title: Stereoselective preparation of conjugated (Z)-1,3-enynes by dehydration reactions of allenic bromohydrins and the use of the enynes in base-mediated tandem allylation ene-carbocyclization reactions with β-ketoesters.
abstract: A procedure has been developed for the concise, stereoselective synthesis of (Z)-5-bromo-4-aryl-pent-3-en-1-ynes through Sc(OTf)3catalyzed dehydration reactions of allenic bromohydrins. (Z)-1,3-Enynes are transformed to methylenecyclopentenes when subjected to a sequential, one-pot process involving base mediated allylation reactions with ethyl acetoacetate followed by ene-carbocyclization reactions. An unprecedented rearrangement reaction involving 1,5-acyl migration takes place when the methylenecyclopentenes are treated with acid to form highly substituted cyclopentadienes.
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Mei-Huey
authors.identifier: http://orcid.org/0000-0001-6390-5171
authors.initials: MH
authors.lastname: Lin
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Shih-Hao
authors.initials: SH
authors.lastname: Chiu
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Kung-Yu
authors.initials: KY
authors.lastname: Liang
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Yi-Lin
authors.initials: YL
authors.lastname: Lee
authors.affiliation: Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007. mhlin@cc.ncue.edu.tw.
authors.forename: Tsung-Hsun
authors.initials: TH
authors.lastname: Chuang