89649-56-9Relevant academic research and scientific papers
Pyrrole Chemistry. An Improved Synthesis of Ethyl Pyrrole-2-carboxylate Esters from Diethyl Aminomalonate
Paine, John B.,Dolphin, David
, p. 5598 - 5604 (2007/10/02)
Ethyl pyrrole-2-carboxylates, versatile precursors for the total synthesis of both synthetic model and naturally occurring tetrapyrroles and porphyrins, can be prepared in greatly improved yields by the addition of 1,3-diketones and preformed diethyl aminomalonate to boiling glacial acetic acid.The method is suitable for both small- and large-scale synthesis and has proved far more reliable than the original in situ dissolving zinc reduction of diethyl oximinomalonate discovered by Kleinspehn.Yields range from 60-70percent for the dominant product isomer from unsymmetrical diketones to 75-90percent for the single product derived from symmetrical diketones.Seventeen examples of alkyl-substituted ethyl pyrrole-2-carboxylates are provided.Improved procedures are given for the preparation of the required precursors.
The Synthesis and Chemistry of Azolenines. Part 2. A General Synthesis of Pyrrole-2-carboxylic Acid Derivatives by the Reaction of 2H-Azirines with Enamines, and the Crystal and Molecular Structure of Ethyl 3-Phenyl-4,5,6,7-tetrahydroindole-2-carboxylate
Law, Kam Wah,Lai, Ting-Fong,Sammes, Michael P.,Katritzky, Alan R.,Mak, Thomas C.W.
, p. 111 - 118 (2007/10/02)
A new general synthesis of 1H-pyrrole-2-carboxylic acid derivatives is described.Reaction between appropriately substituted 2H-azirines and enamines gives a mixture of 2,3- and 3,4-dihydropyrroles, which on acid treatment yields the title compounds in mod
