Studies On The Rhodium Catalyzed Synthesis Of Isoquinoline Derivatives Via C-H Bond Functionalization

The isoquinoline is an important motif in organic chemistry due to its wide exsitence in natural products,pharmaceuticals and materials.Conventional procedures start from phenethylamines or acetals under the condition of strong acid,which not only suffer from limited availability of the substrates and harsh reaction conditions,but also tedious synthesis procedures.In the past ten years,transition metal catalyzed C-H bond functionalization have been developed rapidly to synthesize heterocyclic compounds including isoquinoline derivatives,owning to its atomic economy.However,there are still some problems to overcome,such as requirement of expensive substrates with two functional groups and stoichiommetric amount metel salt as oxident.Herein,an efficient method for rhodium catalyzed synthesis of isoquinoline derivatives through C-H bond activation are developed.The easily available benzylamines and diazo compounds are used as substrates.This protocol features available substrates,mild condition,simple catalytic system and molecular oxygen from air as an oxidant.34 substrates are investigated up to 95% yield,and 32 substrates provide more than 60% yield.Notably,for 7 substrates probably obtaining two products,mono product is observed only in 6 substrates.In conclusion,this method features good reactivity,applicability and regioselectivity as well.