TY - JOUR
T1 - Very Strong Binding for a Neutral Calix[4]pyrrole Receptor Displaying Positive Allosteric Binding
AU - Duedal, Troels
AU - Nielsen, Kent
AU - Olsen, Gunnar
AU - Burgdorf Guldager Rasmussen, Charlotte
AU - Kongsted, Jacob
AU - Levillain, Eric
AU - Breton, Tony
AU - Miyazaki, Eigo
AU - Takimiya, Kazuo
AU - Bähring, Steffen
AU - Jeppesen, Jan Oskar
PY - 2017
Y1 - 2017
N2 - The dual-analyte responsive behavior of tetraTTF-calix[4]pyrrole receptor 1 has shown to complex electron-deficient planar guests in a 2:1 fashion in the so-called 1,3-alternate conformation. However, stronger 1:1 complexes have been demonstrated with tetraalkylammonium halide salts that defer receptor 1 to its so-called cone conformation. Herein, we report the complexation of an electron-deficient planar guest, namely 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA, 2), that champions the complexation with 1 resulting in a very high association constant Ka = 3 × 1010 M−2. The tetrathiafulvalene (TTF) subunits in the tetraTTF-calix[4]pyrrole receptor 1 present a nearly perfect shape and electronic complementarity to the NTCDA guest, which was confirmed by X-ray crystal structure analysis, DFT calculations, and electron density surface mapping. The complexation results in formation of a charge transfer complex (22⊆1), that is visualized as a color change from yellow to brown.
AB - The dual-analyte responsive behavior of tetraTTF-calix[4]pyrrole receptor 1 has shown to complex electron-deficient planar guests in a 2:1 fashion in the so-called 1,3-alternate conformation. However, stronger 1:1 complexes have been demonstrated with tetraalkylammonium halide salts that defer receptor 1 to its so-called cone conformation. Herein, we report the complexation of an electron-deficient planar guest, namely 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA, 2), that champions the complexation with 1 resulting in a very high association constant Ka = 3 × 1010 M−2. The tetrathiafulvalene (TTF) subunits in the tetraTTF-calix[4]pyrrole receptor 1 present a nearly perfect shape and electronic complementarity to the NTCDA guest, which was confirmed by X-ray crystal structure analysis, DFT calculations, and electron density surface mapping. The complexation results in formation of a charge transfer complex (22⊆1), that is visualized as a color change from yellow to brown.
U2 - 10.1021/acs.joc.6b02944
DO - 10.1021/acs.joc.6b02944
M3 - Journal article
C2 - 28121143
VL - 82
SP - 2123
EP - 2128
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
SN - 0022-3263
IS - 4
ER -