title: Site- and Regioselective Monoalkenylation of Pyrroles with Alkynes via Cp*CoIIICatalysis.
abstract: A site-, regio-, syn-, and monoselective alkenylation of dimethylcarbamoyl-protected pyrroles proceeded using a catalytic amount of [Cp*Co(CH3CN)3](SbF6)2and KOAc. A variety of internal alkynes with several functional groups and a terminal alkyne afforded hydropyrrolation products in a selective manner in good to excellent yield. The site-selectivity (C2/C5 selectivity) observed for C3-substituted pyrroles is noteworthy because Cp*RhIII-catalyzed conditions afforded only a moderate yield and low selectivity. The conditions described here provide general and straightforward access to unsymmetrically mono- and disubstituted pyrrole derivatives.
authors: Faculty of Pharmaceutical Sciences, Hokkaido University , Sapporo 060-0812, Japan.
authors: Ryo
authors: R
authors: Tanaka
authors: Graduate School of Pharmaceutical Sciences, The University of Tokyo , Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors: Hideya
authors: H
authors: Ikemoto
authors: Graduate School of Pharmaceutical Sciences, The University of Tokyo , Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors: Motomu
authors: M
authors: Kanai
authors: Faculty of Pharmaceutical Sciences, Hokkaido University , Sapporo 060-0812, Japan.|ACT-C, Japan Science and Technology Agency, Sapporo 060-0812, Japan.
authors: Tatsuhiko
authors: T
authors: Yoshino
authors: Faculty of Pharmaceutical Sciences, Hokkaido University , Sapporo 060-0812, Japan.|ACT-C, Japan Science and Technology Agency, Sapporo 060-0812, Japan.
authors: Shigeki
authors: S
authors: Matsunaga