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

…, N Thirupathi, M Haribabu

Index: Reddy, Maddi Sridhar; Thirupathi, Nuligonda; Haribabu, Madala Beilstein Journal of Organic Chemistry, 2013 , vol. 9, p. 180 - 184

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Citation Number: 13

Abstract

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.