Chiral Cu(II)-catalyzed enantioselective β-borylation of α,β-unsaturated nitriles in water
نویسندگان
چکیده
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. Both solid and liquid substrates were suitable despite being insoluble in water.
منابع مشابه
Cu(II)-catalyzed asymmetric boron conjugate addition to α,β-unsaturated imines in water.
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.
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