Abstract A simple and efficient method for preparation of imines by the oxidative coupling of benzyl alcohols with aromatic amines or aliphatic amines was developed. The reaction was catalyzed by 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO)/KOH with air as the economic and green oxidant. Under the optimal reaction conditions, a variety of imines were obtained in 80%-96% isolated yields.
A process for preparing 3-[(S)-7-bromo-2-(2-oxo-propylamino)-5-pyridin-2-yl-3H-1,4,-benzodiazepin-3-yl]propionic acid methyl ester at a high conversion rate with good reproducibility by oxidizing 3-[(S)-7-bromo-2-(2-hydroxy-propylamino)-5-pyridin-2-yl-3H-benzo[e][1,4]diazepin-3-yl]propionic acid methyl ester in the presence of an oxidation catalyst is provided by defining the ammonium ion content of 3-[(S)-7-bromo-2-(2-hydroxy-propylamino)-5-pyridin-2-yl-3H-benzo[e][1,4]diazepin-3-yl]propionic acid methyl ester.
A new transition-metal-free 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO) catalyzed aerobic oxidative synthesis of 2-substituted 4H-3,1-benzoxazines and quinazolines has been developed through cascade reaction of aldehydes with 2-aminobenzyl alcohols and 2-aminobenzylamines, respectively. Under the optimal reaction conditions, the two kinds of heterocycles were obtained in 72–97 % isolated yield.
Revisiting the Electrochemistry of TEMPOH Analogues in Acetonitrile
作者:Xiao Zhao、Jin-Dong Yang、Jin-Pei Cheng
DOI:10.1021/acs.joc.2c02537
日期:2023.1.6
experimentally observed facile oxidation of TEMPOH. Herein, the electrochemistry of TEMPOH derivatives in acetonitrile was revisited, featuring much smaller oxidation potentials (about 0 V) than literature ones. Acid/base effects and kinetic studies lent credibility to these new values. Such a 0.7 V energy discrepancy impelled us to review the thermodynamic properties and oxidation mechanisms of TEMPOH deduced
以 1-羟基-2,2,6,6-四甲基哌啶 (TEMPOH) 为代表的羟胺作为活性物质广泛参与各种化学和电化学氧化。TEMPOH 的电化学行为对于理解 TEMPO 介导的氧化还原序列的机制至关重要。然而,与对水溶液中 TEMPOH 电化学的大量研究相比,其氧化电位E ox的唯一值据报道,有机溶液中的 (TEMPOH) 为 0.7 V(相对于乙腈中的 Fc),这似乎与实验观察到的 TEMPOH 容易氧化相矛盾。在此,重新研究了 TEMPOH 衍生物在乙腈中的电化学,其氧化电位(约 0 V)比文献中的小得多。酸/碱效应和动力学研究为这些新值提供了可信度。这种 0.7 V 的能量差异促使我们重新审视从旧值推导出的 TEMPOH 的热力学性质和氧化机制。
Class Ib Ribonucleotide Reductases: Activation of a Peroxido-Mn<sup>II</sup>Mn<sup>III</sup> to Generate a Reactive Oxo-Mn<sup>III</sup>Mn<sup>IV</sup> Oxidant
作者:Lorna Doyle、Adriana Magherusan、Shuangning Xu、Kayleigh Murphy、Erik R. Farquhar、Florian Molton、Carole Duboc、Lawrence Que、Aidan R. McDonald
DOI:10.1021/acs.inorgchem.3c04163
日期:2024.1.29
(p-TsOH) or (μ-O)2MnIIIMnIV (4) upon warming to roomtemperature. The physical properties of 3 and 4 were probed using UV–vis, EPR, X-ray absorption, and IR spectroscopies and mass spectrometry. Compounds 3 and 4 were capable of phenol oxidation to yield a phenoxyl radical via a concerted PCET oxidation, supporting the proposed mechanism of tyrosyl radical cofactor generation in RNRs. The synthetic models