Rational design, synthesis, and application of a new receptor for the molecular recognition of tricarboxylate salts in aqueous media.
A rational design of a tripodal receptor for the molecular recognition of tricarboxylate salts in aqueous media, based on squaramide, has been performed using high-level DFT calculations (RI-BP86/SVP level of theory) in solution using the COSMO treatment, including some preliminary ab initio calculations at the higher RI-MP2/TZVP level of theory, comparing the ability of squaramide to bind carboxylate salts with two widely used guanidinium salts. The tripodal receptor has been synthesized using a new methodology that has been recently reported by some of us, and its capability of recognizing several mono-, di-, and tricarboxylate salts has been studied experimentally by means of microcalorimetry experiments in a very high competitive media, H(2)O:EtOH 1:3. These experiments give enthalpic and entropic data, which are unfortunately scarce in the literature of molecular recognition of anions. Finally, a fluorimetric ensemble of the receptor with fluorescein has been found to be useful for the fluorimetric determination of zinc citrate in a commercial toothpaste using competition assays.
Frontera
Antonio
A
Department of Chemistry, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca, Spain. toni.frontera@uib.es
Morey
Jeroni
J
Oliver
Antonia
A
Piña
M Neus
MN
Quiñonero
David
D
Costa
Antoni
A
Ballester
Pablo
P
Deyà
Pere M
PM
Anslyn
Eric V
EV
D001665:Binding Sites; D003503:Cyclobutanes / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D012996:Solutions; D014233:Tricarboxylic Acids / Q000302:isolation & purification*
D003503:Cyclobutanes; D000644:Quaternary Ammonium Compounds; D012996:Solutions; D014233:Tricarboxylic Acids