Synthesis and Pyrolytic and Kinetic Behaviour of β,δ′-Dioxo-Stabilised Phosphorus Ylides: Convenient Preparation of γ,δ-Alkynyl Ketones and 2,3-Functionalised Butadienes
作者:R. Alan Aitken、Nouria A. Al-Awadi、Mark E. Balkovich、Hans Jürgen Bestmann、Oliver Clem、Scott Gibson、Andreas Groß、Ajith Kumar、Thomas Röder
DOI:10.1002/ejoc.200390127
日期:2003.3
ketone- and ester-stabilised phosphorus ylides undergo Michael addition to vinyl ketones to give the β,δ′-dioxo ylides 3 and 5, respectively, although in the latter case careful temperature control is required to avoid an undesired side-reaction. Under conditions of flash vacuum pyrolysis at 650 °C the ylides 3 generally undergo Ph3PO extrusion to afford the γ,δ-alkynyl ketones 14, although these are found
酮和酯稳定的磷叶立德都经过迈克尔加成到乙烯基酮,分别得到 β,δ'-二氧代叶立德 3 和 5,尽管在后一种情况下需要仔细控制温度以避免不希望的副反应。在 650 °C 的快速真空热解条件下,叶立德 3 通常经历 Ph3PO 挤出以提供 γ,δ-炔基酮 14,尽管发现它们部分经历了二次裂解。相反,叶立德5在相同条件下反应以通过环丁烯的方式得到合成有用的1,3-二烯20。报告了所选叶立德 3 和 5 反应的速率常数。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)