A novel transition metal free [bis-(trifluoroacetoxy)iodo]benzene (PIFA) mediated oxidative ipso nitration of organoboronic acids†
Abstract
A mild, convenient and transition metal free methodology for oxidative ipso nitration of diversely functionalized organoboronic acids, including heteroaryl- and alkylboronic acids, has been developed at ambient temperature using a combination of [bis-(trifluoroacetoxy)]iodobenzene (PIFA) – N-bromosuccinimide (NBS) and sodium nitrite as the nitro source. It is anticipated that the reaction proceeds through in situ generation of NO2 and O-centred organoboronic acid radicals followed by the formation of an O–N bond via combination of the said radicals. Finally transfer of the NO2 group to the aryl moiety occurs through 1,3-aryl migration to provide the nitroarenes.