Abstract
Solid-state superstructures, resulting from assemblies programmed by homochirality, are attracting considerable attention. In addition, artificial double-helical architectures are being investigated, especially in relation to the ways in which homochiral small molecules can be induced to yield helical forms as a result of chiral induction. Herein, we report the highly specific self-assembly upon crystallization of a double-helical superstructure from an enantiopure macrocyclic dimer which adopts two diastereoisomeric conformations in a molar ratio of 1.5:1 in dimethyl sulfoxide. These two conformational diastereoisomers self-organize - and self-sort - in the crystalline phase in equimolar proportions to form two single-handed helices which are complementary to each other, giving rise to the assembly of a double helix that is stabilized by intermolecular [C-H···O] and stacking interactions. The observed self-sorting phenomenon occurs on going from a mixed-solvent system containing two equilibrating conformational diastereoisomers, presumably present in unequal molar proportions, into the solid state. The diastereoisomeric conformations are captured upon crystallization in a 1:1 molar ratio in the double-helical superstructure, whose handedness is dictated by the choice of the enantiomeric macrocyclic dimer. The interconversion of the two conformational diastereoisomers derived from each configurationally enantiomeric macrocycle was investigated in CD3SOCD3 solution by variable-temperature 1H NMR spectroscopy (VT NMR) and circular dichroism (VT CD). The merging of the resonances for the protons corresponding to the two diastereoisomers at a range of coalescence temperatures in the VT NMR spectra and occurrence of the isosbestic points in the VT CD spectra indicate that the two diastereoisomers are interconverting slowly in solution on the 1H NMR time scale but rapidly on the laboratory time scale. To the best of our knowledge, the self-assembly of such solid-state superstructures from two conformational diastereoisomers of a homochiral macrocycle is a rare, if not unique, occurrence.
| Original language | English |
|---|---|
| Pages (from-to) | 14469-14480 |
| Number of pages | 12 |
| Journal | Journal of the American Chemical Society |
| Volume | 138 |
| Issue number | 43 |
| DOIs | |
| Publication status | Published - Nov 2 2016 |
Fingerprint
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)
- Biochemistry
- Colloid and Surface Chemistry
Cite this
Supramolecular Double-Helix Formation by Diastereoisomeric Conformations of Configurationally Enantiomeric Macrocycles. / Samanta, Avik; Liu, Zhichang; Nalluri, Siva Krishna Mohan; Zhang, Yu; Schatz, George C; Stoddart, J. Fraser.
In: Journal of the American Chemical Society, Vol. 138, No. 43, 02.11.2016, p. 14469-14480.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Supramolecular Double-Helix Formation by Diastereoisomeric Conformations of Configurationally Enantiomeric Macrocycles
AU - Samanta, Avik
AU - Liu, Zhichang
AU - Nalluri, Siva Krishna Mohan
AU - Zhang, Yu
AU - Schatz, George C
AU - Stoddart, J. Fraser
PY - 2016/11/2
Y1 - 2016/11/2
N2 - Solid-state superstructures, resulting from assemblies programmed by homochirality, are attracting considerable attention. In addition, artificial double-helical architectures are being investigated, especially in relation to the ways in which homochiral small molecules can be induced to yield helical forms as a result of chiral induction. Herein, we report the highly specific self-assembly upon crystallization of a double-helical superstructure from an enantiopure macrocyclic dimer which adopts two diastereoisomeric conformations in a molar ratio of 1.5:1 in dimethyl sulfoxide. These two conformational diastereoisomers self-organize - and self-sort - in the crystalline phase in equimolar proportions to form two single-handed helices which are complementary to each other, giving rise to the assembly of a double helix that is stabilized by intermolecular [C-H···O] and stacking interactions. The observed self-sorting phenomenon occurs on going from a mixed-solvent system containing two equilibrating conformational diastereoisomers, presumably present in unequal molar proportions, into the solid state. The diastereoisomeric conformations are captured upon crystallization in a 1:1 molar ratio in the double-helical superstructure, whose handedness is dictated by the choice of the enantiomeric macrocyclic dimer. The interconversion of the two conformational diastereoisomers derived from each configurationally enantiomeric macrocycle was investigated in CD3SOCD3 solution by variable-temperature 1H NMR spectroscopy (VT NMR) and circular dichroism (VT CD). The merging of the resonances for the protons corresponding to the two diastereoisomers at a range of coalescence temperatures in the VT NMR spectra and occurrence of the isosbestic points in the VT CD spectra indicate that the two diastereoisomers are interconverting slowly in solution on the 1H NMR time scale but rapidly on the laboratory time scale. To the best of our knowledge, the self-assembly of such solid-state superstructures from two conformational diastereoisomers of a homochiral macrocycle is a rare, if not unique, occurrence.
AB - Solid-state superstructures, resulting from assemblies programmed by homochirality, are attracting considerable attention. In addition, artificial double-helical architectures are being investigated, especially in relation to the ways in which homochiral small molecules can be induced to yield helical forms as a result of chiral induction. Herein, we report the highly specific self-assembly upon crystallization of a double-helical superstructure from an enantiopure macrocyclic dimer which adopts two diastereoisomeric conformations in a molar ratio of 1.5:1 in dimethyl sulfoxide. These two conformational diastereoisomers self-organize - and self-sort - in the crystalline phase in equimolar proportions to form two single-handed helices which are complementary to each other, giving rise to the assembly of a double helix that is stabilized by intermolecular [C-H···O] and stacking interactions. The observed self-sorting phenomenon occurs on going from a mixed-solvent system containing two equilibrating conformational diastereoisomers, presumably present in unequal molar proportions, into the solid state. The diastereoisomeric conformations are captured upon crystallization in a 1:1 molar ratio in the double-helical superstructure, whose handedness is dictated by the choice of the enantiomeric macrocyclic dimer. The interconversion of the two conformational diastereoisomers derived from each configurationally enantiomeric macrocycle was investigated in CD3SOCD3 solution by variable-temperature 1H NMR spectroscopy (VT NMR) and circular dichroism (VT CD). The merging of the resonances for the protons corresponding to the two diastereoisomers at a range of coalescence temperatures in the VT NMR spectra and occurrence of the isosbestic points in the VT CD spectra indicate that the two diastereoisomers are interconverting slowly in solution on the 1H NMR time scale but rapidly on the laboratory time scale. To the best of our knowledge, the self-assembly of such solid-state superstructures from two conformational diastereoisomers of a homochiral macrocycle is a rare, if not unique, occurrence.
UR - http://www.scopus.com/inward/record.url?scp=84994240172&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84994240172&partnerID=8YFLogxK
U2 - 10.1021/jacs.6b09258
DO - 10.1021/jacs.6b09258
M3 - Article
VL - 138
SP - 14469
EP - 14480
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 43
ER -