Keshari Kritika, Santra Aakash, Velasco Lucía, Sauvan Maxime, Kaur Simarjeet, Ugale Ashok D, Munshi Sandip, Marco J F, Moonshiram Dooshaye, Paria Sayantan
Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Sor Juana Inés de la Cruz, 3, Madrid 28049, Spain.
JACS Au. 2024 Mar 11;4(3):1142-1154. doi: 10.1021/jacsau.3c00844. eCollection 2024 Mar 25.
Herein, we show that the reaction of a mononuclear Fe(OH) complex () with -tosyliminobenzyliodinane (PhINTs) resulted in the formation of a Fe(OH) species (). The obtained complex was characterized by an array of spectroscopic techniques and represented a rare example of a synthetic Fe(OH) complex. The reaction of with the one-electron oxidizing agent was reported to form a ligand-oxidized Fe(OH) complex (). revealed a one-electron reduction potential of -0.22 V vs Fc/Fc at -15 °C, which was 150 mV anodically shifted than ( = -0.37 V vs Fc/Fc at -15 °C), inferring to be more oxidizing than . reacted spontaneously with (4-OMe-CH)C to form (4-OMe-CH)C(OH) through rebound of the OH group and displayed significantly faster reactivity than . Further, activation of the hydrocarbon C-H and the phenolic O-H bond by and was compared and showed that is a stronger oxidant than . A detailed kinetic study established the occurrence of a concerted proton-electron transfer/hydrogen atom transfer reaction of . Studying one-electron reduction of and using decamethylferrocene (Fc*) revealed a higher of than . The study established that the primary coordination sphere around Fe and the redox state of the metal center is very crucial in controlling the reactivity of high-valent Fe-OH complexes. Further, a Fe(OMe) complex () was synthesized and thoroughly characterized, including X-ray structure determination. The reaction of with PhINTs resulted in the formation of a Fe(OMe) species (), revealing the presence of two Fe species with isomer shifts of -0.11 mm/s and = 0.17 mm/s in the Mössbauer spectrum and showed Fe/Fe potential at -0.36 V vs Fc/Fc couple in acetonitrile at -15 °C. The reactivity studies of were investigated and compared with the Fe(OH) complex ().
在此,我们表明单核Fe(OH)配合物()与对甲苯磺酰亚胺苄碘(PhINTs)的反应导致形成了一种Fe(OH)物种()。所得到的配合物通过一系列光谱技术进行了表征,代表了一种罕见的合成Fe(OH)配合物实例。据报道,与单电子氧化剂反应形成了一种配体氧化的Fe(OH)配合物()。在-15°C下,相对于Fc/Fc,显示出-0.22 V的单电子还原电位,比(在-15°C下相对于Fc/Fc为-0.37 V)向阳极移动了150 mV,这表明比氧化性更强。与(4-OMe-CH)C自发反应,通过OH基团的反弹形成(4-OMe-CH)C(OH),并且显示出比显著更快的反应活性。此外,比较了和对烃类C-H键和酚类O-H键的活化作用,结果表明是比更强的氧化剂。一项详细的动力学研究确定了发生了协同质子-电子转移/氢原子转移反应。使用十甲基二茂铁(Fc*)研究和的单电子还原,结果表明的比更高出。该研究确定,Fe周围的初级配位球和金属中心的氧化还原状态对于控制高价Fe-OH配合物的反应活性非常关键。此外,合成并全面表征了一种Fe(OMe)配合物(),包括X射线结构测定。与PhINTs的反应导致形成一种Fe(OMe)物种(),在穆斯堡尔谱中显示出两种具有-0.11 mm/s和 = 0.17 mm/s的同质异能位移的Fe物种,并且在-15°C的乙腈中相对于Fc/Fc电对显示出-0.36 V的Fe/Fe电位。研究了的反应活性,并与Fe(OH)配合物()进行了比较。