42455-47-0Relevant academic research and scientific papers
Ring-contraction of hantzsch esters and their derivatives to pyrrolesviaelectrochemical extrusion of ethyl acetate out of aromatic rings
Liu, Xu,Liu, Chang,Cheng, Xu
, p. 3468 - 3473 (2021/05/21)
Electrochemical ring-contraction of HEs and theirs pyridine derivatives is developed to obtain polysubstituted pyrroles. This process provides an orthogonal utilization of Hantzsch esters for the well-documented application as side chain or hydrogen donors. The formal transformation shows an extrusion of ethyl acetate out of the pyridine ring in a single step. In addition to the novel transformation, we also discovered the Lewis acid's intermolecular control of regioselectivity during an intramolecular electrochemical process. The reaction provides a number of polysubstituted pyrroles that have never been accessed, including pharmaceutical intermediates and photoswitches. An unusual 4-electron continuous reduction drives the unprecedented anionic dearomatization/ring-contraction/rearomatization pathway.
