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Organocatalyzed asymmetric Michael reaction of ?-aryl-?-ketophosphonates and nitroalkenes.

ABSTRACT: The first enantioselective Michael reaction of ?-aryl-?-ketophosphonates and nitroalkenes has been brealized by using a new bifunctional Takemoto-type thiourea catalyst. The primary Michael adducts obtained were converted in situ to the corresponding amides through the aminolysis. High yields, excellent diastereoselectivities (>95:5 dr), and good enantioselectivities (up to 81% ee) have been achieved for the corresponding ? ,?-disubstituted ?-nitroamides. This reaction againdemon strated that ?-ketophosphonates are interesting pronucleophiles that can be used as amide surrogates in organocatalyzed reactions.

SUBMITTER: Guang J

PROVIDER: S-EPMC3810965 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Organocatalyzed asymmetric Michael reaction of β-aryl-α-ketophosphonates and nitroalkenes.

Guang Jie J Zhao John Cong-Gui JC

Tetrahedron letters 20131001 42

The first enantioselective Michael reaction of β-aryl-α-ketophosphonates and nitroalkenes has been brealized by using a new bifunctional Takemoto-type thiourea catalyst. The primary Michael adducts obtained were converted in situ to the corresponding amides through the aminolysis. High yields, excellent diastereoselectivities (>95:5 dr), and good enantioselectivities (up to 81% ee) have been achieved for the corresponding α ,β-disubstituted γ-nitroamides. This reaction againdemon strated that α- ...[more]

PMID: 24187390

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