Ethyl (2,3-dihydro-1H,1′H-2,3′-biindol-1-yl)glyoxylate

The crystal structure of the title compound, C 20 H 18 N 2 O 3 , was determined in the course of our studies of the synthesis of 3-acylindole derivatives. We obtained it as an unexpected racemic side product. The crystal structure contains chains of dimers along the a axis.