Tetrachlorobis tetrahydrofuran hafnium IV , HfCl4 thf

The product is a white, crystalline solid which is air sensitive. It melts at 187°, and the infrared spectrum contains a sharp peak of medium intensity at 990 cm and a strong, broad peak at 820 cm.  

A 500-mL, single-neck, round-bottom flask equipped with a reflux condenser and magnetic stirring bar is charged with 200 mL anhydrous tetrahydrofuran and 10.0 g (65mmole) titanium trichloride. The solution is heated to reflux for 22 hours, then allowed to cool to room temperature. The resulting pale-blue crystals are collected on a medium fritted funnel and washed with 50 mL dry pentane. The pentane wash plus another 50 mL dry pentane are added to the mother liquor to give a second crop of pale-blue soUds. The total yield is 21.96 g (91.4%). 

The product is a pale-blue, air-sensitive, crystalline solid. It slowly changes color but does not melt below 250°. Its infrared spectrum contains a strong, sharp peak at 1010 cm and a strong, broad peak at 850 cm.  

A 125-mL Erlenmeyer flask equipped with a magnetic stirring bar is charged with 1.6 g aluminum powder and 50 mL dry acetonitrile. To this suspension is added with stirring 4.8 g (18mmole) niobium tetrachloride. After stirring under 

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C. TETRACHLOROBIS(TETRAHYDROFURAN)HAFNIUM(IV), HfCl4(thf)2 HfCl4 + 20C4H8------------------- HfCl4(OC4H8)2... 

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