Then, the diazo-containing alkyl radicals could be further trapped again by molecular oxygen (Fig. ) or H 2 O through radical-coupling or single electron transfer (SET) process followed by nucleophilic attack (Fig. ). If successful, it would unlock easy access to offer a conceptual complementary of diazomethylationbased difunctionalization of alkenes, namely, 1,2-hydroxyl-diazomethylation. Of course, this hypothesis faces several severe challenges, including intramolecular alkyl radical coupling (IARC) with diazomethyl moiety (Fig. -III) , intermolecular dimerization (IDM) of diazomethyl radicals (Fig. -IV), and other side reactions.