Author, as appears in the article.: Sun, Qingqing; Escobar, Luis; Ballester, Pablo;

Department: Química Analítica i Química Orgànica

URV's Author/s: Sun, Qingqing

Keywords: Amides Aromatic compounds Binding geometries Binding studies Complexation Host-guest systems Hydrolysis Hydrolysis reaction Inclusion complex Isonitriles Kinetic properties Methylene groups Molecular containers Molecules Mono-functionalization Protecting group Reacting groups Reaction rates

Abstract: We report binding studies of an octa-pyridinium super aryl-extended calix[4]pyrrole receptor with neutral difunctional aliphatic guests in water. The guests have terminal isonitrile and formamide groups, and the complexes display an inclusion binding geometry and 1:1 stoichiometry. Using H-1 NMR titrations and ITC experiments, we characterized the dissimilar thermodynamic and kinetic properties of the complexes. The bis-isonitriles possess independent reacting groups, however, in the presence of 1 equiv of the receptor the hydrolysis reaction produces mixtures of non-statistical composition and a significant decrease in reaction rates. The selectivity for the mono-formamide product is specially enhanced in the case of the bis-isonitrile having a spacer with five methylene groups. The analysis of the kinetic data suggests that the observed modifications in reaction rates and selectivity are related to the formation of highly stable inclusion complexes in which the isonitrile is hidden from bulk water molecules. The concentration of the reacting substrates in the bulk solution is substantially reduced by binding to the receptor. In turn, the hydrolysis rates of the isonitrile groups for the bound substrates are slower than in the bulk solution. The receptor acts as both a sequestering and supramolecular protecting group.

Thematic Areas: Astronomia / física Catalysis Chemistry Chemistry (miscellaneous) Chemistry, multidisciplinary Ciências biológicas i Ciências biológicas ii Ciências biológicas iii Engenharias ii Farmacia General chemistry General medicine Interdisciplinar Materiais Medicina i Medicina ii Química

licence for use: https://creativecommons.org/licenses/by/3.0/es/

Author's mail: qingqing.sun@estudiants.urv.cat

Author identifier: 0000-0002-5088-1243

Record's date: 2022-01-16

Papper version: info:eu-repo/semantics/acceptedVersion

Link to the original source: https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202101499

Papper original source: Angewandte Chemie (International Ed. Print). 60 (18): 10359-10365

APA: Sun, Qingqing; Escobar, Luis; Ballester, Pablo; (2021). Hydrolysis of Aliphatic Bis-isonitriles in the Presence of a Polar Super Aryl-Extended Calix[4]pyrrole Container. Angewandte Chemie (International Ed. Print), 60(18), 10359-10365. DOI: 10.1002/anie.202101499

Licence document URL: http://repositori.urv.cat/ca/proteccio-de-dades/

Article's DOI: 10.1002/anie.202101499

Entity: Universitat Rovira i Virgili

Journal publication year: 2021

Publication Type: Journal Publications