Synthesis of 3-Alkoxy-4-Pyrrolin-2-ones via Rhodium(II)-Catalyzed Denitrogenative Transannulation of 1<i>H</i>-1,2,3-Triazoles with Diazo Esters
作者:Alexander N. Koronatov、Nikolai V. Rostovskii、Alexander F. Khlebnikov、Mikhail S. Novikov
DOI:10.1021/acs.orglett.0c02893
日期:2020.10.16
method for the synthesis of densely substituted 4-pyrrolin-2-ones by Rh(II)-catalyzed denitrogenative transannulation of 1-alkyl-4-aryl-1H-1,2,3-triazoles with diazo esters has been developed. The reaction proceeds via an attack of the rhodium-bound carbene at the N2 atom of the triazole and the formation of unstable 3,4-dihydro-1,2,4-triazine, which further undergoes ring contraction to a 4-pyrrolin-2-one
已经开发了一种通过Rh(II)催化的1-烷基-4-芳基-1 H -1,2,3-三唑与重氮酯的脱氮脱环合成高取代度的4-吡咯啉-2-酮的方法。该反应通过在三唑的N2原子上与铑结合的卡宾的攻击和不稳定的3,4-二氢-1,2,4-三嗪的形成而发生,该化合物进一步经历环收缩成4-吡咯啉-2 -在铑催化下。该方法不适用于在C4处具有伯烷基取代基的1,2,3-三唑,该化合物可提供稳定的1,2,3-三唑-3-鎓烷基化物作为主要产物。