Synthesis of 2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a][1,4]diazepines and 11-methyl-2,3,4,5-tetrahydro-1H-[1,4]diazepino[1,2-a]indoles

Abstract

3-(Pyrrol-1-yl)-1-propylamine (1) and 3-(3-methyl-indol-1-yl)-propylamine (7) were condensed with (1-hydroxymethyl)benzotriazole to give 2-(1H-1,2,3-benzotriazol-1-yl-methyl)-2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a][1,4] diazepine (2) (55%) and 2-(1H-1,2,3-benzotriazol-1-ylmethyl)-11-methyl-2,3,4,5- tetrahydro-1H-[1,4]diazepino[1,2-a]indole (8) (51%) respectively. Nucleophilic substitutions of the benzotriazolyl group in 2 and 8 with Grignard reagents, sodium borohydride, sodium cyanide and triethyl phosphite gave novel 2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a][1,4]diazepines (3-6) and 11-methyl-2,3,4,5-tetrahydro-1H-[1,4]diazepino[1,2-a]indoles (9-11) in good yields.