Synthesis And Characterization Of Heterocyclic Compounds Containing Chloro-Substituted Indole Skeleton

Due to its special chemical structure and chemical properites,indole has been the basic structural unit for the construction of important indole-based compounds.Indole and its derivatives have been widely applied in medicine,agricultural chemicals,industrial products,food and high-performance materials.Considerable studies and investigations have confirm that the presence of chloro-substituted indole moiety has been suggested to be a critical prerequisite for biological activity,As such,it would be meaningful work for the design and synthesis of structurally novel chloro-substituted indole-based compounds.This thesis is mainly divided into four parts:In the first part,recent advances on synthesis and applications of chloro-substituted indole compounds were reviewed based on the survey of the relevant literatures over the past few decade.In the second part,7-ethylindoline-2,3-dione 1 was selected as the starting material to react with sulfonyl chloride in refluxing acetic acid as the solvent to obtain the corresponding 5-chloro-7-ethylindoline-2,3-dione 2a,which was further underwent the N-alkylation reaction to give N-alkyl-5-chloro-7-ethylindoline-2,3-dione 2b-2f.The resulting 2a-2f were then subjected to the reaction with1,2-diaminobenzene and thiosemicarbazide to obtain the desired structurally new9-chloro-7-ethyl-6H-indolo[2,3-b]quinoxaline derivatives 3a-3f with 73.2-86.5%yields and 8-chloro-6-ethyl-5H-[1,2,4]triazino[5,6-b]indole-3-thiol derivatives3g-3l with 43.9-82.7%yields,respectively.In the third part,5-chloro-7-ethylindoline-2,3-dione 2a was first underwent the Wolff reduction reaction with hydrazine hydrate to give the corresponding5-chloro-7-ethylindolin-2-one 4,which was then treated under the Vilsmerier-Haack reaction condition to give the expected 2,5-dichloro-7-ethyl-1H-indole-3-carbaldehyde 5a.The resulting 5a and further acetylated derivative1-?2,5-dichloro-7-ethyl-1H-indol-3-yl?ethan-1-one 5b were conducted N-alkylation reaction to give the respective N-alkyl-2,5-dichloro-7-ethylindoline-3-carbal dehydes 6a-6e and 1-?2,5-dichloro-7-ethyl-1-alkyl-1H-indol-3-yl?ethan-1-one 6f-6j.The newly synthesized 6a-6j were finally refluxed with guanidine nitrate in the presence of KOH as the base in refluxing ethanol as the media to give the structurally new 6-chloro-9H-pyrimido[4,5-b]indole-2-amine derivatives 7a-7j in39.6-71.7%yields.In the fourth part,the substituted 1-?2-chloro-1-methyl-1H-indol-3-yl?ethan-1-one 6f-6h and 6j-6x were employed as the substrate to react with2-aminobenzophenone in 40%aqueous methanol media with the presence of KOH as the base under 200 W incandescent light irradiation conditions to synthesize 18novel 11-phenyl-6H-indolo[2,3-b]quinoline derivatives 8f-8h and 8j-8x in yields ranging 12.3%to 49.4%.The structures of all new target compounds have been characterized by IR,¹H NMR,¹³C NMR and HRMS,among which the structures of 8f and 8n were further confirmed by XRD.