title: Photoinduced Carbon Monoxide Release from Half-Sandwich Iron(II) Carbonyl Complexes by Visible Irradiation: Kinetic Analysis and Mechanistic Investigation.
abstract: Three half-sandwich iron(II) complexes, [Fe(η(5) -Cp)(cis-CO)2 X] (X(-) =Cl(-) , Br(-) , I(-) ), were synthesized and characterized. The kinetics of the CO-releasing behaviour of these complexes upon illumination by visible irradiation in various media was investigated. Our results indicated that the CO release was significantly affected by the auxiliary ligands. Of the three light sources used (blue, green, and red), blue light exhibited the highest efficiency. In the photoinduced CO release, the solvents and exogenous nucleophiles in the media were involved, which allowed their CO-releasing reaction to comply with pseudo first-order model rather than the characteristic zero-order model for a photochemical reaction. In aqueous media (D2 O), an intermediate bearing the core of {Fe(II) (cis-CO)2 } involving cleavage of cyclopentadiene was detected. Despite the non-absorption of the red light, its illumination combined with nucleophilic substitution did cause considerable CO release. Assessment of the cytotoxicity of the three complexes indicated that they showed good biocompatibility.
authors.affiliation: College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing (P. R. China), Fax: (+86) 573-8364-3937.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Jiang
authors.affiliation: School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou (P. R. China).
authors.forename: Limei
authors.initials: L
authors.lastname: Chen
authors.affiliation: College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing (P. R. China), Fax: (+86) 573-8364-3937.
authors.forename: Xiu
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing (P. R. China), Fax: (+86) 573-8364-3937.
authors.forename: Li
authors.initials: L
authors.lastname: Long
authors.affiliation: College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing (P. R. China), Fax: (+86) 573-8364-3937.
authors.forename: Zhiyin
authors.initials: Z
authors.lastname: Xiao
authors.affiliation: College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing (P. R. China), Fax: (+86) 573-8364-3937. xiaoming.liu@mail.zjxu.edu.cn.|School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou (P. R. China). xiaoming.liu@mail.zjxu.edu.cn.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
keywords: anions; carbon monoxide; carbonyl complexes; iron; photoinduction