A variety of polysubstituted3-iodopyrans were readily prepared in good to excellent yield under mild reaction conditions by the reaction of alkynyl carboxamides with ICl, I(2), and NIS. The products obtained from this process are versatile materials that can be used to construct other complex functionalized pyran structures of importance. The occurrence of the pyranyl group in both natural products
An Intramolecular Cycloaddition Approach to Construct Polysubstituted Pyrrolidones from Alkynyl Carboxamides and PTSA
作者:Xiao-Dan Han、Chuan-Qing Ren、Jian-Ping Fu、Wei Xiong、Hui-Bin Wang、Xiao-Na Dong、Jian-Wei Ji、Ju-Wu Hu
DOI:10.1055/s-0036-1588500
日期:2017.10
Abstract An efficient synthetic route to highlysubstituted pyrrolidone derivatives has been developed from an easily available alkynyl carboxamide and 4-methylbenzenesulfonic acid (PTSA). In the reaction, PTSA is not only used as acidcatalyst but also as a reactant to provide a source for OTs group. A mechanism is proposed to involve the protonation of the alcohol substrate/cyclopropylcarbinol-homoallylic