Synthesis of 2,5-Disubstituted 3-Iodofurans via Palladium-Catalyzed Coupling and Iodocyclization of Terminal Alkynes
作者:Zhengwang Chen、Gao Huang、Huanfeng Jiang、Huawen Huang、Xiaoyan Pan
DOI:10.1021/jo1023987
日期:2011.2.18
2,5-Disubstituted 3-iodofurans are readily prepared under very mild reaction conditions by the palladium/copper-catalyzed cross-coupling of (Z)-β-bromoenol acetates and terminal alkynes, followed by iodocyclization. The useful intermediates conjugated enyne acetates are obtained in high yields in the transformation. Aryl- and alkyl-substituted alkynes undergo iodocyclization in good yields. The resulting
Catalyst- and Metal-Free Rapid Functionalizations of Alkynes Using TsNBr2
作者:Lal Yadav、Ruchi Chawla、Atul Singh
DOI:10.1055/s-0033-1339194
日期:——
A very rapid (3–12 min) and efficient method has been developed for a one-potsynthesis of α,α-dibromoalkanones and β-bromoenol alkanoates directly fromalkynes using N , N -dibromo- p -toluenesulfonamide (TsNBr 2 ). The protocol is embellished with features like ambient temperature, high regioselectivity, operational simplicity, and metal- and catalyst-free conditions.
已经开发了一种非常快速(3-12 分钟)且有效的方法,用于使用 N , N - 二溴对甲苯磺酰胺 (TsNBr 2 ) 直接从炔烃一锅合成 α,α-二溴链烷酮和 β-溴烯醇链烷酸酯。该协议具有环境温度、高区域选择性、操作简单以及无金属和无催化剂条件等特点。
A Highly Efficient Synthesis of 2,5-Disubstituted Furans from Enyne Acetates Catalyzed by Lewis Acid and Palladium
A highlyefficientsynthesis of a wide range of 2,5-disubstituted furans from enyne acetates is described. The reactions are conducted by using Lewis acid and palladiumcatalyst and provide symmetrical and unsymmetrical products in good to excellent yields, with broad substrate scope, including a variety of aromatic and aliphatic substituents in the 2- and 5-position of the furan ring.