A Palladium Iodide-Catalyzed Carbonylative Approach to Functionalized Pyrrole Derivatives
| Autor: | Brunella Maria Aresta, Raffaella Mancuso, Giuseppe Salerno, Lucia Veltri, Bartolo Gabriele, Sabino Maggi |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
chemistry.chemical_classification
Molecular Structure Chemistry Aryl Organic Chemistry Iodide Diastereomer chemistry.chemical_element Stereoisomerism Iodides Medicinal chemistry Catalysis chemistry.chemical_compound Pirrole derivatives Cyclization Organic chemistry Pyrroles Reactivity (chemistry) Heterocyclic compounds Oxidation-Reduction Carbonylation Palladium Alkyl |
| Zdroj: | Journal of organic chemistry 77 (2012): 4005–4016. doi:10.1021/jo300365n info:cnr-pdr/source/autori:Bartolo Gabriele (1); Lucia Veltri (2); Raffaele Mancuso (2); Giuseppe Salerno (2); Sabino Maggi (3); Brunella Aresta (3)/titolo:A Palladium Iodide-Catalyzed Carbonylative Approach to Functionalized Pyrrole Derivatives/doi:10.1021%2Fjo300365n/rivista:Journal of organic chemistry/anno:2012/pagina_da:4005/pagina_a:4016/intervallo_pagine:4005–4016/volume:77 |
| ISSN: | 1520-6904 0022-3263 |
| DOI: | 10.1021/jo300365n |
| Popis: | A novel and convenient approach to functionalized pyrroles is presented, based on Pd-catalyzed oxidative heterocyclization-alkoxycarbonylation of readily available N-Boc-1-amino-3-yn-2-ols. Reactions were carried out in alcoholic solvents at 80-100 °C and under 20 atm (at 25 °C) of a 4:1 mixture of CO-air, in the presence of the PdI(2)-KI catalytic system (2-5 mol % of PdI(2), KI/PdI(2) molar ratio = 10). In the case of N-Boc-1-amino-3-yn-2-ols 3, bearing alkyl or aryl substituents, the carbonylation reaction led to a mixture of Boc-protected and N-unsubstituted pyrrole-3-carboxylic esters 4 and 5, respectively. This mixture could be conveniently and quantitatively converted into deprotected pyrrole-3-carboxylic esters 5 by a simple basic treatment. In the case of diastereomeric (3RS,4RS)- and (3RS,4SR)-N-Boc-3-amino-2-methyldec-5-yn-4-ol (syn-3f and anti-3f, respectively, whose relative configuration was determined by X-ray crystallographic analysis), no particular difference was observed in the reactivity of the two diastereomers between them and with respect to the diastereomeric mixture (3S,4S) + (3S,4R). Interestingly, N-Boc-2-alkynyl-1-amino-3-yn-2-ols 6, bearing an additional alkynyl substituent α to the hydroxyl group, spontaneously underwent N-deprotection under the reaction conditions and regioselective water addition to the alkynyl group at C-3 of the corresponding pyrrole-3-carboxylic ester derivative, thus directly affording highly functionalized pyrrole derivatives 7 in one step. In a similar manner, a novel functionalized dihydropyrrolizine derivative 9 was directly synthesized starting from (S)-7-(pyrrolidin-2-yl)trideca-5,8-diyn-7-ol 8. |
| Databáze: | OpenAIRE |
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