Synthesis Of Quinolin-2-ones Derivatives Via NHC-Catalyzed Cascade Reaction

N-Heterocyclic carbenes?NHCs?play an important role as organocatalysts in organic synthesis.The thesis consists of three parts:Chapter 1.This part mainly reviews the application of the formation of enolate and homoenolate intermediates from the N-heterocyclic carbenes-catalyzed saturated carboxylic acids and carboxylic acid esters as well as the formation of?,?-unsaturated acylazolium intermediate from the N-heterocyclic carbenes-catalyzed?,?-unsaturated carboxylic acids and carboxylic acid esters in the organic synthesis.Chapter 2.We have developed an efficient N-heterocyclic carbenes-catalyzed aldol-lactamization-dehydration cascade reaction of 4-nitrophenyl 2-phenylacetates with N-?2-acetyl-phenyl?-4-methylbenzenesulfonamide for the synthesis of quinolin-2-one and coumarin derivatives.The cascade reaction offers good tolerance and occurs under mild conditions,simple operation and good yields.This methodology provides simple and highly efficient entries for synthesis of quinolin-2-one and coumarin derivatives.Chapter 3.Naphthoisoxazoles are known to possess important biological activities.5-Acetoxy-1-naphthoic acid was synthesized by diazotization,iodination,Willamson,CO₂insertion,deprotection and esterification reactions from 5-amino-1-naphthol.The further synthesis of the titled compound 3-?2-morpholinoethyl?naphtho[2,1-d]isoxazole-6-carboxylic acid is ongoing.