Cu(II)-catalyzed asymmetric boron conjugate addition to α,β-unsaturated imines in water.
نویسندگان
چکیده
Enantioselective conjugate addition of bis(pinacolato)diboron to α,β-unsaturated imines proceeds smoothly in water in the presence of a chiral copper(II) complex consisting of Cu(OAc)2 and chiral 2,2'-bipyridine. The corresponding β-boryl imines, which were oxidized to β-hydroxy imines, further leading to γ-amino alcohols, were obtained in high yields and high enantioselectivities.
منابع مشابه
Chiral Cu(II)-catalyzed enantioselective β-borylation of α,β-unsaturated nitriles in water
The promising performance of copper(II) complexes was demonstrated for asymmetric boron conjugate addition to α,β-unsaturated nitriles in water. The catalyst system, which consisted of Cu(OAc)2 and a chiral 2,2'-bipyridine ligand, enabled β-borylation and chiral induction in water. Subsequent protonation, which was accelerated in aqueous medium, led to high activity of this asymmetric catalysis...
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 66 شماره
صفحات -
تاریخ انتشار 2014