Recent Advances in the Catalytic Synthesis of 1,3-Diamines

1,3-Diamines are important for many biologically active molecules, but there have been fewer studies on the synthesis of 1,3-diamines than those on the synthesis of 1,2-diamines. Relatively speaking, there are not sufficient reports on non-catalytic methods in this direction. Among various methods, the catalytic construction of diamine products from nitrogen-containing substrates is the most straightforward, but it suffers from the need to pre-synthesize nitrogen-containing substrates and is therefore narrowly used. For non-specialized substrates, the direct construction of C-N bonds by metal- or non-metal-catalyzed C-H functionalization is undoubtedly the most efficient approach. This method is currently focused on monofunctionalization, but less has been reported for the simultaneous construction of multiple C-N bonds. Here, we summarize some innovative methods for the synthesis of 1,3-diamines that have been developed in the past five years, encompassing various directions such as non-catalytic reaction and metal- or non-metal catalyzed reaction.