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Synthesis of non-racemic 4-nitro-2-sulfonylbutan-1-ones via Ni(II)-catalyzed asymmetric Michael reaction of ?-ketosulfones.

ABSTRACT: Functionally substituted sulfones with stereogenic centers are valuable reagents in organic synthesis and key motifs in some bioactive compounds. The asymmetric Michael addition of ?-ketosulfones to conjugated nitroalkenes in the presence of Ni(II) complexes with various chiral vicinal diamines was studied. This reaction provides convenient access to non-racemic 4-nitro-2-sulfonylbutan-1-ones with two stereocenters with high yield and excellent enantioselectivity (up to 99%). It has been established that the catalytic Michael reaction itself was carried out with high diastereoselectivity, but the Michael adducts may epimerize at the C-2 position at a significant rate. Conditions for the preparation of individual diastereomers were found.

SUBMITTER: Reznikov AN

PROVIDER: S-EPMC6604683 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Synthesis of non-racemic 4-nitro-2-sulfonylbutan-1-ones via Ni(II)-catalyzed asymmetric Michael reaction of β-ketosulfones.

Reznikov Alexander N AN Sibiryakova Anastasiya E AE Baimuratov Marat R MR Golovin Eugene V EV Rybakov Victor B VB Klimochkin Yuri N YN

Beilstein journal of organic chemistry 20190612

Functionally substituted sulfones with stereogenic centers are valuable reagents in organic synthesis and key motifs in some bioactive compounds. The asymmetric Michael addition of β-ketosulfones to conjugated nitroalkenes in the presence of Ni(II) complexes with various chiral vicinal diamines was studied. This reaction provides convenient access to non-racemic 4-nitro-2-sulfonylbutan-1-ones with two stereocenters with high yield and excellent enantioselectivity (up to 99%). It has been establi ...[more]

PMID: 31293677

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