A scarce and interesting C![[double bond, length as m-dash]](http://www.rsc.org/images/entities/char_e001.gif)
C⋯C![[triple bond, length as m-dash]](http://www.rsc.org/images/entities/char_e002.gif)
N π-hole interaction has been found to occur in (E)-3-[(4-halogenphenyl)amino]-2-cyanoprop-2-enoates, which plays an essential role in defining the crystal packing patterns. DFT calculations offer effective support for the interaction. ESPs and NBO analysis further reveal that its nature is both electrostatic interaction and electronic delocalization.
![Graphical abstract: A scarce C [[double bond, length as m-dash]] C⋯C [[triple bond, length as m-dash]] N π-hole interaction in (E)-isomers of 3-[(4-halogenphenyl)amino]-2-cyanoprop-2-enoates](http://hg.y866.cn/compound/lib/scimg/usr/1/C8NJ04000A.jpg)
