In 2019,Journal of the American Chemical Society included an article by Zhu, Min; Zheng, Chao; Zhang, Xiao; You, Shu-Li. SDS of cas: 94928-86-6. The article was titled 《Synthesis of Cyclobutane-Fused Angular Tetracyclic Spiroindolines via Visible-Light-Promoted Intramolecular Dearomatization of Indole Derivatives》. The information in the text is summarized as follows:
An intramol. dearomatization of indole derivatives based on visible-light-promoted [2+2] cycloaddition was achieved via energy transfer mechanism. The highly strained cyclobutane-fused angular tetracyclic spiroindolines, which were typically unattainable under thermal conditions, could be directly accessed in high yields (up to 99%) with excellent diastereoselectivity (> 20:1 dr) under mild conditions. The method was also compatible with diverse functional groups and amenable to flexible transformations. In addition, DFT calculations provided guidance on the rational design of substrates and deep understanding of the reaction pathways. This process constituted a rare example of indole functionalization by exploiting visible-light-induced reactivity at the excited states. The results came from multiple reactions, including the reaction of fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6SDS of cas: 94928-86-6)
fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. SDS of cas: 94928-86-6