When the carbonyl group is joined directly to carbon and hydrogen (aldehydic) or to carbon and carbon (ketonic) it reacts with phenylhydrazine to give the corresponding phenylhydrazone. When the radical is joined directly to nitrogen and hydrogen, as in formanilide, the products are aniline and formylphenylhydrazine. Substitution productions of formanilide behave similarly. If the radical is joined directly to nitrogen and nitrogen, as in diphenylurea, the products are aniline and a semicarbazide. The corresponding thiourea behaves similarly, and gives a thiosemicarbazide. If the reaction with the thioureas is carried out in the presence of a desulphurizing agent, guanidine derivatives are obtained.
Proceedings of the Iowa Academy of Science
©1931 Iowa Academy of Science, Inc.
Raiford, L. Chas.; Webster, Victor S.; and Potter, Dwight J..
"Further Observations on the Behavior of Vanillin Substitution Products: (a) The Perkin Reaction; (b) The Preparation of Substituted Vanillic Acids,"
Proceedings of the Iowa Academy of Science, 38(1), 171-171.
Available at: https://scholarworks.uni.edu/pias/vol38/iss1/35