Allenes as carbon nucleophiles in intramolecular attack on (π-1,3-diene)palladium complexes:: Evidence for trans carbopalladation of the 1,3-diene
Allenes as carbon nucleophiles in intramolecular attack on (π-1,3-diene)palladium complexes:: Evidence for trans carbopalladation of the 1,3-diene
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DOI：
10.1002/chem.200305056
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发表时间：
2003-07-21
影响因子：
4.3
通讯作者：
Bäckvall, JE
中科院分区：
文献类型：
--
作者：
Dorange, I;Löfstedt, J;Bäckvall, JE
联二烯取代的环己二烯和环庚二烯与[PdCl_2（PhCN）（2）]反应，得到了eta（3）-（1，2，3）-环己烯基和eta（3）-（1，2，3）-环庚烯基钯配合物。分别其中在丙二烯和1，3-二烯之间形成C-C键。通过NMR光谱分析（π-烯丙基）钯络合物。使用报告配体，表明C-C键的形成是通过反式碳钯化反应发生的，该反应涉及联二烯的中间碳原子对（π-二烯）钯（n）络合物的亲核攻击。的（π-烯丙基）钯配合物的立体化学证实了由苯醌诱导的立体选择性转化为烯丙基乙酸酯。
Reaction of allene-substituted cyclohexa- and cyclohepta-1,3-dienes with [PdCl2(PhCN)(2)] gave eta(3)-( 1,2,3)-cyclohexenyl- and eta(3)-(1,2,3)-cycloheptenylpalladium complexes. respectively. in which C-C bond formation between the allene and the 1.3-diene has occurred. Analysis of the (pi-allyl)palladium complexes by NMR spectroscopy. using reporter ligands, shows that the C-C bond formation has occurred by a trans carbopalladation involving nucleophilic attack by the middle carbon atom of the allene on a (pi-diene)palladium(n) complex. The stereochemistry of the (pi-allyl)palladium complexes was confirmed by benzoquinone-induced stereoselective transformations to allylic acetates.