1,3‐Di(2‐pyrrolyl)azulene: An Efficient Luminescent Probe for Fluoride

Abstract

Photo‐induced Energy Transfer (PET) based chemosensing is a very elegant way for reporting the presence of an analyte in solution. This method was successfully applied to the detection of many cationic species in solutions and already appears in interesting commercial applications. In this paper we report on the preparation and host–guest chemistry of 1,3‐di(2‐pyrrolyl)azulene (5), a new azulene‐based selective PET‐like chemosensor that turns fluorescent upon binding the fluoride anion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Metalated heterocycles in organic synthesis: Recent applications

“…Subsequent double Stille coupling with dibrominated azulene 171 gave the bis(pyrrolyl)azulene 172, which, once deprotected, is an efficient luminescent probe for fluoride. 326 When 3-stannylated pyrrole are desired, a halogen-lithium exchange is usually performed, a recent example being the preparation and use of a 3-trimethylstannylated Ntosylated pyrrole in the generation of a stannylated Diels-Alder adduct for a copper-promoted trimerization. …”

Metalated Heterocycles in Organic Synthesis: Recent Applications

“…Subsequent double Stille coupling with dibrominated azulene 171 gave the bis(pyrrolyl)azulene 172, which, once deprotected, is an efficient luminescent probe for fluoride. 326 When 3-stannylated pyrrole are desired, a halogen-lithium exchange is usually performed, a recent example being the preparation and use of a 3-trimethylstannylated Ntosylated pyrrole in the generation of a stannylated Diels-Alder adduct for a copper-promoted trimerization. 327 …”

Azulene–boronate esters: colorimetric indicators for fluoride in drinking water

“…[33][34][35] (Some of these indicators are not wholly selective and also exhibit a colorimetric response to fluoride [27][28][29][30] ). Of closest relevance to our present work is a report from Eichen et al 36 which describes a fluorescent azulene-based fluoride sensor that also exhibits a colorimetric response (green to violet) in DMSO. To our knowledge, there are no published reports of azulene-boronate colorimetric fluoride indicators.…”