title: Synthesis of multisubstituted 2-(dihydrofuran-2(3H)-ylidene)acetates via intramolecular carboalkoxylation by platinum-olefin catalyst system.
abstract: The cyclization of 6-(1-alkoxyethyl)hex-2-ynoates in the presence of a platinum-olefin catalyst system gave the corresponding multisubstituted 2-(dihydrofuran-2(3H)-ylidene)acetates in good to high yields. The Z/E selectivity is controlled by the electronic property of the ester group; the 2,2,2-trichloroethyl ester led to the Z isomer, while the phenyl ester gave the E isomer.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan. itaru-n@mail.tains.tohoku.ac.jp
authors.forename: Itaru
authors.initials: I
authors.lastname: Nakamura
authors.forename: Ching Siew
authors.initials: CS
authors.lastname: Chan
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Araki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Terada
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Yamamoto