Allylpalladium Complexes with <i>P</i>-Stereogenic Monodentate Phosphines. Application in the Asymmetric Hydrovinylation of Styrene
作者:Arnald Grabulosa、Guillermo Muller、Juan I. Ordinas、Antonio Mezzetti、Miguel Ángel Maestro、Mercè Font-Bardia、Xavier Solans
DOI:10.1021/om050421v
日期:2005.10.1
complexes [PdCl(ally)P*]. The reaction carried out with deuterated styrene shows the clean C−H addition to the vinyl double bond of stryrene and confirms the irreversible nature of the insertion of styrene in the palladium hydride intermediate. The hydrovinylation reaction using substituted styrene with a potentially secondary coordination atom occurs only when the substitution is in the phenyl ring and
一组P-立体异构单齿膦S -PPhRR'(R = 1-萘基,9-菲基或邻-联苯基,R'= CH 3-,i -C 3 H 8-和Ph 3 SiCH 2-)通过在由(-)-麻黄碱和双(N,N-二乙氨基)苯基膦获得的恶杂磷硼烷硼烷上进行连续取代反应,制备了α-己内酰胺。与双核烯丙基化合物[Pd(μ-Cl)(烯丙基)] 2的反应产生中性[PdCl(烯丙基)P *]配合物。当烯丙基= 2-CH 3 -C 3 H 4(5),由于钯原子周围的R-或S-几何形状,溶液中出现了两种异构体。膦的鉴别作用很小,并且对PPh(o -Ph 2)(CH 2 SiPh 3)观察到最大异构体比率。通过X射线衍射确定的两个配合物的分子结构具有P * = PPh(o -Ph 2)(i -Pr)和PPh(o -Ph 2)(OMe),表明烯丙基部分的非对称配位非常相似。磷原子的反式影响更大。当烯丙基= 1-C 6 H 5时-C 3