Selective hydrogenation of cinnamaldehyde (CAL) is an important reaction because the main products, cinnamic alcohol (COL) and hydrocinnamaldehyde (HCAL), are used in various fields, such as production of pharmaceutical intermediates, chemicals, perfumes, and fragrances. In recent years, numerous metal-based catalysts and significant study achievements have been reported. Thus, this Review focuses on selective hydrogenation of CAL to target products in terms of metal-based catalysts and summarizes recent developments in this reaction with different catalysts, including Pt-, Pd-, Ru-, Ni-, Co-, and Cu-based catalysts. In addition, the reaction mechanisms of different catalysts, the effects of catalyst substrates, the different catalyst structures, and the synergistic effects in bimetallic catalysts are discussed. Lastly, the limitations and barriers encountered for noble metal and non-noble metal catalysts in the current study as well as potential research trends are discussed.

中文翻译：

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负载型金属基催化剂上肉桂醛选择性加氢的新进展

肉桂醛（CAL）的选择性加氢是重要的反应，因为主要产品肉桂醇（COL）和氢肉桂醛（HCAL）已用于各种领域，例如医药中间体，化学品，香料和香料的生产。近年来，已经报道了许多金属基催化剂和重要的研究成果。因此，本综述着重于将CAL选择性氢化为目标产物（基于金属的催化剂），并总结了使用不同催化剂（包括Pt-，Pd-，Ru-，Ni-，Co-和Cu-）进行的该反应的最新进展。碱催化剂。此外，还讨论了不同催化剂的反应机理，催化剂底物的影响，催化剂结构的不同以及双金属催化剂的协同作用。最后，