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Organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence for the stereocontrolled formation of six consecutive stereocenters.

ABSTRACT: An unprecedented stereoselective organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence between ?-dicarbonyl compounds, ?-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 tetrasubstituted carbon in good yields and excellent diastereo- and enantioselectivities.

SUBMITTER: Chauhan P

PROVIDER: S-EPMC4612129 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence for the stereocontrolled formation of six consecutive stereocenters.

Chauhan Pankaj P Mahajan Suruchi S Raabe Gerhard G Enders Dieter D

Chemical communications (Cambridge, England) 20150201 12

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 tetrasubstituted carbon in good yields and excellent diastereo- and enantioselectivities. ...[more]

PMID: 25563802

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