Highly linear selective cobalt-catalyzed addition of aryl Imines to styrenes : reversing intrinsic regioselectivity by ligand elaboration

• Main Authors: Xu, Wengang, Yoshikai, Naohiko
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2015
• Subjects: DRNTU::Science::Chemistry
• Online Access: https://hdl.handle.net/10356/103943; http://hdl.handle.net/10220/24637
• Institution: Nanyang Technological University

Highly linear selective, imine-directed hydroarylation of styrene has been achieved with cobalt-based catalytic systems featuring bis(2,4-dimethoxyphenyl)(phenyl)phosphine and either 2-methoxypyridine or DBU as a ligand and a Lewis base additive, respectively, thus affording a variety of 1,2-diarylethanes (bibenzyls) in good yields under mild reaction conditions. The triarylphosphine controls the regioselectivity, while the Lewis base significantly accelerates the reaction. Ligand screening and deuterium-labeling studies provide implications about the roles of the ligand and the Lewis base in the crucial C[BOND]C reductive elimination step.