Abstract
1,4-Migrations of organopalladium and organorhodium species have been utilized for the development of various cascade reactions involving remote C-H bond activation. Recently, we reported a cobalt-catalyzed migratory arylzincation reaction of an alkyne that features alkenyl-to-aryl 1,4-cobalt migration and cobalt-to-zinc transmetalation as key steps. We report herein that the cobalt/arylzinc combination can also promote a cascade arylative cyclization reaction of alkynes bearing pendant ester or ketone moieties to afford benzo-fused cyclic ketone or alcohol products, respectively. The reaction is considered to proceed through insertion of the alkyne into an arylcobalt species, 1,4-cobalt migration, and intramolecular organocobalt addition to the carbonyl group. The present cobalt/arylzinc system may not only serve as an alternative to previously reported rhodium/arylboron and iridium/arylboron systems but also complement their scopes in the arylative cyclization.
Original language | English |
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Pages (from-to) | 3738-3742 |
Number of pages | 5 |
Journal | ACS Catalysis |
Volume | 6 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2016 Jun 3 |
Externally published | Yes |
Keywords
- C-H activation
- alkynes
- cascade reactions
- cobalt
- organozinc reagents
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)