Mn(III) active site in hydrotalcite efficiently catalyzes the oxidation of alkylarenes with molecular oxygen was written by Wang, Anwei;Zhou, WeiYou;Sun, Zhonghua;Zhang, Zhong;Zhang, Zhihui;He, MingYang;Chen, Qun. And the article was included in Molecular Catalysis in 2021.Reference of 91-02-1 This article mentions the following:
Developing efficient heterogeneous catalytic systems based on easily available materials and mol. oxygen for the selective oxidation of alkylarenes is highly desirable. In the present research, NiMn hydrotalcite (Ni2Mn-LDH) was found as an efficient catalyst in the oxidation of alkylarenes using mol. oxygen as the sole oxidant without any additive. Impressive catalytic performance, excellent stability and recyclability, broad applicable scope and practical potential for the catalytic system were observed Mn3+ species is proposed to be the efficient active site, and Ni2+ played an important role in stabilizing the Mn3+ species in the hydrotalcite structure. The kinetic study showed that the aerobic oxidation of diphenylmethane is a first-order reaction over Ni2Mn-LDH with the activation energy (Ea) and pre-exponential factor (A0) being 85.7 kJ mol-1 and 1.8 x 109 min-1, resp. The Gibbs free energy (ΔG≠) is -10.4 kJ mol-1 K-1 for the oxidation based on Eyring-Polanyi equation, indicating the reaction is exergonic. The mechanism study indicated that the reaction proceeded through both radical and carbocation intermediates. The two species were then trapped by mol. oxygen and H2O or hydroxyl species, resp., to yield the corresponding products. The present research might provide information for constructing highly efficient and stable active site for the catalytic aerobic oxidation based on available and economic material. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Reference of 91-02-1).
Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals.Reference of 91-02-1