78950-34-2Relevant academic research and scientific papers
Ligand-Promoted Palladium-Catalyzed C?H Acetoxylation of Simple Arenes
Valderas, Carolina,Naksomboon, Kananat,Fernández-Ibá?ez, M. ángeles
, p. 3213 - 3217 (2016/10/24)
The palladium-catalyzed C?H oxidation of simple arenes is an attractive strategy to obtain phenols, which have many applications in the fine chemicals industry. Although some advances have been made in this research area, low reactivity and selectivity are, in general, observed. This report describes a new catalytic system for the efficient C?H acetoxylation of simple arenes based on Pd(OAc)2 and a pyridinecarboxylic acid ligand.
The first vinyl acetate mediated organocatalytic transesterification of phenols: A step towards sustainability
Kumar, Manoj,Bagchi, Sourav,Sharma, Anuj
supporting information, p. 8329 - 8336 (2015/11/10)
The present report outlines our efforts toward a simple yet elegant protocol for O-acylation of a wide variety of phenols. This highly enabling and solventless method relies on vinyl acetate as an innocuous acyl donor and DABCO as an organocatalyst. Operational simplicity, excellent yields, higher and faster conversion rates without excess reagents, a simple workup and essentially no need of columns are some of the salient features of the reported protocol.
Steric control of site selectivity in the Pd-catalyzed C-H acetoxylation of simple arenes
Cook, Amanda K.,Emmert, Marion H.,Sanford, Melanie S.
supporting information, p. 5428 - 5431 (2013/11/19)
This report describes the use of an oxidant and a ligand to control site selectivity in the Pd(OAc)2-catalyzed C-H acetoxylation of simple arenes. The use of MesI(OAc)2 as the terminal oxidant in combination with acridine as the ligand results in primarily sterically controlled selectivity. In contrast, with Pd(OAc)2 as the catalyst and PhI(OAc)2 as the oxidant, electronic effects dominate the selectivity of arene C-H acetoxylation.
Remarkably high reactivity of Pd(OAc)2/pyridine catalysts: Nondirected C-H oxygenation of arenes
Emmert, Marion H.,Cook, Amanda K.,Xie, Yushu J.,Sanford, Melanie S.
supporting information; experimental part, p. 9409 - 9412 (2011/11/07)
Less is more: The rational optimization and general applicability of the catalytic system Pd(OAc)2/pyridine is described (see scheme). The catalyst shows excellent reactivity in the C-H oxygenation of simple aromatic substrates. The Pd/pyridine ratio is critical as the use of one equivalent of pyridine per Pd center leads to dramatic enhancements in both reactivity and site selectivity in comparison to Pd(OAc)2 alone.
Platinum and palladium complexes containing cationic ligands as catalysts for arene H/D exchange and oxidation
Emmert, Marion H.,Gary, J. Brannon,Villalobos, Janette M.,Sanford, Melanie S.
supporting information; experimental part, p. 5884 - 5886 (2010/11/19)
Cationic catalysts in HD: Palladium(II) and platinum(II) complexes of pyridinium-substituted bipyridine ligands are highly active and stable catalysts for H/D exchange and oxidation of aromatic C-H bonds (TONs up to 3200, TOFs up to 0.1 s-1; se
Substituent effects on homolytic bond dissociation free energies of oxygen-acetyl bonds in phenyl acetates and nitrogen-acetyl bonds in acetanilides
Andersen, Mogens L.
, p. 1045 - 1049 (2007/10/03)
The use of thermochemical cycles makes it possible to determine substituent effects on the homolytic bond dissociation free energies, BDFE, of the oxygen-acetyl bonds in substituted phenyl acetates and the nitrogen-acetyl bonds in substituted acetanilides. A linear correlation between BDFEs for the phenyl acetates and the BDFEs of the oxygen-hydrogen bonds in correspondingly substituted phenols is found with a slope equal to 0.78. An equivalent linear correlation does not exist between the BDFEs of the nitrogen-acetyl bonds in acetanilides and the nitrogen-hydrogen bonds in anilines. This difference in the two correlations of substituent effects on the BDFEs can be explained by the different degrees of stabilization of the parent molecules by the substituents on the phenyl rings. The acetanilides are in this respect extraordinary, since stabilization involving π-resonance plays an important role. Acta Chemica Scandinavica 1996.
