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Current Chemical Biology

Author(s): Nallamuthu Prabhu, Jyoti, Renu Kumari, Jai Deo Singh* and Raymond J. Butcher

DOI: 10.2174/2212796816666220509145236

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Acyclic Polyorganochalcogenoethers and their Functional Activities: Synthesis of Sterically Encumbered Hexakis(alkylchalcogenomethyl)benzenes [(RECH2)6C6] [E=S or Se] and their Potential as Selective Ionophores for Hg2+ Ions

Page: [35 - 43] Pages: 9

  • * (Excluding Mailing and Handling)

Abstract

Introduction: An efficient synthesis of hexakis(alkylthio/selenomethyl)benzenes [(RSCH2)6C6 and (RSeCH2)6C6] (1-14) (where, R= nPr, iPr, nBu, iBu, sBu, tBu, nPent, iPent, and 2- Methyl-1-butyl) by the reaction of hexakis(bromomethyl)benzene with alkylthio or alkylseleno (RS- /RSe-) anions is demonstrated.

Methods: They have been characterized by physicochemical and spectroscopic methods, including single-crystal X-ray crystallography. The balances between multiple [C(sp3)-H…S] or [C(sp3)-H…Se] intramolecular interactions in these species appear to decide their stability. Preliminary spectroscopic (UV-vis. and fluorescence) data on the behavior of alkylchalcogeno substituted hexa-benzenes in solution revealed their potential as ion-sensing species and function as highly selective ionophores for Ag+ and Hg2+ ions recognition.

Results: In situ, (Hg-S) and (Hg-Se) bond formation on interaction with the chosen hexa-species (2 and 10) and Hg2+ cation revealed a unique ‘turn-off’ or ‘turn-on’ emissive behavior, and these functions act as reporting fluorescent tools for Hg2+ quantification without use of any external fluorophore.

Conclusion: The present study describes an efficient and simple route for the synthesis of sterically encumbered poly-alkylthio/seleno benzenes in high purity and good yields.

Keywords: Alkylthiolate, alkylselenolate, hexa-substitution, Hg2+ ion recognition, (Hg-S) (Hg-Se) bond, antimicrobial activity.

Graphical Abstract

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