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Principles for safe operation of catalytic hydrogenation reactions: 1. Catalyst should be obtained according to the actual needs. Take as much as is needed, and avoid taking too much at once, as this could lead to a decrease in the catalyst’s activity or even its deactivation, as well as drying out and loss of moisture or even spontaneous combustion. Temporary storage must be under nitrogen protection. 2. Inspection and use of instruments and equipment (1) When carrying out catalytic hydrogenation reactions in the laboratory, it is necessary to carefully inspect the instruments used before proceeding; glass instruments with obvious damage, cracks, or air bubbles must not be used ； (2) The hydrogen gas bags used must be checked for leaks using nitrogen; leaking hydrogen gas bags must not be used ； (3) Check whether the hoses used are aged and unusable, as well as whether the joints are loose ； For catalytic hydrogenation reactions carried out in an autoclave, specialized training must be provided to personnel before using the autoclave for the first time. Before using the equipment, it must be inspected item by item in accordance with the regulations. The main aspects to check include: (1) Whether the area is clean and organized, to avoid safety hazards caused by clutter ； (2) The pressure gauges for hydrogen and nitrogen must undergo a pressure test before use, and can only be employed after it is confirmed that they are functioning properly ； (3) Pressure of hydrogen and nitrogen cylinders ； (4) Are there any cracks in the pipeline, and is it unobstructed? ； (5) Check whether each valve is leaking air and confirm its open/close status ； (6) Check whether the thermocouple thermometer is in good working condition, whether the wiring is intact with no exposed electricity; when inserting the thermocouple, make sure to insert it fully to ensure an accurate reflection of the system’s temperature ； 3. Material addition: Add the solvent and raw materials to the container; after stirring to ensure dissolution, blow nitrogen into the container for a period of time to maintain an inert atmosphere in the system, then add the catalyst. The addition of the catalyst must be done quickly to minimize the possibility of the catalyst catching fire on its own and igniting the solvent. Alternatively, the catalyst can be added to the solvent first and then both combined and transferred into the reactor, followed by the addition of the main reactants; however, it is difficult to observe due to the black color of the system. Replacement system: After evacuating the air from the system using vacuum, nitrogen is introduced into it using a nitrogen tank; then the nitrogen is evacuated again. This process is repeated 3–5 times. After that, the nitrogen is once more evacuated, and hydrogen is introduced using a hydrogen tank. This step is repeated 2–3 times, and finally hydrogen is introduced to initiate the reaction. In an autoclave, a higher number of replacement cycles is required. 4. Sampling during the reaction: Before sampling, purge the system with nitrogen 2–3 times, or blow in nitrogen for a while before taking samples using a dropper (for sampling in an autoclave, nitrogen is used to push the sample out through the material feed port). 5. Post-treatment: After the reaction is complete, the system is purged with nitrogen to place it in an inert atmosphere. Filtration under vacuum is carried out, and the filter cake is washed 2–3 times with a solvent. It should then be sealed promptly with ethanol or water, and recovered as soon as possible. The used catalyst still retains high activity, and the presence of residual solvents may also lead to spontaneous combustion; therefore, care should be taken during handling. 6. Clean up the site: After the reaction is complete, clean the area promptly; debris such as absorbent paper coated with palladium carbon must be disposed of properly. Debris containing a large amount of palladium on carbon must be wetted with water and removed promptly.