Study on “Urea to Urea” Approach: Access to Unsymmetrical Ureas Bearing Pyridyl Substituents was written by Kasatkina, Svetlana O.;Geyl, Kirill K.;Baykov, Sergey V.;Novikov, Mikhail S.;Boyarskiy, Vadim P.. And the article was included in Advanced Synthesis & Catalysis in 2022.COA of Formula: C7H9NO This article mentions the following:
A protocol for the synthesis of unsym. ureas substituted by pyridyl/quinolinyl moiety was developed. This method concluded in metal- and base-free reamination of N,N-dimethyl-N’-hetaryl ureas with a wide range of aryl and alkyl amines. The isolated yields varied from 40 to 96% depending on the nucleophilicity of the amines. The scope of this method includes more than 50 examples. The reaction was not hindered by either donor or acceptor groups as well as diverse functionalities. The synthesis was easily scaled to gram quantities. Theor. calculations supported by exptl. data allowed to propose a plausible mechanism for the process. This reaction takes place through the intermediate formation of hetaryl isocyanate. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8COA of Formula: C7H9NO).
3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.COA of Formula: C7H9NO