title: Porphothionolactones: synthesis, structure, physical, and chemical properties of a chemodosimeter for hypochlorite.
abstract: The conversion of the lactone functionality of porpholactones, porphyrin analogs in which a porphyrin β,β'-double bond was replaced by a lactone moiety, to a thionolactone functionality using Lawesson's reagent is described. The resulting novel thionolactones were spectroscopically characterized and their electronic structure defined using experimental (UV-vis, fluorescence, cyclic voltammetry) and theoretical methods (molecular modelling at the B3LYP/6-31G(d) level). The structures of two benchmark thionolactones were determined by single crystal X-ray diffractometry. The idealized planarity of the chromophores rationalize the bathochromically shifted optical spectra of the thionolactones when compared to the lactones on electronic grounds. The thionolactone moiety can be used as a synthetic handle in the preparation of oxazolochlorins using RANEY® nickel-induced hydrodesulfurization reactions. Importantly, the meso-pentafluorophenyl-based porphothionolactone fluoresces by at least a factor of 60 less compared to the corresponding lactone. The hypochlorite-selective conversion of the thionolactone to the lactone is the basis for the use of this thionolactone as a switch-on chemodosimeter for hypochlorite, a widely used disinfectant and molecule of biological significance in some inflammatory processes.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, ChengFu Road 202, Beijing 100871, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yu
authors.forename: Brigitte
authors.initials: B
authors.lastname: Czepukojc
authors.forename: Claus
authors.initials: C
authors.lastname: Jacob
authors.forename: Yue
authors.initials: Y
authors.lastname: Jiang
authors.forename: Matthias
authors.initials: M
authors.lastname: Zeller
authors.forename: Christian
authors.initials: C
authors.lastname: Brückner
authors.forename: Jun-Long
authors.initials: JL
authors.lastname: Zhang
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D060326:Chemistry Techniques, Synthetic; D018360:Crystallography, X-Ray; D004202:Disinfectants / Q000032:analysis / Q000737:chemistry; D004563:Electrochemistry; D004583:Electrons; D006997:Hypochlorous Acid / Q000032:analysis* / Q000737:chemistry*; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D055585:Physical Phenomena; D011166:Porphyrins / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D004202:Disinfectants; D007783:Lactones; D011166:Porphyrins; D006997:Hypochlorous Acid