Access to benzo-fused nine-membered heterocyclic alkenes with a trifluoromethyl carbinol moiety via a double decarboxylative formal ring-expansion process under palladium catalysis. Issue 13 (23rd February 2018)

• Record Type: Journal Article
• Authors: Das, Pulakesh; Gondo, Satoshi; Nagender, Punna; Uno, Hiroto; Tokunaga, Etsuko; Shibata, Norio
• Is Part Of: Chemical science. Volume 9:Issue 13(2018)
• Page Start: 3276
• Page End: 3281
• Publication Date: 2018-02-23
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7sc05447e
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Direct access to benzo-fused nine-membered heterocyclic alkenes with a trifluoromethyl carbinol moiety was achieved via a palladium-catalysis. Abstract : Direct access to pharmaceutically attractive benzo-fused nine-membered heterocyclic alkenes3 with a trifluoromethyl carbinol moiety was achieved via a palladium-catalyzed double-decarboxylative formal ring-expansion process from six-membered trifluoromethyl benzo[ d ][1, 3]oxazinones1 to nine-membered trifluoromethyl benzo[ c ][1, 5]oxazonines3 in the presence of vinylethylene carbonates2 . Generation of a Pd-π-allyl zwitterionic intermediate was proposed in the catalytic cycle. The trifluoromethyl group in the benzoxazinanones1 plays an important role throughout the transformation. Diastereoselective chemical transformations of products3 were also demonstrated.