Rhodium catalyzed enantioselective cyclization of substituted imidazoles via C–H bond activation
نویسندگان
چکیده
منابع مشابه
Desymmetrization of enone-diones via rhodium-catalyzed diastereo- and enantioselective tandem conjugate addition-aldol cyclization.
Catalytic tandem conjugate addition-enolate trapping represents an effective strategy for the design of catalytic transformations that enable formation of multiple C-C bonds. Recently, using enantioselective rhodium-catalyzed conjugate addition methodology, we developed a catalytic tandem conjugate addition-aldol cyclization of keto-enones. Here, we report related desymmetrizations and parallel...
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Chiral rhodium(I)-catalyzed highly enantioselective arylation of aliphatic N-sulfonyl aldimines with arylboronic acids has been developed. This transformation is achieved by the use of a rhodium/bis(phosphoramidite) catalyst to give enantiomerically enriched α-branched amines (up to 99 % ee). In addition, this system enables efficient synthesis of (+)-NPS R-568 and Cinacalcet which are calcimim...
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Rh(III)-catalyzed direct olefination reaction via aromatic C-H bond activation is described using tetrazole as the directing group. This reaction provides a straightforward way for the synthesis of ortho-alkenyl aryl tetrazoles. Various functional groups tolerate the reaction conditions and afford the corresponding products in moderate to excellent yields.
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ژورنال
عنوان ژورنال: Chemical Communications
سال: 2009
ISSN: 1359-7345,1364-548X
DOI: 10.1039/b902878a