Water vs. cucurbituril rim: a fierce competition for guest solvation.

ABSTRACT: The impact of remote substituents on the affinity of cucurbit[n]urils (CB[n]) towards a homologous series of guests, which differ from one another only by a single substituent, and adopt the same geometry within the cavity of the macrocycle, is presented for the first time, and is used to decipher the competition between water and the carbonylated portal of CB[7] for the stabilization of positively charged guests. Binding affinities of CB[7] towards substituted N-benzyl-trimethylsilylmethylammonium cations relative to the unsubstituted member (X = H) range from 0.9 (X = CH₃) to 3.1 (X = SO₂CF₃), and correlate very precisely with a linear combination of Swain-Lupton field/inductive (F; 67%) and resonance (R; 33%) parameters

SUBMITTER: Ling X 

PROVIDER: S-EPMC6007185 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature