Tandem aldehyde–alkyne–amine coupling/cycloisomerization: A new synthesis of coumarins
نویسندگان
چکیده
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.
منابع مشابه
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