Highly linear selective cobalt-catalyzed addition of aryl Imines to styrenes : reversing intrinsic regioselectivity by ligand elaboration
Date of Issue2014
School of Physical and Mathematical Sciences
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.
Angewandte chemie international edition
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