Some have explored the opposite approach, that is the formation of higher-energy isomers from which lower energy species would emerge; 37,92 so for example Foo et al. have considered bimolecular (not of interest here) and unimolecular routes to acetamide -the latter from N-methyl formamide, acetimidic (ethanimidic) acid, 1-amino ethenol and 2-amino acetaldehyde. They show that the energy barrier for (E,Z ) acetimidic acid → acetamide is 119 kJ mol -1 (this work 130 kJ mol -1 ) whilst the barrier for anti 1-amino ethenol → acetamide is 170 kJ mol -1 ; the latter agrees well with values of 164 and 168 kJ mol -1 from Mardyukov and this work, respectively. Given that species with the C ---N bond are abundant (27 such have been detected ) one might speculate that acid-induced addition of H 2 O could provide a feasible channel: