Asymmetric synthesis of functionalized cyclohexanes bearing five stereocenters via a one-pot organocatalytic Michael–Michael–1,2-addition sequence
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چکیده
منابع مشابه
Organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence for the stereocontrolled formation of six consecutive stereocenters.
An unprecedented stereoselective organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence between β-dicarbonyl compounds, β-nitroalkenes and 4-nitro-5-styrylisoxazoles sequentially catalyzed by low loading of a squaramide catalyst and an achiral base has been developed. The protocol opens an efficient entry to isoxazole bearing cyclohexanes with six consecutive stereogenic centers including one ...
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متن کاملAsymmetric synthesis of functionalized cyclohexanes bearing five stereocenters via a one-pot organocatalytic Michael–Michael–1,2-addition sequence† †Electronic supplementary information (ESI) available. CCDC 990847. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4cc01885k Click here for additional data file. Click here for additional data file.
A highly stereoselective one-pot procedure involving an enantioselective Michael addition promoted by low loading of an amino-squaramide catalyst followed by an achiral base catalyzed domino Michael-Knoevenagel-type 1,2-addition sequence provides efficient access to fully substituted cyclohexanes bearing five contiguous stereogenic centers in good yields (68-86%) and excellent stereoselectiviti...
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A highly enantioselective organocatalytic Wolff rearrangement–amidation–Michael– hemiaminalization stepwise reaction is described involving a cyclic 2-diazo-1,3-diketone, primary amine and α,β-unsaturated aldehyde. Product stereocontrol can be achieved by adjusting the sequence of steps in this one-pot multicomponent reaction. This approach was used to synthesize various optically active spiroc...
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ژورنال
عنوان ژورنال: Chem. Commun.
سال: 2014
ISSN: 1359-7345,1364-548X
DOI: 10.1039/c4cc01885k