Department of Chemistry, Government Arts College. Ootacamund-643 002, Tamilnadn Manuscript received 23 April 1980, accepted 29 October 1980 Reaction of 2-chloro-3-vinylquinolines with sodium hydrogen selenide in boiling ethanol gave the corresponding 1,2-diselenolo(3,4-b)quinolines. Likewise 2-chloro-3- (1',2'-dibromoethyl)-4-phenylquinoline furnished the corresponding 1,2-diselenolo(3,4-b)- quinoline through a novel debromination process. A reaction mechanism has been described.