Sulfenylation,Iodination And Catellani/cyclization Of Isoquinolinones And Sulfonylation Of Baylis-Hillman Acetates

Isoquinolinone,phenazinone,and allyl sulfone scaffolds are widely present in natural products and biologically active molecules as a special structural group and show a wide range of biological activities.The incorporation of sulfur atoms can effectively change the physical and chemical properties of molecules,therefore,the development of efficient,green,metal-free catalytic,mild conditions,and highly selective synthetic methods for constructing C-S bonds is a hot point of research in organic synthetic chemistry.Herein,we report a green and efficient synthetic method for the construction of C-S bonds in isoquinolin-1（2H）-ones and Baylis-Hillman acetates.This thesis is composed of following contents.1.The I₂/（Et O）₂P（O）H-promoted regioselective C-4 sulfenylation of isoquinolin-1（2H）-ones using commercially available aryl sulfonyl chlorides as the sulfur source was realized under metal-and solvent-free conditions.Under an air atmosphere,22 4-arylthioisoquinolin-1（2H）-ones was obtained and the yield up to97%.A radical reaction mechanism involving Ar S^●radicals as key intermediates is proposed for the present transformation.2.The p-toluenesulfonic acid-catalyzed iodination of isoquinolin-1（2H）-ones with N-iodosuccinimide to synthesize 4-iodoisoquinolin-1（2H）-ones at room temperature was described.In addition,some（hetero）arenes and heterocycles reacted smoothly under optimal conditions.This method provides an alternative way of constructing C-I bonds,affords various 4-iodoisoquinolin-1（2H）?ones in moderate to good yields,and shows broad substrate scope,and good functional group tolerance.3.The PdCl₂（PPh₃）₂/Cs₂CO₃-catalyzed a three-component tandem Catellani/cyclization reaction for the construction of fused 6-（5H）-phenanthridone skeletons was developed.The skeleton was assembled from 4-iodoisoquinolinone,o-bromobenzoic acid and norbornene（NBE）.The products were characterized by NMR,HRMS and X-ray.The reaction involved Heck reaction,migration insertion,oxidative addition and reductive elimination courses.4.A metal-free and oxidant-free procedure for the sulfonylation of Baylis-Hillman acetates with sulfonyl hydrazides to synthesize allyl sulfone compounds under the irradiation of visible light and open-air conditions at room temperature was reported.The products had Z/E conformation and the Z/E ratio was calculated by ~1H NMR.This transformation has high yields,excellent stereoselectivity,broad substrate scope,good functional group tolerance,and mild reaction conditions.