title: 4-Chloro-2-fluoro-5-nitrobenzoic acid as a possible building block for solid-phase synthesis of various heterocyclic scaffolds.
abstract: 4-Chloro-2-fluoro-5-nitrobenzoic acid is a commercially available multireactive building block that can serve as a starting material in heterocyclic oriented synthesis (HOS) leading to various condensed nitrogenous cycles. This work describes its ability for the preparation of substituted nitrogenous heterocycles having 5-7-membered cycles via polymer-supported o-phenylendiamines. Immobilization of this compound on Rink resin followed by further chlorine substitution, reduction of a nitro group and appropriate cyclization afforded benzimidazoles, benzotriazoles, quinoxalinones, benzodiazepinediones and succinimides. The method developed is suitable for the synthesis of diverse libraries including the mentioned types of heterocycles, which have significant importance in current drug discovery. In this paper, we also report limitation of these method and unsuccessful attempt to prepare an 8-membered benzodiazocine cycle.
authors.affiliation: Institute of Molecular and Translational Medicine, Department of Organic Chemistry, Faculty of Science, Palacky University, 17 Listopadu 12, 771 46 Olomouc, Czech Republic.
authors.forename: Soňa
authors.initials: S
authors.lastname: Křupková
authors.forename: Petr
authors.initials: P
authors.lastname: Funk
authors.forename: Miroslav
authors.initials: M
authors.lastname: Soural
authors.forename: Jan
authors.initials: J
authors.lastname: Hlaváč
mesh_terms: D002384:Catalysis; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D015394:Molecular Structure; D009579:Nitrobenzoates / Q000737:chemistry*; D060327:Solid-Phase Synthesis Techniques
chemical_list: C000591079:4-chloro-2-fluoro-5-nitrobenzoic acid; D006571:Heterocyclic Compounds; D009579:Nitrobenzoates