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SmI2-promoted Reformatsky-type coupling reactions in exceptionally hindered contexts.

ABSTRACT: Highly substituted, very hindered enones were synthesized using a two-step procedure that utilizes a diiodosamarium-promoted Reformatsky-type coupling and dehydration using Martin sulfurane. Both alpha-chloro- and alpha-bromoketones were coupled with a variety of carbonyl nucleophiles to form the intermediate beta-hydroxyketones, occurring with excellent diastereoselectivity, favoring the syn isomer (R1=Me). This technique complements other methods and enables the preparation of enones outside of the scope of current olefination methodology.

SUBMITTER: Sparling BA

PROVIDER: S-EPMC3148185 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature

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SmI2-promoted Reformatsky-type coupling reactions in exceptionally hindered contexts.

Sparling Brian A BA Moslin Ryan M RM Jamison Timothy F TF

Organic letters 20080227 6

Highly substituted, very hindered enones were synthesized using a two-step procedure that utilizes a diiodosamarium-promoted Reformatsky-type coupling and dehydration using Martin sulfurane. Both alpha-chloro- and alpha-bromoketones were coupled with a variety of carbonyl nucleophiles to form the intermediate beta-hydroxyketones, occurring with excellent diastereoselectivity, favoring the syn isomer (R1=Me). This technique complements other methods and enables the preparation of enones outside o ...[more]

PMID: 18302397

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