Copper-catalyzed oxidative cross-dehydrogenative coupling of 2H-chromenes and terminal alkynes.

ABSTRACT: An efficient copper-catalyzed cross-dehydrogenative coupling of 2H-chromenes and terminal alkynes mediated by DDQ has been established. A protic additive, EtOH, proved to be crucial for harmonizing the oxidation with a subsequent alkynylation step by retaining the oxidation state of an oxocarbenium ion in the form of acetal. The CDC reaction exhibits a good substrate scope, with a range of terminal aryl- and alkyl alkynes being well tolerated. The copper-catalyzed alkynylation of 2H-chromene acetals with terminal alkynes was also explored.

SUBMITTER: Yang F 

PROVIDER: S-EPMC6051884 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature