Dual Binding Site Assisted Chromogenic and Fluorogenic Recognition and Discrimination of Fluoride and Cyanide by a Peripherally Borylated Metalloporphyrin: Overcoming Anion Interference in Organoboron Based Sensors

Swamy, Chinna Ayya P and Mukherjee, Sanjoy and Thilagar, Pakkirisamy (2014) Dual Binding Site Assisted Chromogenic and Fluorogenic Recognition and Discrimination of Fluoride and Cyanide by a Peripherally Borylated Metalloporphyrin: Overcoming Anion Interference in Organoboron Based Sensors. In: ANALYTICAL CHEMISTRY, 86 (7). pp. 3616-3624.

PDF ana_che_86-7_3616_2014.pdf - Published Version Restricted to Registered users only Download (4MB) | Request a copy

Abstract

Peripherally triarylborane decorated porphyrin (2) and its Zn(II) complex (3) have been synthesized. Compound 3 contains of two different Lewis acidic binding sites (Zn(II) and boron center). Unlike all previously known triarylborane based sensors, the optical responses of 3 toward fluoride and cyanide are distinctively different, thus enabling the discrimination of these two interfering anions. Metalloporphyrin 3 shows a multiple channel fluorogenic response toward fluoride and cyanide and also a selective visual colorimetric response toward cyanide. By comparison with model systems and from detailed photophysical studies on 2 and 3, we conclude that the preferential binding of fluoride occurs at the peripheral borane moieties resulting in the cessation of the EET (electronic energy transfer) process from borane to porphyrin core and with negligible negetive cooperative effects. On the other hand, cyanide binding occurs at the Zn(II) core leading to drastic changes in its absorption behavior which can be followed by the naked eye. Such changes are not observed when the boryl substituent is absent (e.g., Zn-TPP and TPP). Compounds 2 and 3 were also found to be capable of extracting fluoride from aqueous medium.

Item Type:	Journal Article
Publication:	ANALYTICAL CHEMISTRY
Publisher:	AMER CHEMICAL SOC
Additional Information:	Copyright for this article belongs to the AMER CHEMICAL SOC, USA
Department/Centre:	Division of Chemical Sciences > Inorganic & Physical Chemistry
Date Deposited:	19 May 2014 06:06
Last Modified:	19 May 2014 06:06
URI:	http://eprints.iisc.ac.in/id/eprint/49097

Actions (login required)

View Item