The detection of cyanoformaldehyde (HCOCN) was reported in 2008 by Remijan et al. in Sgr B2(N) on the basis of observations made with the Green Bank Telescope. Confirming observations have not yet been reported. Gerin et al. had searched for HCOCN in the late 1980s and failed to find any of its various rotational lines from about 86 to 106 GHz as well as one feature near 217 GHz. Since these spectral ranges are congested with lines from known species such as ethyl cyanide and methyl formate, Remijan and coworkers searched at centimeter wavelengths.

While it is a closed-shell species, Lewis-Bevan et al. found that HCOCN reacts easily with water in the gas phase, yielding formic acid and hydrogen cyanide. This instability precludes cyanoformaldehyde from having any practical applications in terrestrial chemistry.