Pentacarbonyl methoxyphenylmethylene tungsten

Pentacarbonyl(methoxyphenylmethylene)tungsten(0), [Pentacarbonyl[methoxy(phenyl)carbene] tungsten(O)] 

The subsequent separation is performed under a nitrogen atmosphere with deoxygenated hexane. Approximately 2 g of carbene complex can be purified at one time on this column. After the portion of the eluant containing the deep-red carbene complex is isolated, this solution is reduced under vacuum to a volume of 10 mL and crystallization is induced by cooling to -15°. Anal. Calcd. for C13H806W C, 35.16 H, 1.82 O, 21.62 W, 41.40. Found C, 35.12 H, 1.67 0, 21.50 W, 41.60. 

The red thermally unstable crystals are soluble in organic solvents. Since the complex is extremely sensitive to nucleophiles, traces of moisture and alcohols have to be removed from all solvents before use. The complex must be stored under nitrogen below -20°. IR Vqq at 2070 (m), 1952 (vs, br), 1942 (vs, br) cm 1 in pentane, H NMR (TMS, C6D6, 60 MHz) tsjch3 at 9.93 ppm (singlet), tCHj at 8.11 ppm (singlet), rCtH at 2.68 ppm (doublet) + 3.08 ppm (doublet). 

Pentacarbonyl[ethoxy(diethylamino)methylene ] chromium(O). Pentacarbonyl [ ethoxy (diethylamino)carbene ] chromium(0)  

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