title: Efficient assembly of chromone skeleton from 2,3-allenoic acids and benzynes.
abstract: Chromone derivatives were synthesized from 2,3-allenoic acids and benzynes in moderate to excellent yields under mild conditions. Instead of the cyclic conjugate addition of the intermediate A formed by the nucleophilic addition of allenoic acid with benzyne, this intermediate undergoes 1,2-addition with the carbonyl group, which was followed by the ring opening, conjugate addition, and protonolysis to afford chromone derivatives. This protocol allows the diversity due to the substituent-loading capability of 2,3-allenoic acids as well as benzynes.
authors.affiliation: Laboratory of Molecular Recognition and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, PR China.
authors.forename: Guobi
authors.initials: G
authors.lastname: Chai
authors.forename: Youai
authors.initials: Y
authors.lastname: Qiu
authors.forename: Chunling
authors.initials: C
authors.lastname: Fu
authors.forename: Shengming
authors.initials: S
authors.lastname: Ma
mesh_terms: D001554:Benzene / Q000737:chemistry*; D002867:Chromones / Q000138:chemical synthesis*; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000737:chemistry*
chemical_list: D002867:Chromones; D009281:Naphthalenes; C110055:allenolic acid; D001554:Benzene