Benzyl Cation Stabilized by Metal Complexation. Relative Stability of Coordinated Methylene Arenium, π-Benzylic, and σ-Benzylic Structures
作者： Elena Poverenov , Irena Efremenko , Gregory Leitus , Jan M. L. Martin , David Milstein
DOI: 10.1021/OM400523F
关键词:
摘要: Benzyl cations are highly reactive compounds involved as intermediates in various chemical and biochemical processes. In this work metal coordination was utilized to stabilize different coordinated modes of benzyl cations, including methylene arenium (MA), π-benzyl, σ-benzyl complexes. Two bidentate ligand frameworks, diphenylphosphinoethane (dppe) di-tert-butylphosphinopropane (dtpp), were studied. η2-Coordination Pd(II) allows for the characterization studies reactivity otherwise unobserved species under ambient conditions. The relative stability electronic structure three forms molecule, η2-MA, η1-σ-benzylic, η3- π-benzylic, investigated experimentally computationally. MA π-benzylic structures preferred absence counteranions, while dtpp bulky contributes stabilization form. Counteranions have a significant influence on stability. ...
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