 mmoles) of methyldiphenylphosphine and 0.8 g. (21 mmoles) of sodium tetra-... 

Tetrachlorobis(tetrahydrofuran)molybdenum(IV), 5.0 g, is suspended in 60 mL of tetrahydrofuran and stirred with 10 g of coarse tin powder, 20 mesh, at room temperature for 20 min. The solution is filtered, and any [MoCl3(thf)3] product on the sinter is freed from tin by washing through with 20 mL of dry dichloromethane. The solution is evaporated at 10 torr to —30 mL, and the complex is removed by filtration as a pale orange ciystalline material. Yield 3.4 g (62%). The complex is stored under dry argon in a freezer and in the dark. Care should be taken, since the product is extremely moisture-sensitive. 

C52H48CI2M0P4 CH2Cl2f trans-Dichlorobis(1,2-bis(diphenylphos-phino)ethano)molybdenum(II) dichloromethane solvate, 46B, 1298 C52H4eCli CoP4Sn, Chlorobis( 1,2-bis(diphenylphosphino)ethane)cobalt-(II) trichlorostannatedi), 38B, 1051 39B, 871 C5 2H4 8Cl4P4Re2 f Tetrachlorobis(1,2-bis(diphenylphosphino)ethane)dir-henium, 44B, 1084... 

Ce 5H9oCl8MoNi,P8Re2, Di-M dini trogen-tetrachlorobis (chlorotetrakis-(dimethylphenylphosphine)rhenio)molybdenum dichloromethane solvate, 42B, 998... 

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