Fe(NO 3 ) 3 ·9H 2 O-mediated visible-light photocatalysis for the nitration of cyclobutanols: access to functionalized nitrocyclobutenes

A straightforward method for the synthesis of nitrocyclobutene derivatives from cyclobutanols with Fe(NO 3 ) 3 ·9H 2 O has been developed via a visible-light photocatalytic radical addition reaction.