ABSTRACT
A carbon–nitrogen double bond would result when two of the affinities joined between a carbon and nitrogen atom, and Arthur Hantzsch and Alfred Werner proposed that the isomerism in carbon–carbon double bonds and carbon–nitrogen double bonds would be completely analogous. The isolation of a third isomer of benzilmonoxime would argue in favor of Victor Meyer's theory of restricted rotation in single bonds, and the isolation of isomeric oximes from an unsymmetrical monoketone would support Hantzsch and Werner's theory. Hantzsch largely agreed, noting that all attempts to isolate an asymmetric nitrogen atom had been fruitless, and that several analogs of carbon–carbon double bonds implied by his theory were unknown, such as the analog ofmaleic and fumaric acid or stilbene. Furthermore, simple imine compounds did not exhibit isomerism, nor did it seem possible to perform additions to the carbon–nitrogen triple bond in a manner similar to the addition to the carbon–carbon triple bond.
