title: Remarkably stable iron porphyrins bearing nonheteroatom-stabilized carbene or (alkoxycarbonyl)carbenes: isolation, X-ray crystal structures, and carbon atom transfer reactions with hydrocarbons.
abstract: Reactions of [Fe(TPFPP)] (TPFPP = meso-tetrakis(pentafluorophenyl)porphyrinato dianion) with diazo compounds N(2)C(Ph)R (R = Ph, CO(2)Et, CO(2)CH(2)CH=CH(2)) afforded [Fe(TPFPP)(C(Ph)R)] (R = Ph (1), CO(2)Et (2), CO(2)CH(2)CH=CH(2) (3)) in 65-70% yields. Treatment of 1 with N-methylimidazole (MeIm) gave the adduct [Fe(TPFPP)(CPh(2))(MeIm)] (4) in 65% yield. These new iron porphyrin carbene complexes were characterized by NMR and UV-vis spectroscopy, mass spectrometry, and elemental analyses. X-ray crystal structure determinations of 1.0.5C(6)H(6).0.5CH(2)Cl(2) and 4 reveal Fe=CPh(2) bond lengths of 1.767(3) (1) and 1.827(5) A (4), together with large ruffling distortions of the TPFPP macrocycle. Complexes 2 and 4 are reactive toward styrene, affording the corresponding cyclopropanes in 82 and 53% yields, respectively. Complex 1 is an active catalyst for both intermolecular cyclopropanation of styrenes with ethyl diazoacetate and intramolecular cyclopropanation of allylic diazoacetates. Reactions of 2 and 4 with cyclohexene or cumene produced allylic or benzylic C-H insertion products in up to 83% yield.
authors.affiliation: Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Jie-Sheng
authors.initials: JS
authors.lastname: Huang
authors.forename: Zhong-Yuan
authors.initials: ZY
authors.lastname: Zhou
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Che
authors.forename: Xiao-Zeng
authors.initials: XZ
authors.lastname: You
mesh_terms: D002244:Carbon / Q000737:chemistry; D018360:Crystallography, X-Ray; D005290:Ferric Compounds / Q000737:chemistry; D006838:Hydrocarbons / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008665:Metalloporphyrins / Q000737:chemistry; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000302:isolation & purification; D008958:Models, Molecular; D015394:Molecular Structure; D011166:Porphyrins / Q000737:chemistry* / Q000302:isolation & purification; D005464:Fluorobenzenes; D005466:Fluorocarbons
chemical_list: D002244:Carbon; D005290:Ferric Compounds; D006838:Hydrocarbons; D007501:Iron; D008665:Metalloporphyrins; D008697:Methane; D011166:Porphyrins; C093411:tetrakis(pentafluorophenyl)porphyrinato iron(III) chloride; D005464:Fluorobenzenes; D005466:Fluorocarbons; C030011:carbene