Merging C-H Vinylation with Switchable 6π-Electrocyclizations for Divergent Heterocycle Synthesis was written by Jiang, Xunjin;Zeng, Zhixiong;Hua, Yuhui;Xu, Beibei;Shen, Yang;Xiong, Jing;Qiu, Huijuan;Wu, Yifan;Hu, Tianhui;Zhang, Yandong. And the article was included in Journal of the American Chemical Society in 2020.SDS of cas: 4373-61-9 This article mentions the following:
Pyridinium-containing polyheterocycles exhibit distinctive biol. properties and interesting electrochem. and optical properties and thus are widely used as drugs, functional materials, and photocatalysts. Here, we describe a unified two-step strategy by merging Rh-catalyzed C-H vinylation with two switchable electrocyclizations, including aza-6π-electrocyclization and all-carbon-6π-electrocyclization, for rapid and divergent access to dihydropyridoisoquinoliniums and dihydrobenzoquinolines. Through computation, the high selectivity of aza-electrocyclization in the presence of an appropriate “HCl” source under either thermal conditions or photochem. conditions is shown to result from the favorable kinetics and symmetries of frontier orbitals. We further demonstrated the value of this protocol by the synthesis of several complex pyridinium-containing polyheterocycles, including the two alkaloids berberine and chelerythrine. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9SDS of cas: 4373-61-9).
2-(m-Tolyl)pyridine (cas: 4373-61-9) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.SDS of cas: 4373-61-9