A metal- and base-free
method is developed for the synthesis of aryl iodides from arylhydrazine
hydrochlorides and iodine. A wide variety of aryl iodides can be conveniently
synthesized by an equimolar reaction of arylhydrazine hydrochlorides
and I
2
in dimethyl sulfoxide at 60 °C for 6 h. In
the iodination step, arylhydrazines are oxidized by iodine to form
arenediazonium salts, which undergo single-electron transfer from
iodide anion to give aryl and iodine radicals; subsequent combination
of them affords the corresponding aryl iodides.
Despite the promising pharmacological activity and material properties of five-membered heterocyclic compounds containing phosphorus and nitrogen, synthetic examples of them have been rather limited due to the instability of phosphorus toward air and water. In this study, 1,3-benzoazaphosphol analogues were selected as target molecules, and various synthetic routes were examined to establish a fundamental technology for the introduction of phosphorus groups into aromatic rings and formation of five-membered rings containing phosphorus and nitrogen by cyclization. As a result, we found that 2-aminophenyl(phenyl)phosphine is an extremely promising synthetic intermediate with high stability and easy handling. Furthermore, 2-methyl-3-phenyl-2,3-dihydro-1H-benzo[d][1,3]azaphosphole and 3-phenyl-2,3-dihydro-1H-benzo[d][1,3]azaphosphole-2-thione as synthetically useful 1,3-benzoazaphosphol analogues were successfully synthesized by using 2-aminophenyl(phenyl)phosphine as a key intermediate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.