The transfer hydrogenation of furfural (FF) to furfuryl alcohol (FFA) via the Meerwein-Ponndorf-Verley (MPV) reduction reaction is a promising and appealing strategy for the valorization of biomass, in which designing high-efficiency and high-selectivity Lewis acid-base catalysts is the central task. Recently, zirconium-organic acid coordination catalysts have been broadly constructed, however, most of them contained a certain amount of Brønsted acid sites (BASs) in addition to Lewis acid-base sites (LABSs), which inevitably influenced the yield and selectivity of FFA. In this work, a zirconium-melamine coordination catalyst (Zr-MM) was synthesized by a convenient self-assembly process, in which melamine (MM) was used as a cheap organic ligand. Systematic experimental results indicated that Zr-MM possessed strong LABSs, and at the same time, lacked BASs, which could not only catalyze the transfer hydrogenation of FF and facilitate the formation of FFA, but also avoid the further transformation of FFA and improve the selectivity of FFA. Hence, it showed remarkable catalytic activity, leading to 100% FF conversion and 99.4% FFA yield in isopropanol at 150 °C for 4 h. More significantly, Zr-MM also displayed excellent catalytic stability and catalytic universality, and it could not only be reused for five reaction cycles without an apparent decrease in catalytic activity, but also be employed for the effective transfer hydrogenation of 5-methylfurfural, 5-hydroxymethylfurfural, phenylaldehyde, cyclohexanone, methyl levulinate and ethyl levulinate. All in all, this work provided some crucial references to prepare the BASs-free zirconium-based coordination catalysts for the upgradation of biomass-derived carbonyl compounds.

通过 Meerwein-Ponndorf-Verley (MPV) 还原反应将糠醛 (FF) 转移氢化为糠醇 (FFA) 是生物质增值的一种有前途且有吸引力的策略，其中设计高效和高选择性的路易斯酸碱催化剂是中心任务。近年来，锆-有机酸配位催化剂已被广泛构建，但大多数除路易斯酸碱位点（LABS）外还含有一定量的布朗斯台德酸位点（BAS），这不可避免地影响了FFA的产率和选择性。在这项工作中，通过方便的自组装工艺合成了锆-三聚氰胺配位催化剂（Zr-MM），其中三聚氰胺（MM）被用作廉价的有机配体。系统实验结果表明Zr-MM具有很强的LABSs，同时，缺少BAS，不仅可以催化FF的转移氢化，促进FFA的形成，而且可以避免FFA的进一步转化，提高FFA的选择性。因此，它表现出显着的催化活性，在异丙醇中150°C 4小时内FF转化率为100%，FFA产率为99.4%。更重要的是，Zr-MM还表现出优异的催化稳定性和催化普适性，不仅可以重复使用五个反应循环而催化活性没有明显下降，而且可以用于5-甲基糠醛、5-甲基糠醛、5-甲基糠醛的有效转移加氢。羟甲基糠醛、苯醛、环己酮、乙酰丙酸甲酯和乙酰丙酸乙酯。总而言之，