Abstract–Interaction of indolylzinc chloride with 2-chloro-3-nitrothiophene gave 3-(3- nitrothien-2-yl) indole (7) which was converted, via reduction followed by acylation, into 3-(3- acylaminothien-2-yl) indoles (9a-c). Cyclization of 9a-c induced by phosphorus oxychloride under Bischler-Napieralski reaction conditions, took place regioselectively at the indolic C-4 locus to furnish the respective thieno [2', 3': 6, 7] azepino [5, 4, 3-cd] indoles (3a-c).
![4-chloro-N-[2-(1H-indol-3-yl)thiophen-3-yl]benzamide Structure](https://image.chemsrc.com/caspic/238/500022-51-5.png)
