The synthesis of pyridothiazepines has been achieved via a 1,5‐dipolarcycloadditionreaction between pyridinium 1,4‐zwitterionic thiolates and activated allenes conducted under thermal conditions. Meanwhile, a ring‐contraction reaction of the resulting pyridothiazepine derivatives via the extrusion of 3‐thioxoacrylates has also been described.
<i>Cinchona</i> Alkaloid Catalyzed Enantioselective [4 + 2] Annulation of Allenic Esters and <i>in Situ</i> Generated <i>ortho</i>-Quinone Methides: Asymmetric Synthesis of Functionalized Chromans
作者:Yu-Hua Deng、Wen-Dao Chu、Xiang-Zhi Zhang、Xu Yan、Ke-Yin Yu、Liang-Liang Yang、Hanmin Huang、Chun-An Fan
DOI:10.1021/acs.joc.7b00370
日期:2017.5.19
A novel enantioselective [4 + 2] annulation of the allenoates having a unique positive ortho-effect with in situ generated ortho-quinone methides has been developed under the catalysis of Cinchonaalkaloid. This chiral amine-catalyzed reaction provides an alternative route to asymmetric catalytic construction of synthetically interesting, highly functionalized chiral chromans in good to excellent
作者:Himbert, Gerhard、Fink, Dieter、Diehl, Klaus、Rademacher, Paul、Bittner, Andreas J.
DOI:——
日期:——
Enantioselective Intermolecular [2 + 2 + 2] Cycloadditions of Ene–Allenes with Allenoates
作者:Andrew T. Brusoe、Rahul V. Edwankar、Erik J. Alexanian
DOI:10.1021/ol303024q
日期:2012.12.7
An enantioselective [2 + 2 + 2] cycloaddition of ene-allenes with allenoates is described, which transforms simple pi-components into stereochemically complex carbocycles in a single step. The rhodium(I)-catalyzed cycloaddition proceeds with good levels of enantioselectivity, and with high levels of regio-, chemo-, and diastereoselectivity. Our results are consistent with a mechanism involving an enantioselective intermolecular allene-allene oxidative coupling.
HIMBERT, GERHARD;FINK, DIETER;DIEHL, KLAUS;RADEMACHER, PAUL;BITTNER, ANDR+, CHEM. BER., 122,(1989) N, C. 1161-1173