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On the stereochemical course of palladium-catalyzed cross-coupling of allylic silanolate salts with aromatic bromides.

ABSTRACT: The stereochemical course of palladium-catalyzed cross-coupling reactions of an enantioenriched, alpha-substituted, allylic silanolate salt with aromatic bromides has been investigated. The allylic silanolate salt was prepared in high geometrical (Z/E, 94:6) and high enantiomeric (94:6 er) purity by a copper-catalyzed S(N)2' reaction of a resolved allylic carbamate. Eight different aromatic bromides underwent cross-coupling with excellent constitutional site-selectivity and excellent stereospecificity. Stereochemical correlation established that the transmetalation event proceeds through a syn S(E)' mechanism which is interpreted in terms of an intramolecular delivery of the arylpalladium electrophile through a key intermediate that contains a discrete Si-O-Pd linkage.

SUBMITTER: Denmark SE

PROVIDER: S-EPMC2836786 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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On the stereochemical course of palladium-catalyzed cross-coupling of allylic silanolate salts with aromatic bromides.

Denmark Scott E SE Werner Nathan S NS

Journal of the American Chemical Society 20100301 10

The stereochemical course of palladium-catalyzed cross-coupling reactions of an enantioenriched, alpha-substituted, allylic silanolate salt with aromatic bromides has been investigated. The allylic silanolate salt was prepared in high geometrical (Z/E, 94:6) and high enantiomeric (94:6 er) purity by a copper-catalyzed S(N)2' reaction of a resolved allylic carbamate. Eight different aromatic bromides underwent cross-coupling with excellent constitutional site-selectivity and excellent stereospeci ...[more]

PMID: 20163185

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