Cycloadditions [4+2] d'une serie de pentamethylcyclopentadienes comportants des substituants avec unheteroatome en C-5, avec l'anhydride maleique et/ou le N-phenylmaleimide
Heteroatom-directed .pi.-facial diastereoselection in Diels-Alder cycloadditions of plane-nonsymmetric cyclopentadienes
作者:John B. Macaulay、Alex G. Fallis
DOI:10.1021/ja00159a038
日期:1990.1
Cycloadditions [4+2] d'une serie de pentamethylcyclopentadienes comportants des substituants avec un heteroatome en C-5, avec l'anhydride maleique et/ou le N-phenylmaleimide
Cycloadditions [4+2] d'une serie de pentamethylcyclopentadienes comportants des substituants avec unheteroatome en C-5, avec l'anhydride maleique et/ou le N-phenylmaleimide
Bent vs Linear Metallocenes Involving C<sub>5</sub>Me<sub>5</sub> vs C<sub>8</sub>H<sub>8</sub> Ligands: Synthesis, Structure, and Reactivity of the Triple-Decked (C<sub>5</sub>Me<sub>5</sub>)(THF)<i><sub>x</sub></i>Sm(C<sub>8</sub>H<sub>8</sub>)Sm(THF)<i><sub>x</sub></i>(C<sub>5</sub>Me<sub>5</sub>) (<i>x</i> = 0, 1) Complexes Including a Formal Two-Electron Oxidative Addition to a Single Lanthanide Metal Center<sup>1</sup>
作者:William J. Evans、Robert D. Clark、Mohammad A. Ansari、Joseph W. Ziller
DOI:10.1021/ja980735s
日期:1998.9.1
triple-decked organometallic sandwichcomplexes involving Sm(II) can be prepared by reacting [(C5Me4R)Sm(μ-I)(THF)2]2 with 1 equiv of K2C8H8 in toluene to form [(C5Me4R)Sm(THF)]2(μ-η8:η8-C8H8) (R = Me, 1; R = Et, 2). The diglyme ([MeOCH2CH2]2O) adduct of 1, [(C5Me5)Sm(diglyme)]2(μ-η8:η8-C8H8)}(THF)2 (3) crystallizes from THF with a bridging (C8H8)2- dianion sandwiched between two [(C5Me5)Sm(diglyme)]+
通过 [(C5Me4R)Sm(μ-I)(THF)2]2 与 1 当量的 K2C8H8 在甲苯中反应形成 [(C5Me4R) Sm(THF)]2(μ-η8:η8-C8H8) (R = Me, 1; R = Et, 2)。1 的二甘醇二甲醚 ([MeOCH2CH2]2O) 加合物 [(C5Me5)Sm(diglyme)]2(μ-η8:η8-C8H8)}(THF)2 (3) 从四氢呋喃中结晶,带有桥连 (C8H8)2 - 二价阴离子夹在两个 [(C5Me5)Sm(diglyme)]+ 阳离子之间,具有 137.6°(C5Me5 环质心)-Sm-(C8H8 环质心)角。这种弯曲的三层茂金属具有 2.91(2) A Sm-C(C5Me5) 和 2.96(5) A Sm-C(C8H8) 平均距离。1 和 2 可以在 30-50 °C 下在高真空下脱溶剂数小时,得到 [(C5Me4R)Sm]2(μ-η8:η8-C8H8)