Pain Tanmoy, Singh Ajit Kumar, Tarai Arup, Mondal Sruti, Indra Arindam, Kar Sanjib
School of Chemical Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar 752050, India.
Training School Complex, Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India.
Inorg Chem. 2023 Nov 20;62(46):18779-18788. doi: 10.1021/acs.inorgchem.3c02778. Epub 2023 Nov 7.
A new class of antimony(III) corroles has been described. The photophysical properties of these newly synthesized tetrakis(thiocyano)corrolatoantimony(III) derivatives having four SCN groups on the bipyrrole unit of corrole are drastically altered compared to their β-unsubstituted corrolatoantimony(III) analogues. The UV-vis and emission spectra of tetrakis(thiocyano)corrolatoantimony(III) derivatives are significantly red-shifted (roughly 30-40 nm) in comparison with their β-unsubstituted corrolatoantimony(III) derivatives. The Q bands are significantly strengthened. The intensity of the most prominent Q band is roughly 70% that of the Soret band and absorbs strongly at the far-red region, i.e., at 700-720 nm. These molecules emit light in the near-infrared region (700-900 nm). Tetrakis(thiocyano)corrolatoantimony(III) undergoes electrochemical anodic oxidation to form Sb═O species, which facilitates electrocatalytic oxygen evolution reaction (OER) and the activation of benzylic C-H to produce benzoic acid selectively. Under optimized conditions, Sb-corrole@NF (NF = nickel foam) required an overpotential of 380 mV to reach a 50 mA cm current density, comparable with those of other transition-metal-based complexes. On the other hand, replacing the anodic OER with benzyl alcohol oxidation lowered the required potential by 150 mV (at 300 mA cm) to improve the energy efficiency of the electrochemical process.
已描述了一类新型的锑（III）卟啉化合物。与它们的β-未取代卟啉锑（III）类似物相比，这些在卟啉的联吡咯单元上具有四个硫氰基的新合成的四（硫氰基）卟啉锑（III）衍生物的光物理性质发生了显著变化。四（硫氰基）卟啉锑（III）衍生物的紫外可见光谱和发射光谱与它们的β-未取代卟啉锑（III）衍生物相比有明显的红移（约30-40nm）。Q带显著增强。最突出的Q带强度约为Soret带的70%，并在远红外区域（即700-720nm）有强烈吸收。这些分子在近红外区域（700-900nm）发光。四（硫氰基）卟啉锑（III）发生电化学阳极氧化形成Sb═O物种，这促进了电催化析氧反应（OER）以及苄基C-H的活化，从而选择性地生成苯甲酸。在优化条件下，Sb-卟啉@NF（NF =泡沫镍）达到50 mA cm电流密度需要380 mV的过电位，与其他基于过渡金属的配合物相当。另一方面，用苄醇氧化代替阳极OER可将所需电位降低150 mV（在300 mA cm时），以提高电化学过程的能量效率。
