Iron-catalysed radical Markovnikov hydroamidation of complex alkenes

Abstract

Nitrogen atoms are integral components of various chemical functional groups, including amines, amides and N-heterocycles, among others. Consequently, they play an important role in pharmaceuticals, agrochemicals, natural products, materials and commodity chemicals. The formation of C–N bonds is reliably achieved through methods, such as reductive amination, N-alkylation and cross-coupling. Hydroamination, starting with alkenes, presents a valuable alternative for accessing organic compounds containing nitrogen, as alkenes are highly abundant. Here we present a method for the iron-catalysed radical hydroamidation of alkenes. To this end, we developed a radical amidation reagent that can be readily prepared on a large scale, facilitating the efficient transfer of the synthetically valuable cyanamide functionality across both activated and unactivated double bonds. The scope of the reaction is remarkably broad, demonstrating its applicability to the diastereoselective hydroamidation of complex terpene natural products. Importantly, the synthesis of 15N-labelled amines is possible using this strategy. Subsequent chemistry, converting the distinctive cyanamide functionality into other useful groups, further validates the value of the developed methodology. An iron-catalysed radical Markovnikov hydroamidation of alkenes using a cyanamide reagent is reported. The method achieves C–N bond formation with high yields and selectivity and is applicable to a wide range of alkenes and natural products. The cyanamide functionality can be transformed into various functional groups, highlighting its potential for advanced applications in natural product synthesis.