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Stereoselective Intramolecular Cyclopropanation of ?-Diazoacetates via Co(II)-Based Metalloradical Catalysis.

ABSTRACT: Co(II) complexes of D2-symmetric chiral porphyrins have been proven to be effective metalloradical catalysts for the asymmetric intramolecular cyclopropanation of allyl ?-diazoacetates. 4-(Dimethylamino)pyridine (DMAP), through positive trans effect, plays an important role in the enhancement of the asymmetric induction for the intramolecular cyclopropanation process. This metalloradical catalytic system is suitable for cyclopropanation of allyl ?-diazoacetates with varied functional groups and substitution patterns, producing bicyclic products with complete diastereocontrol and good enantiocontrol.

SUBMITTER: Ruppel JV

PROVIDER: S-EPMC4043383 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Stereoselective Intramolecular Cyclopropanation of α-Diazoacetates via Co(II)-Based Metalloradical Catalysis.

Ruppel Joshua V JV Cui Xin X Xu Xue X Zhang X Peter XP

Organic chemistry frontiers : an international journal of organic chemistry 20140701 5

Co(II) complexes of D2-symmetric chiral porphyrins have been proven to be effective metalloradical catalysts for the asymmetric intramolecular cyclopropanation of allyl α-diazoacetates. 4-(Dimethylamino)pyridine (DMAP), through positive trans effect, plays an important role in the enhancement of the asymmetric induction for the intramolecular cyclopropanation process. This metalloradical catalytic system is suitable for cyclopropanation of allyl α-diazoacetates with vari ...[more]

PMID: 24910778

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