作者:Nour Wasfy、Brian Doan、Faizan Rasheed、Dan Fishlock、Arturo Orellana
DOI:10.1021/acscatal.0c05209
日期:2021.3.19
We report a mild palladium-catalyzed selective dehydrogenation of 4-alkylpyridines that exploits their soft enolization to alkylidene dihydropyridines using allyl chloroformate under metal-free conditions. Treatment of these intermediates with a palladium catalyst liberates an alkylpyridylic anion and an allylpalladium(II) intermediate, which combine and undergo β-hydride elimination to install a double
我们报道了4-烷基吡啶的轻度钯催化的选择性脱氢,它在无金属条件下利用氯甲酸烯丙酯利用它们的软烯醇化成亚烷基二氢吡啶。用钯催化剂处理这些中间体可释放烷基吡啶基阴离子和烯丙基钯(II)中间体,它们结合并经过β-氢化物消除以形成双键。重要的是,气体副产物的形成使该方法非常实用。此外,该反应可耐受多种官能团,包括许多可以使用相似的钯催化反应进行脱氢的官能团,即使在带有多个吡啶位置的底物中,对4-烷基吡啶也具有选择性。