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Asymmetric Conjugate Addition of ?,?-Disubstituted Aldehydes to Nitroalkenes Organocatalyzed by Chiral Monosalicylamides from trans-Cyclohexane-1,2-Diamines.

ABSTRACT: Primary amine-salicylamides derived from chiral trans-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugate addition of ?,?-disubstituted aldehydes to arylated and heteroarylated nitroalkenes. The reaction is performed in the presence of 4-dimethylaminopyridine as an additive in dichloromethane as a solvent at room temperature. The corresponding enantioenriched ?-nitroaldehydes are obtained with enantioselectivities up to 95%. Theoretical calculations are used to justify the reasons of the stereoinduction.

SUBMITTER: Martinez-Guillen JR

PROVIDER: S-EPMC6017890 | biostudies-other | 2018 Jan

REPOSITORIES: biostudies-other

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Asymmetric Conjugate Addition of α,α-Disubstituted Aldehydes to Nitroalkenes Organocatalyzed by Chiral Monosalicylamides from trans-Cyclohexane-1,2-Diamines.

Martínez-Guillén José R JR Flores-Ferrándiz Jesús J Gómez Cecilia C Gómez-Bengoa Enrique E Chinchilla Rafael R Chinchilla Rafael R

Molecules (Basel, Switzerland) 20180111 1

Primary amine-salicylamides derived from chiral <i>trans</i>-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugate addition of α,α-disubstituted aldehydes to arylated and heteroarylated nitroalkenes. The reaction is performed in the presence of 4-dimethylaminopyridine as an additive in dichloromethane as a solvent at room temperature. The corresponding enantioenriched γ-nitroaldehydes are obtained with enantioselectivities up to 95%. Theoretical calculations are ...[more]

PMID: 29324713

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