The Pd-catalyzed synthesis of benzofused carbo- and heterocycles through carbene migratory insertion/carbopalladation cascades with tosylhydrazones
作者:Miguel Paraja、M. Carmen Pérez-Aguilar、Carlos Valdés
DOI:10.1039/c5cc06348e
日期:——
Indenes and benzofurans are synthesized from tosylhydrazones and o-substituted aryliodides through a Pd-catalyzed carbene migratory insertion/intramolecular carbopalladation cascade reaction.
A variety of mono- and disubstituted phenols are alkylated with propargyl bromide to give phenyl 2-propynyl ethers, which were further coupled with aryliodides under Sonogashira reaction conditions to give 3-phenoxy-1-aryl-1-propyne derivatives. The latter compounds underwent an initial Claisen rearrangement followed by ring closure to give functionalized benzo[b]furans in moderate to good yields
用炔丙基溴将各种单取代和二取代的苯酚烷基化,得到苯基2-丙炔基醚,然后在Sonogashira反应条件下将其与芳基碘化物偶合,得到3-苯氧基-1-芳基-1-丙炔衍生物。后面的化合物先进行克莱森重排,然后闭环,以中等至良好的收率得到官能化的苯并[ b ]呋喃。