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Published on: June 21, 2017
Rh-Catalyzed aldehydic C-H alkynylation and annulation
Maddali L N Rao1, Boddu S Ramakrishna
1Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, UP, India. maddali@iitk.ac.in.
Abstract:
Novel Rh-catalyzed aldehydic C-H bond alkynylation and annulation for the in situ synthesis of chromones and aurones are described. It involves the sequential aldehyde C-H bond alkynylation of salicylaldehyde with in situ generated 1-bromoalkyne from 1,1-dibromoalkene followed by annulation. This protocol shows good functional group tolerance including aryl, alkenyl, alkyl and heteroaryl-1,1-dibromoalkenes. The steric/electronic effect was demonstrated during the base-mediated in situ cyclization of o-hydroxyynones to generate aurones.
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