Synthesis of Benzimidazole-Fused Medium-Sized <i>N,S</i>
-Heterocycles via Palladium-Catalyzed Cyclizations
作者:Alexandra Basilio Lopes、Patrick Wagner、Mihaela Gulea
DOI:10.1002/ejoc.201801686
日期:2019.2.14
Benzimidazole‐fused medium‐sized N,S‐heterocycles (8 to 10 ring atoms) having an exocyclic double bond were synthesized by using exo‐dig Pd‐catalyzed reductive cyclizations. In the case of two substrates bearing an N‐homopropargyl chain, a competing endo‐dig cyclocarbopalladation occurred, leading to rarely encountered 10‐ and 11‐membered N,S‐heterocycles with an endocyclic double bond.
苯并咪唑稠合的具有外环双键的中型N,S杂环(8至10个环原子)是通过exo -dig Pd催化的还原环化反应合成的。在两个带有N-高炔丙基链的底物的情况下,发生了竞争性的内挖-环缩羰化反应,导致很少遇到的带有内环双键的10和11元N,S-杂环。