Zeolite‐promoted Synthesis of Coumarins and Thiocoumarins
作者:Olesia Zaitceva、Valérie Bénéteau、Dmitry S. Ryabukhin、Benoit Louis、Aleksander V. Vasilyev、Patrick Pale
DOI:10.1002/cctc.201901384
日期:2020.1.8
Acidic zeolites, especially faujasites, efficientlypromote the intramolecular cyclization of aryl propynoates and propynethioates, which produces coumarins and thiocoumarins, usually in high yields. Comparison with homogeneous Lewis or BrØnsted acids and with heterogeneous related sieve materials revealed the prevalence of zeolites exhibiting large cage‐type pores (H‐USY) for such cyclizations. Various