Rad transition: The combination of transition‐metal‐catalyzed CHactivation and a NHPI‐initiated radical process is essential for the title transformation. The neutral conditions and the ideal oxidant, molecular oxygen, make this hydroxylation environmentally friendly and practical. NHPI=N‐hydroxyphthalimide.
Triarylbismuthanes as Threefold Aryl-Transfer Reagents in Regioselective Cross-Coupling Reactions with Bromopyridines and Quinolines
作者:Maddali L. N. Rao、Ritesh J. Dhanorkar
DOI:10.1002/ejoc.201402455
日期:2014.8
Cross-coupling studies using bromopyridines and bromoquinolines with triarylbismuths as threefold coupling reagents in substoichiometric amounts under Pd-catalysed conditions are disclosed. The reactivity was high with both mono- and dibromopyridyl substrates, and mono- and bis-couplings were carried out regioselectively. A library of monoaryl and diaryl pyridines was formed in high yields. A one-pot
Directed <i>ortho</i> C–H borylation catalyzed using Cp*Rh(<scp>iii</scp>)–NHC complexes
作者:Jompol Thongpaen、Thibault E. Schmid、Loic Toupet、Vincent Dorcet、Marc Mauduit、Olivier Baslé
DOI:10.1039/c8cc03144d
日期:——
bidentate NHC-carboxylate ligands were efficiently synthesized and fully characterized including solid-state structures. These unprecedented rhodium(III) complexes demonstrated high selectivity in pyridine-directed ortho-C–H borylation of arenes under mild conditions.
Aerobic Oxidation of Pd<sup>II</sup> to Pd<sup>IV</sup> by Active Radical Reactants: Direct C–H Nitration and Acylation of Arenes via Oxygenation Process with Molecular Oxygen
oxidative C–H nitration and acylation of arenes with simple and readily available tert-butyl nitrite (TBN) and toluene as the radical precursors has been developed. Molecular oxygen is employed as the terminal oxidant and oxygen source to initiate the active radical reactants. Many different directing groups such as pyridine, pyrimidine, pyrazole, pyridol, pyridylketone, oxime, and azo groups can be employed
已经开发了钯催化的好氧氧化C–H硝化和芳烃与简单易用的亚硝酸叔丁酯(TBN)和甲苯作为自由基前体的酰化反应。分子氧被用作末端氧化剂和氧源以引发活性自由基反应物。在这些新颖的转化中可以使用许多不同的导向基团,例如吡啶,嘧啶,吡唑,吡啶醇,吡啶基酮,肟和偶氮基团。通过自由基过程的Pd II / Pd IV催化循环是这些氧化的CH–H硝化和酰化反应的最可能途径。
Polystyrene-supported Pd(II) complex-catalysed carboacylation of 2-arylpyridines with alcohols via C─H bond activation under solvent-free conditions
作者:Pullaiah C. Perumgani、Sai Prathima Parvathaneni、Srinivas Keesara、Mohan Rao Mandapati
DOI:10.1002/aoc.3581
日期:2017.3
was used as an efficientcatalyst for the synthesis of aromatic ketones via ortho‐acylation of sp2 C─H bonds of 2‐arylpyridines with alcohols as effective coupling partners. The alcohols were oxidized with tert‐butyl hydroperoxide to their corresponding aldehydes in situ and efficiently coupled with 2‐arylpyridines to form aryl ketones undersolvent‐free conditions. Furthermore, catalyst C could be easily