Switching Properties of a Spiropyran-Cucurbit [7] uril Supramolecular Assembly: Usefulness of the Anchor Approach
Journal article, 2012
A nitrospiropyran, which was modified with a cadaverine-derived anchor, was investigated with respect to its thermally induced isomerizations, hydrolytic stability of the merocyanine form, and photochromic ring closure. The hostguest complexation of the anchor by the cucurbit[7]uril macrocycle, evidenced by absorption titration, NMR spectroscopy, and electrospray ionization mass spectrometry, produced significant improvements of the switching properties of the photochrome: 1) appearance of the merocyanine form about 70 times faster, 2) practically unlimited hydrolytic stability of the merocyanine (two and a half days without any measureable decay), and 3) fast, clean, and fatigue-resistant photoinduced ring closure back to the spiro form. The importance of an adequate molecular design of the anchor was demonstrated by including control experiments with spiropyrans with a shorter linker or without such structural asset.
photochromism
host-guest chemistry
aqueous-solution
hydrolysis
acidochromism
energy-transfer
drug-delivery
fluorescent dye
photoswitchable nanoparticles
shifts
cucurbiturils
lock-in detection
cucurbiturils
molecular switches
pk(a)
complexes
Author
Jesper Nilsson
Chalmers, Chemical and Biological Engineering, Physical Chemistry
C. P. Carvalho
University of Huelva
Shiming Li
Chalmers, Chemical and Biological Engineering, Physical Chemistry
J. P. Da Silva
University of Algarve
Joakim Andreasson
Chalmers, Chemical and Biological Engineering, Physical Chemistry
U. Pischel
University of Huelva
ChemPhysChem
1439-4235 (ISSN) 1439-7641 (eISSN)
Vol. 13 16 3691-3699Photonic switching of molecular properties using photochromes
Swedish Research Council (VR) (2010-280), 2011-01-01 -- 2016-12-31.
Photochromic Systems for Solid State Molecular Electronic Devices and Light-Activated Cancer Drugs (PHOTOCHROMES)
European Commission (EC) (EC/FP7/203952), 2008-09-01 -- 2013-08-31.
Subject Categories
Chemical Sciences
DOI
10.1002/cphc.201200468