42455-41-4Relevant articles and documents
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.
One-pot three-component synthesis of tetrasubstituted N - H pyrroles from secondary propargylic alcohols, 1,3-dicarbonyl compounds and tert-butyl carbamate
Cadierno, Victorio,Gimeno, Jose,Nebra, Noel
experimental part, p. 233 - 236 (2010/04/27)
(Chemical Equation Presented) Several tetrasubstituted N - H pyrroles, functionalized with ester or ketone groups at C-3 position, were prepared by one-pot coupling of secondary propargylic alcohols with 1,3-dicarbonyl compounds and tert-butyl carbamate,
