Synthesis, stereochemistry, bonding and fluxionality of 2-(inden-3-yl)phenols and their cyclopentadienyl titanium derivatives
作者:Luke E. Turner、Matthew G. Thorn、R. D. Swartz II、Robert W. Chesnut、Phillip E. Fanwick、Ian P. Rothwell
DOI:10.1039/b310415j
日期:——
for 1,2-dimethyl derivative 9. Hence, it appears that replacement of the phenolic proton by the much bulkier [CpTiCl2] unit destabilizes the (aS,R) and (aR,S) forms in solution. Attempted de-protonation of the inden-3-yl ring in 7 by treatment with n-BuLi or MeLi did not lead to the formation of chelate rings. Instead formation of a Ti(III) dinuclear compound 11 and dimethyl derivative 12 occurred. The
酚试剂2-(茚满-3-基)-4,6-二叔丁基苯酚(1)及其2-甲基(2),1,2-二甲基(3),2,4,7-三甲基已获得(4)和1,2,4,7-四甲基(5)衍生物。的固态结构2,3和4已经通过X射线衍射和扭转角的57,61和79(乙烯基和苯氧基环之间)确定°测量。(a R)和(a S)形式的配体均以固态存在。解决方案1 H NMR光谱表明,对于下列条件,围绕茚基-苯氧基键的旋转很容易类似于图1,但是2-甲基取代基的引入导致在NMR时间尺度上旋转受限。在分析的3的晶体中,仅存在(a S,S)和(a R,R)形式,其中1-甲基指向OH基。在3和5的1 H和13 C NMR光谱中,有两个相等强度的信号集。因此,两个非对映异构形式存在于等浓度在溶液中和两个尖锐ö ħ单峰被观察到3中,即使在130℃ p二甲苯-d 10。在吡啶存在下,酚1–4与[CpTiCl 3 ]的反应先前已经生成了相应的单芳基氧