Bis triphenylphosphoranylidene sulfamide

Checked by Sherman Thomas, George Grimm, and Doyle Britton  

Magnesium turnings (3.64 g. 0.15 mol), previously treated with a small crystal of iodine, are placed in a dry 500-ml. three-necked flask fitted with a reflux condenser with a phosphorus(V) oxide drying tube on top, a magnetic stirring bar, and a 250-ml. pressure-equalizing funnel. 

Both compounds are white, crystalline, and nonhygro-scopic. They are insoluble in cold or boiling water, -hep-tane, petroleum ether, and ethyl ether somewhat more soluble in ethanol, benzene, and carbon tetrachloride and soluble in acetone and chloroform. Each shows a strong absorption band in the 1255 to 1300 cm. i region that is 

Cycloheptatrienemolybdenum tricarbonyl has been prepared by refluxing cycloheptatriene with molybdenum hexacarbonyl in benzene. It is a convenient starting material for the preparation of trisubstituted molybdenum carbonyls and of tropyliummolybdenum carbonyl salts.  

The product forms as dark red hexagonal prisms or, when finely divided, as orange-red needles. It decomposes at 95° and sublimes rapidly at 85° in vacuo. It is very soluble in alcohol, acetone, benzene, chloroform, and dichlorometh-ane, moderately soluble in ether, and only sparingly soluble in -hexane. It is scarcely soluble in n-octane and decomposes in carbon tetrachloride. The solutions are sensitive to air and light, and the solid is best stored in the dark. 

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