四亚甲基双(环戊二烯基)二氯化钛、锆的合成和~1H NMR谱

SYTHESIS AND ~1H NMR OF TETRAMETHYLENE-BRIDGED TITANIUM AND ZIRCONIUM DERIVATIVES

文献中已报道了亚甲基桥联双环戊二烯基二氯化钛、锆、（CH2）n（C5H4）2MCl2（M=Ti、Zr;n=1,2,3）的合成和1HNMR谱。我们按如下反应合成了四亚甲基双（环戊二烯基）二氯化钛、锆化合物。

In the present paper, we are reporting the novel tetramethylene-bridged titanocene and zirconocene dichloride. Tetramethylene dicyclopentadienide disodium reacted with tetrachloride titanium and zirconium separately at room temperature in tetrahydrofuran to prepare tetramethylene-bridged titanocene, (CH2 )4 (C5H4)2TiCl2yield 21.4%, m.p.104-106℃. δH: 6.37, 6.24(8H, m, 2C5H4), 2.74(4H, t, 2α-CH2-), 1.19(4H, m, 2β-CH2-) and tetramethylene-bridged zirconocene dichloride, (CH2 )4(C5H4 )2ZrCl2, yield 24.5% , m.p.77-79℃.δH: 6.27, 6.23(8H, m, 2C5H4), 2.68(4H, t, 2α-CH2-), 1.19(4H, m, 2β -CH2-). In the methylene-bridged titanocene dichlorides, (CH2 )n(C5H4 )2TiCl2(n= 1,2,3,4), since the C(1)-C(1') distance for two aromatic cyclopentadienyl ring increases as the number for methylene-bridged increases and a shift of π-electron density away from the bridgehead towar to distal ring position, the Ha chemical shifts move to lower-field, and Hb chemical shifts move to high-field according to the order of decreasing of number for methylene-bridged. The proton chemical shifts for tetramethylene-bridged titanocene dichloride and bis(ethylcyclopentadicnyl) titanium dichloride are similar. The results show that the molecular structure of tetramethylene-bridged titanocene dichloride bears analogy to bis(ethylcyclopentadienyl)-titanium dichloride.