Decomposition of N-cyclopropyl-N-nitrosourea in the presence of reducing agents as a new way of generating the cyclopropyl radical

A new way of generating cyclopropyl radicals in the base-catalyzed decomposition of N-cyclopropyl-N-nitrosourea in the presence of organic reducing agents (1-phenylpyrazolidin-3-one and 4-methoxyphenol) was developed. The cyclopropyl radical generated under these conditions can not only abstract a proton from the substrate to give cyclopropane but also form C-C or C-Br bonds in reactions with aromatic substrates or polybromomethanes.