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Guide to Enantioselective Dirhodium(II)-Catalyzed Cyclopropanation with Aryldiazoacetates.

ABSTRACT: Catalytic enantioselective methods for the generation of cyclopropanes has been of longstanding pharmaceutical interest. Chiral dirhodium(II) catalysts prove to be an effective means for the generation of diverse cyclopropane libraries. Rh2(R-DOSP)4 is generaally the most effective catalyst for asymmetric intermolecular cyclopropanation of methyl aryldiazoacetates with styrene. Rh2(S-PTAD)4 provides high levels of enantioinduction with ortho-substituted aryldiazoacetates. The less-established Rh2(R-BNP)4 plays a complementary role to Rh2(R-DOSP)4 and Rh2(S-PTAD)4 in catalyzing highly enantioselective cyclopropanation of 3- methoxy-substituted aryldiazoacetates. Substitution on the styrene has only moderate influence on the asymmetric induction of the cyclopropanation.

SUBMITTER: Chepiga KM

PROVIDER: S-EPMC3834613 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Guide to Enantioselective Dirhodium(II)-Catalyzed Cyclopropanation with Aryldiazoacetates.

Chepiga Kathryn M KM Qin Changming C Alford Joshua S JS Chennamadhavuni Spandan S Gregg Timothy M TM Olson Jeremy P JP Davies Huw M L HM

Tetrahedron 20130701 27-28

Catalytic enantioselective methods for the generation of cyclopropanes has been of longstanding pharmaceutical interest. Chiral dirhodium(II) catalysts prove to be an effective means for the generation of diverse cyclopropane libraries. Rh2(R-DOSP)4 is generaally the most effective catalyst for asymmetric intermolecular cyclopropanation of methyl aryldiazoacetates with styrene. Rh2(S-PTAD)4 provides high levels of enantioinduction with <i ...[more]

PMID: 24273349

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