Matienko Ludmila I, Mil Elena M, Albantova Anastasia A, Goloshchapov Alexander N
N.M. Emanuel Institution of Biochemical Physics Russian Academy of Science, 4 Kosygin Str., 119334 Moscow, Russia.
Int J Mol Sci. 2025 Jan 29;26(3):1166. doi: 10.3390/ijms26031166.
It is known that the presence of redox-inactive metals in the active center of an enzyme has a significant effect on its activity. In this regard and for other reasons, the effect of redox-inactive metals on redox processes, such as electron transfer, oxygen and hydrogen atom transfer, as well as the breaking and formation of O-O bonds in reactions catalyzed by transition metals, has been widely studied. Many questions about the role of redox-inactive metals in the mechanisms of these reactions remain open. In this paper, the mechanism of catalysis by bi- and triple hetero-binuclear heteroligand complexes including Ni and redox-inactive alkali metals ((A) {Ni(acac)∙L} and (B) {Ni(acac)∙L∙PhOH} (L = MSt (M = Li, Na, or K)) in the process of the selective oxidation of ethylbenzene by molecular oxygen into α-phenyl ethyl hydroperoxide is considered. The activity of A and B complexes towards O, ROOH, and RO radicals was studied. Based on kinetic data, we suggest that the high catalytic efficiency of B triple complexes in oxidation processes may be associated with the role of outer-sphere regulatory interactions, with the formation of stable supramolecular structures due to intermolecular H bonds. This assumption was confirmed using the AFM method. Prospects for studying catalysis by complexes ({Ni(acac)∙L} and {Ni(acac)∙L∙PhOH}) that are models of NiARD (Ni-Acyreductone dioxygenase) are discussed.
已知酶活性中心中氧化还原惰性金属的存在对其活性有显著影响。基于这一点及其他原因，氧化还原惰性金属对氧化还原过程的影响，如电子转移、氧和氢原子转移，以及过渡金属催化反应中O - O键的断裂和形成，已得到广泛研究。关于氧化还原惰性金属在这些反应机制中的作用仍有许多问题有待解决。本文考虑了包含镍和氧化还原惰性碱金属的双和三杂双核异配体配合物（(A) {Ni(acac)∙L} 和 (B) {Ni(acac)∙L∙PhOH} (L = MSt (M = Li、Na或K))）在分子氧将乙苯选择性氧化为α - 苯基乙基氢过氧化物过程中的催化机制。研究了A和B配合物对O、ROOH和RO自由基的活性。基于动力学数据，我们认为B三配合物在氧化过程中的高催化效率可能与外层调节相互作用的作用有关，即由于分子间氢键形成稳定的超分子结构。这一假设通过原子力显微镜方法得到了证实。讨论了研究作为NiARD（镍 - 酰基还原酮双加氧酶）模型的配合物（{Ni(acac)∙L} 和 {Ni(acac)∙L∙PhOH}）催化作用的前景。
