Annelation of lactam rings to 2,3,4,4a-tetrahydro-1H-carbazole derivatives

In the reaction of 4a-methyl-2,3,4,4a-tetrahydro-1H-carbazole and its 6-met hyl- and 6-bromosubslituted derivatives with 2-chloroacetamide respective 9 -carbamoylmethyl-4a-methyl-2,3,4,4a-tetrahydro- 1H-carbazolium chlorides ar e formed, which can be cyclized into 5,6,7,7a-tetrahydro-1H,4H-imidazo[2, 1 -k] carbazol-2(3H)-one derivatives. Reaction of 4a methyl-2,3,4, 4a-tetrahy dro-1H-carbazole hydrochloride with acrylamide gives 4a-methyl-1,2,6,7,8,8a -hexahydro-5H-pyrimido [2,1-k]carbazol-3 (4H)-one. 7a,12-Dimethyl-3,4,4a,5, 6,7,7a,12-octahydropyrido [3,2-j]carbazol-2(1H)-one was synthesized by the reaction of 4a,9-dimethyl-2,3,4,4a-tetrahydro-9H-carbazole with acrylamide.