Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
J Am Chem Soc. 2010 May 12;132(18):6276-7. doi: 10.1021/ja9102259.
The synthesis of (dppf)Pd(C(6)H(4)-p-F)[N(Ar(1))(CH(2))(3)CH horizontal lineCH(2)] complexes (3), which are thought to be intermediates in Pd-catalyzed alkene carboamination reactions, is described. These complexes undergo syn-migratory insertion of the alkene into the Pd-N bond to yield observable (dppf)palladium(aryl)(pyrrolidin-2-yl-methyl) complexes 6. Reductive elimination from 6 provides 2-benzylpyrrolidine derivatives 4. The rates of conversion of 3 to 6 (k(1)) and 6 to 4 (k(2)) were measured and are within 1 order of magnitude of each other. The syn-migratory insertion stereochemistry was confirmed through a deuterium labeling experiment. These are the first examples of syn-migratory insertions of unactivated alkenes into Pd-N bonds of well-defined complexes.
描述了(dppf)Pd(C(6)H(4)-p-F)[N(Ar(1))(CH(2))(3)CH 横线 CH(2)]配合物(3)的合成,这些配合物被认为是 Pd 催化的烯碳氨化反应中的中间体。这些配合物经历顺式迁移插入烯烃到 Pd-N 键中,生成可观察到的(dppf)钯(芳基)(吡咯烷-2-基-甲基)配合物 6。从 6 进行还原消除提供 2-苄基吡咯烷衍生物 4。3 到 6(k(1))和 6 到 4(k(2))的转化速率进行了测量,彼此在 1 个数量级内。顺式迁移插入的立体化学通过氘标记实验得到证实。这些是首例未活化烯烃顺式迁移插入到定义明确的配合物中的 Pd-N 键的例子。