posted on 2020-03-31, 12:35authored byS. Maryamdokht Taimoory, Kwaku Twum, Mohadeseh Dashti, Fangfang Pan, Manu Lahtinen, Kari Rissanen, Rakesh Puttreddy, John F. Trant, Ngong Kodiah Beyeh
Cethyl-2-methylresorcinarene (A), pyridine
(B), and a set of 10 carboxylic acids (Cn) associate to form A·B·Cn ternary assemblies with 1:1:1 stoichiometry, representing
a useful class of ternary systems where the guest mediates complex
formation between the host and a third component. Although individually
weak in solution, the combined strength of the multiple noncovalent
interactions organizes the complexes even in a highly hydrogen-bond
competing methanol solution, as explored by both experimental and
computational methods. The interactions between A·B and Cn are dependent on the pKa values of carboxylic acids. The weak interactions
between A and C further reinforce the interactions
between A and B, demonstrating positive
cooperativity. Our results reveal that the two-component system such
as that formed by A and B can form the basis
for the development of specific sensors for the molecular recognition
of carboxylic acids.