could be isolated, and the conversion of anti-2 into syn-2 was monitored by NMR spectroscopy at 35, 50, 65, and 80 °C, affording an enthalpy of activation of ΔH⧧ = 24(1) kcal mol–1 for this equilibrium reaction. On the basis of DFT calculations, a mechanism is proposed that proceeds via consecutive η3–η1–η3 interconversions and involves η3-benzyl intermediates. In contrast, rapid equilibration was observed
[的Fel 2(THF)2 ]依次用的Li(C处理5我5)和phenylmethallyl的
钾盐(“开放
茚基”)
配体oInd我,导致半开
二茂铁[的选择性形成(η 5 -C 5我5)的Fe(η 5 -oInd我)](1)。可变温度NMR研究表明,约有一个壁垒。12 kcal mol –1用于旋转苯基。所述oInd的表观不稳定性和敏感性我在
配体1接受η 5 -η 3互允许的络合物的制备[(η 5 -C 5我5)的Fe(η 3 -oInd我)(L)](2,L = CO; 3,L = IME; 4,L = PME 3)通过分别添加
一氧化碳,1,3,4,5-四甲基
咪唑啉-2-亚烷基(IMe)和
三甲基膦。的η 3 -结合的
配体phenylmethallyl在这些复合物最初采用的反相对于苯基和甲基取代基的相对位置取向,随后抗-到-顺异构化。对于L = CO,这两种异构体可以被分离,并且转化反- 2成顺式-