π-cyclopentadienyl-π-cycloheptatrienyl derivatives of chromium and molybdenum

✍ Scribed by R.B. King; M.B. Bisnette

• Publisher: Elsevier Science
• Year: 1963
• Tongue: French
• Weight: 225 KB
• Volume: 4
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)90790-7

✦ Synopsis

The recent report by Fischer and Breitschaft' of a -o-step synthesis of C&$rC+_r from the difficultly accessible c~H&~c&~ prompts us to report a much more convenient one-step synthesis of C5H5CrC7H7 from the readily available anhydrous chromium (III) chloride. 2 A mixture of enhydrous chromium (III) chloride (0.1 mole), cyclopentadiene (0.12 mole), and cycloheptatriene (0.25 mole) was treated with P solution of isopropylmagnesium bromide (0.5 mole) in diethyl ether at -78'. The reaction mixture was allowed to warm slowly to room temperature and stirred for several hours at room temperature. It was then decomposed by the gradual addition of methanol at -78'. From the resulting very airsensitive green-brown solution, dark green crystals of C5H&rC7H7, m.p. -225" (lit.'. m.p. -230'). could be isolated by evaporation at 20 w and sublimation of the residue at lOO-150'/0.1 nun. The crude product was purified further by washing with pentane and resublimetion at 80-100"/0.1 0111.