Jana Narayan Ch, Herchel Radovan, Bagh Bidraha
School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, PO Bhimpur-Padanpur, Via Jatni, Khurda, Bhubaneswar 752050, Odisha, India.
Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. listopadu 12, 77146 Olomouc, Czech Republic.
Inorg Chem. 2024 Oct 7;63(40):18615-18631. doi: 10.1021/acs.inorgchem.4c02344. Epub 2024 Sep 26.
Four air-stable one-dimensional copper(II) coordination polymers (-) with azide linkers were synthesized using tridentate NNS and NNN ligands. Single-crystal X-ray diffraction (XRD) analysis confirmed the molecular structures of , , and . In the presence of TEMPO, all four coordination polymers demonstrated effective catalytic activity for the selective aerobic oxidation of veratryl alcohol, a biomass model compound, under base-free conditions. exhibited the best catalytic efficiency. Oxidations were conducted at ambient temperature (40 °C) utilizing air as a sustainable oxidant. Selective oxidation of veratryl alcohol to veratraldehyde was also conducted in the presence of a catalytic amount of base (5 mol %), and enhanced reactivity was observed. The green solvents, acetone, and water, were used to maximize sustainability. The optimized reaction conditions were applied to broaden the substrate scope of various lignin model alcohols and substituted benzylic alcohols with wide electronic variability. exhibited high recyclability, consistently providing quantitative yields even after ten consecutive runs. The catalytic protocol demonstrated sustainability and environmental compatibility, as evidenced by a low -factor (4.29) and a high Eco-scale score (90). Based on experimental evidence and theoretical calculations, a plausible catalytic cycle was proposed. Finally, the sustainability credentials of the different optimized reaction protocols were evaluated using the CHEM21 green metrics toolkit.
使用三齿NNS和NNN配体合成了四种具有叠氮连接体的空气稳定的一维铜（II）配位聚合物（-）。单晶X射线衍射（XRD）分析证实了 、 和 的分子结构。在TEMPO存在下，所有四种配位聚合物在无碱条件下对生物质模型化合物藜芦醇的选择性好氧氧化均表现出有效的催化活性。 表现出最佳的催化效率。氧化反应在环境温度（40℃）下利用空气作为可持续氧化剂进行。在催化量的碱（5 mol%）存在下也进行了藜芦醇到藜芦醛的选择性氧化，并且观察到反应活性增强。使用绿色溶剂丙酮和水以实现最大程度的可持续性。将优化的反应条件应用于拓宽各种具有广泛电子变异性的木质素模型醇和取代苄醇的底物范围。 表现出高可回收性，即使在连续十次运行后仍始终提供定量产率。催化方案显示出可持续性和环境相容性，低 -因子（4.29）和高生态规模得分（90）证明了这一点。基于实验证据和理论计算，提出了一个合理的催化循环。最后，使用CHEM21绿色指标工具包评估了不同优化反应方案的可持续性资质。
