Synthesis and Application of Diphenyl Sulfide Linked Bis(imidazoline) Ligands: Dramatic Electronic Effect of Ligands on Catalytic Behavior
作者:Xian Du、Han Liu、Da-Ming Du
DOI:10.1002/ejoc.201001347
日期:2011.2
Diphenyl sulfide linked bis(imidazoline) ligands with electron-withdrawing N-Ts substitution and electron-donating N-alkyl or N-H substitutions were synthesized through different routes. The electronic effects of the ligands were tuned rationally, and dramatic variation in their catalytic behavior was observed. N-Alkyl and N-H ligands demonstrated much higher catalytic activity and improved enantioselectivity
通过不同的途径合成了具有吸电子N-Ts取代和供电子N-烷基或NH取代的二苯硫醚连接的双(咪唑啉)配体。配体的电子效应被合理调整,并观察到其催化行为的显着变化。N-烷基和NH配体在Pd催化的不对称烯丙基烷基化反应中表现出比N-Ts配体更高的催化活性和更高的对映选择性。