A general, electrocatalytic approach to the synthesis of vicinal diamines

This protocol describes an electrochemical synthesis of 1,2-diazides from alkenes. Organic azides are highly versatile intermediates for synthetic chemistry, materials, and biological applications. 1,2-Diazides are commonly reduced to form 1,2-diamines, which are prevalent structural motifs in bioactive natural products, therapeutic agents, and molecular catalysts. The electrochemical formation of 1,2-diazides involves the anodic generation of an azidyl radical from sodium azide, followed by two successive additions of this N-centered radical to the alkene, and is assisted by a Mn catalyst. The electrosynthesis of 1,2-diazides can be carried out using various experimental setups comprising custom-made or commercially available reaction vessels and a direct-current power supply. Readily accessible electrode materials can be used, including carbon (made from reticulated vitreous carbon and pencil lead), nickel foam, and platinum foil. This protocol is also demonstrated using ElectraSyn, a standardized electrochemistry kit. Compared with conventional synthetic approaches, electrochemistry allows for the precise control of the anodic potential input, eliminates the need for stoichiometric and often indiscriminate oxidants, and minimizes the generation of wasteful byproducts. As such, our electrocatalytic synthesis exhibits various advantages over existing methods for alkene diamination, including sustainability, operational simplicity, substrate generality, and exceptional functional-group compatibility. The resultant 1,2-diazides can be smoothly reduced to 1,2-diamines in a single step with high chemoselectivity. To exemplify this, we include a procedure for catalytic hydrogenation using palladium on carbon. This protocol, therefore, constitutes a general approach to accessing 1,2-diazides and 1,2-diamines from alkenes.