Synthesis Of Three New Kinds Of Heterocycles: Indolo[3, 2-c] Pyrazolo [1, 5-a] Quinoline, Imidazo[4, 5-c]-pyrazolo[1, 5-a] Quinoline And Dipyrazolo[1, 5-a: 4', 3'-c] Quinoline By Photooxidation And Photocyclization

Photocyclizations contribute to an important approach to the existing repertoire of carbon-carbon bond-forming reactions by allowing access to exceptional molecular structures that cannot be obtained by traditional way. So photocyclization usually as key steps in natural product synthesis.This thesis mainly deals with on the one-pot synthesis of Indolo[3,2-c] pyrazolo[1,5-a]-quinoline, Imidazo[4,5-c]pyrazolo[1,5-a]quinoline and Dipyrazolo[1, 5-a:4',3'-c]quinoline, by photooxidation and photocyclization. It consists of two parts:In Partâ… , a review on photocyclizations was introduced and the applications of photocyclization as key steps in natural product synthesis was also discussed.In Part twoâ…¡, first of all, three kinds of substrates,5-(2-chloroindol-3-y)-1-pheny 1-4,5-dihydropyrazoles,5-(5-chloropyrazol-4-yl)-1-pheny1-4,5-dihydropyra zoles and 5-(5-chloroimidazol-4-yl)-1-phenyl-4,5-dihydropyraz oles, was syntheted.The synthesis and characterization of three kinds of substrates and new heterocyclic molecules, i.e, Indolo[3,2-c] pyrazolo[1,5-a]quinoline, Imidazo[4,5-c] pyrazolo[1,5-a] quinoline and Dipyrazolo[1,5-a:4',3'-c]quinoline, have been invest igated. A novel and efficient way was employed to synthesis these three new heterocyclic systems. In the procedures to target products, all the synthetic moleculars were charactereted by 1 HNMR or 13CNMR.