Ethyl isocyanide was the subject of a search reported in 2018 by Margulès et al. using data generated for that purpose. Based on the 2906 transitions now assigned, the compound was not detected toward either Orion KL or toward Sgr B2. Some of the observations were made with the IRAM 30m telescope. Existing ALMA data was also checked for Orion.

Far fewer isocyanide species have been detected in space than cyanide species, but the ones that are known include hydrogen isocyanide (HNC), methyl isocyanide (CH₃NC), isocyanoacetylene (HCCNC), aluminum isocyanide (AlNC), silicon isocyanide (SiNC), magnesium isocyanide (MgNC), hydromagnesium isocyanide (HMgNC), and isocyanogen (CNCN). The cyano isomer of ethyl isocyanide was deteced in 1977.