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Shape-Adaptability and Redox-Switching Properties of a Di-Gold Metallotweezer.

ABSTRACT: The use of a carbazolyl-connected di-gold(I) metallotweezer for the encapsulation of several electron-poor organic substrates, and a planar Au(III) complex containing a CNC pincer ligand, is described. The binding affinity of the receptor depends on the electron-deficient character of the planar guest, with larger association constants found for the more electron-poor guests. The X-ray diffraction molecular structures of two host:guest adducts show that the host approaches its arms in order to facilitate the optimum interaction with the surface of the planar guests, in a clear example of an guest-induced fit conformational arrangement. The electrochemical studies of the encapsulation of N,N'-dimethyl-naphthalenetetracarboxy diimide (NTCDI) show that the redox active guest is released from the receptor upon one electron reduction, thus constituting an example of redox-switchable binding.

SUBMITTER: Ibanez S

PROVIDER: S-EPMC8362111 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Shape-Adaptability and Redox-Switching Properties of a Di-Gold Metallotweezer.

Ibáñez Susana S Peris Eduardo E

Chemistry (Weinheim an der Bergstrasse, Germany) 20210521 37

The use of a carbazolyl-connected di-gold(I) metallotweezer for the encapsulation of several electron-poor organic substrates, and a planar Au(III) complex containing a CNC pincer ligand, is described. The binding affinity of the receptor depends on the electron-deficient character of the planar guest, with larger association constants found for the more electron-poor guests. The X-ray diffraction molecular structures of two host:guest adducts show that the host approaches its arms in order to f ...[more]

PMID: 33844341

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