Palladium-Titanium Relay Catalysis Enables Switch from Alkoxide-π-Allyl to Dienolate Reactivity for Spiro-Heterocycle Synthesis
作者:Li-Cheng Yang、Zher Yin Tan、Zi-Qiang Rong、Ruoyang Liu、Ya-Nong Wang、Yu Zhao
DOI:10.1002/anie.201804160
日期:2018.6.25
and [6,5] spiro‐heterocycles under Lewis‐acid‐assisted palladium catalysis. In particular, an unprecedented switch from alkoxide‐π‐allyl to dienolate reactivity was achieved by the use of palladium‐titanium relay catalysis, and represents umpolung reactivity of vinylethylene carbonates. This method uses a simple procedure and commercially available catalysts, and delivers both classes of spiro‐heterocycles
本文报道的是路易斯酸辅助钯催化下[5,5]和[6,5]螺杂环的不同合成。特别是,通过使用钯-钛中继催化,实现了前所未有的从醇盐-π-烯丙基到二烯酸酯反应性的转变,这代表了碳酸乙烯基亚乙酯的固体反应性。该方法使用简单的方法和可商购的催化剂,并以高收率和一致优异的非对映选择性提供两种类型的螺-杂环,并带有三个连续的立体中心。