Diels-Alder adducts of 1-benzenesulfonylindole-2-acrylates and 1-(alkoxycarbonyl)-1,2-dihydropyridines. Intermediates for synthesis of iboga alkaloid analogs
sensitive reagents restricts the applicability in synthetic laboratories. Herein, we report the synthesis of a broad variety of N-substituted 1,4- and 1,2-dihydropyridines by very mild and selective reduction with amine borane for the first time.
A novel chiral oxazolidine organocatalyst for the synthesis of an oseltamivir intermediate using a highly enantioselective Diels–Alder reaction of 1,2-dihydropyridine
Enantioselective DielsâAlder reactions of 1,2-dihydropyridines with acroleins using a novel chiral oxazolidine organocatalyst afforded chiral isoquinuclidines that is an efficient synthetic intermediate of oseltamivir, with fairly good chemical yield and excellent enantioselectivity (90%, up to >99% ee).
ISOQUINUCLIDINE DERIVATIVE AND METHOD FOR PRODUCING 1-CYCLOHEXENE-1-CARBOXYLIC ACID DERIVATIVE BY USING THE SAME
申请人:The University of Tokyo
公开号:EP2050752A1
公开(公告)日:2009-04-22
The present invention provides an isoquinuclidine derivative which can be used to easily synthesize oseltamivir or an analog thereof. In particular, the present invention provides an isoquinuclidine derivative represented by the following formula (1) or an enantiomer thereof:
wherein in the formula (1), A represents a protective group for the nitrogen atom; R1 to R1 each independently represent an alkyl group which may have a substituent, an aryl group which may have a substituent, or a hydrogen atom; and X represents a halogen atom.
BBr3-chiral phosphoric acid complexes are highly effective and practical Lewis acid-assisted Brønsted acid (LBA) catalysts for promoting the enantioselective Diels-Alder (DA) reaction of α-substituted acroleins and α-CF3 acrylate. In particular, the DA reaction of α-substituted acroleins with 1,2-dihydropyridines gave the corresponding optically active isoquinuclidines with high enantioselectivities
The Role of Achiral Pyrazolidinone Templates in Enantioselective Diels−Alder Reactions: Scope, Limitations, and Conformational Insights
作者:Mukund P. Sibi、Levi M. Stanley、Xiaoping Nie、Lakshmanan Venkatraman、Mei Liu、Craig P. Jasperse
DOI:10.1021/ja066425o
日期:2007.1.1
were also observed in reactions of 7d with chiralLewis acids derived from relatively small chiralligands, suggesting the pyrazolidinone templates are capable of relaying stereochemical information from the ligand to the reaction center. Lewis acids capable of adapting square planar geometries, such as Cu(OTf)2, Cu(ClO4)2, and Pd(ClO4)2, were found to be particularly effective at providing high selectivities