Addition of Carbon Nucleophiles to Tricarbonylchromium Complexes of 1,2-Dihydrocyclobutabenzene, Indane, 1,2,3,4-Tetrahydronaphtbalene and<i>ortho</i>-Xylene
作者:E. Peter Kündig、Chantal Grivet、Eric Wenger、Gerald Bérnardinelli、Alan F. Williams
DOI:10.1002/hlca.19910740836
日期:1991.12.11
of products. In several cases, the mixtures of the intermediate anionic cyclohexadienyl complexes can be equilibrated to give, after oxidation, β-substituted derivatives of 1,2,3,4-tetrahydronaphthalene and ortho-xylene selectively. EHMO calculations were carried out, and they rationalize the observed α-regioselectivity of nucleophilic addition under kinetic control, The X-ray structures of 1 and 4
3-取代的1,2-二氢环丁苯(双环[4. 2. 0]八-1,3,5-三烯)很容易从[Cr(CO)3(1,2-二氢环丁苯)](1)中通过两步序列,涉及亲核试剂的添加和中间体阴离子环己二烯基复合物的氧化。使用的亲核试剂包括LiCMe 2 CN(A),LiCH 2 CN(B),LiC(Me)(OR)CN(C),(D),(E),LiCMe 2 CO 2 Me(F)和LiCH 2 CO 2(t-Bu)(G)。[Cr(CO)3(茚满)](2)也具有高度区域选择性反应,产生α-取代,而[Cr(CO)3(四氢萘)](3)和[Cr(CO)3(邻二甲苯)](4)得到产物的混合物。在几种情况下,可以平衡中间体阴离子环己二烯基络合物的混合物,以在氧化后选择性地得到1,2,3,4-四氢萘和邻二甲苯的β-取代衍生物。进行了EHMO计算,合理化了动力学控制下亲核加成反应的α-区域选择性。报道了1和4的X射线结构,两种化