The detection of the E isomer of cyanomethanimine (E-HNCHCN) was published in 2013 by Zaleski and co-workers toward the Sagittarius B2(N) region in the center of the galaxy as observed with the Green Bank Telescope. The discovery team included four undergraduates who were participating in a summer program for minority students. The data upon which the detection was based was drawn from the PRIMOS survey.

E-cyanomethanimine and its Z-cyanomethanimine isomer are important precursors to biological molecules and have thus received a fair amount of recent attention beyond their detections. In addition to papers by Melosso et al., Puzzarini, Vazart et al., and Zhang et al. cited in the entry for Z-cyanomethanimine, Shingledecker et al. characterized new formation reactions for the isomers and incorporated them into a modeling study, Barone & Puzzarini also characterized new formation pathways, and Vasconcelos et al. studied cyanomethanimine synthesis in irradiated N₂-CH₄ ice and its role on outer solar system bodies.

Finally, E-cyanomethanimine is one of the dozens of cyano, isocyano, and cyanide species detected to date.