1 Supporting Information Evidence for the formation of a mononuclear ferric-hydroperoxo complex via the reaction of dioxygen with an (N 4 S(thiolate))iron(II) complex Yunbo Jiang, a Joshua Telser b and David P. Goldberg* a a Department of Chemistry, Johns Hopkins University, Baltimore, Maryland, 21218, USA b Chemistry Program, Roosevelt University, Chicago, IL 60605 USA Contact Information Professor David P. Goldberg Department of Chemistry Johns Hopkins University, Baltimore, Maryland, 21218, USA Tel: 410-516-6658 Fax: 410-516-8420 E-mail:dpg@jhu.edu Supplementary Material (ESI) for Chemical Communications This journal is (c) The Royal Society of Chemistry 2009