Highly Selective Palladium-Catalyzed Synthesis of Protected α,β-Unsaturated Methyl Ketones and 2-Alkoxy-1,3-butadienes. High-Speed Chemistry by Microwave Flash Heating
作者:Karl S. A. Vallin、Mats Larhed、Katarina Johansson、Anders Hallberg
DOI:10.1021/jo000070o
日期:2000.7.1
is described for the direct synthesis of 2-alkene-2-methyl-1,3-dioxolanes via regiocontrolled Heck vinylation of commercially available 2-hydroxyethyl vinyl ether. The procedure permits chemoselective transformation of a vinylic triflate or bromide into a blocked alpha,beta-unsaturated methyl ketone. Furthermore, a significantly improved and highly regioselective synthesis of 2-alkoxy-1,3-butadienes
描述了通过可商购的2-羟乙基乙烯基醚的区域控制的Heck乙烯基化直接合成2-烯烃-2-甲基-1,3-二氧戊环的选择性和温和的方法。该方法允许将三氟乙烯或溴化乙烯化学选择性转化为嵌段的α,β-不饱和甲基酮。此外,已经开发出显着改善的和高度区域选择性的2-烷氧基-1,3-丁二烯合成。通过微波辐射的闪蒸加热促进了钯催化的反应,并且在5-7分钟的反应时间之后,原料被完全转化。