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Tandem aldehyde-alkyne-amine coupling/cycloisomerization: A new synthesis of coumarins.

ABSTRACT: Cu-catalyzed A(3) coupling of ethoxyacetylene, pyrrolidine and salicylaldehydes led to a concomitant cycloisomerization followed by hydrolysis of the resultant vinyl ether to afford coumarins in a cascade process. The reaction proceeded through exclusive 6-endo-dig cyclization and is compatible with halo and keto groups giving coumarins in good to moderate yields.

SUBMITTER: Reddy MS

PROVIDER: S-EPMC3566765 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Tandem aldehyde-alkyne-amine coupling/cycloisomerization: A new synthesis of coumarins.

Reddy Maddi Sridhar MS Thirupathi Nuligonda N Haribabu Madala M

Beilstein journal of organic chemistry 20130128

Cu-catalyzed A(3) coupling of ethoxyacetylene, pyrrolidine and salicylaldehydes led to a concomitant cycloisomerization followed by hydrolysis of the resultant vinyl ether to afford coumarins in a cascade process. The reaction proceeded through exclusive 6-endo-dig cyclization and is compatible with halo and keto groups giving coumarins in good to moderate yields. ...[more]

PMID: 23400373

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