Insights Into the Gelation of Biphenyl Coupled Pyridyl Bisamides

doi:10.21127/yaoyigc20200004

Abstract

Abstract: Biphenyl coupled isomeric pyridyl bisamides 1—4 have been synthesized and their gelation propensities have been thoroughly investigated. In spite of having a pyridine center, capable of forming water linking network and hydrogen bonding amide functionality, all the compounds behave as non-gelator in organic and semi aqueous solvents. However, in presence of Ag+ ions, only compound 1 forms gel and validates its visual sensing over other metal ions. The nongelation behaviour of other derivatives 2, 3 and also meta derivative 4 highlights the effect of positional role of the pyridine ring nitrogen with respect to the biphenyl ring as well as endorse the isomeric substitution in biphenyl ring, respectively. Spectroscopic studies confirm that the metal coordination as well as the hydrogen bonding involving the amide NHs of 1 plays a pivotal role in establishing the gel network in solution. Not only through gelation, compound 1 also selectively recognizes Ag⁺ ions fluorimetrically in a turn-on mode in solution state and correlates the gel phase observations.

Key words: supramolecular gels, biphenyl-linked bispyridine amide, stimuli responsiveness, Ag⁺ sensing, fluorometric detection

Santanu Panja, and Kumaresh Ghosh. Insights Into the Gelation of Biphenyl Coupled Pyridyl Bisamides[J]. General Chemistry, DOI: 10.21127/yaoyigc20200004.

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