Designing a Potential Pathway for the Catalytic Synthesis of 1,3-Cyclohexanediamine

Cyclohexylamines are important and valuable key intermediates in the chemical industry, playing a crucial role in the synthesis of a variety of compounds. Developing a low-cost and efficient synthesis route for these chemicals is highly desirable but also presents significant challenges due to the complexity of the reactions involved. Herein, we designed three pathways for the production of 1,3-cyclohexanediamine (1,3-CHDA), including the one-pot reductive amination of resorcinol (RES) with ammonia and molecular hydrogen, the reductive amination of 1,3-cyclohexandione (1,3-CHD) with ammonia, and the oximation–hydrogenation of 1,3-CHD. Through systematical investigation, we finally developed a low-cost, simple operation and an efficient methodology for the synthesis of 1,3-CHDA as follows: RES was firstly hydrogenated in H2O over Raney Ni to obtain 1,3-CHD, and then the obtained liquid reaction mixture was used directly for the subsequent oximation with hydroxylamine hydrochloride without further purification to form the oxime intermediate, followed by the hydrogenation of the oxime in methanol over Raney Ni to achieve the target product 1,3-CHDA with a high yield.