Catalytic asymmetric conjugate addition of Grignard reagents to chromones
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چکیده
منابع مشابه
Catalytic asymmetric conjugate addition of Grignard reagents to chromones.
A highly regio- and enantioselective copper catalysed direct conjugate addition of Grignard reagents to chromones has been developed taking advantage of the reduced reactivity of the resulting magnesium enolates. This methodology tolerates a broad scope of alkyl Grignards including secondary alkyl magnesium reagents as well as functionalised chromones.
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متن کاملAsymmetric amplification in the catalytic enantioselective 1,2-addition of Grignard reagents to enones.
Large asymmetric amplification originating from solubility differences between the enantiopure and the racemic catalyst is observed in the addition of Grignard reagents to enones. This behaviour is not reaction or catalyst specific and is observed for metal complexes of a variety of chiral diphosphine ligands, extensively used in asymmetric catalysis.
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ژورنال
عنوان ژورنال: Chemical Communications
سال: 2013
ISSN: 1359-7345,1364-548X
DOI: 10.1039/c3cc43105c