Abstract
Bis(benzimidazolium)butane (BBIM-butane) system acts as a new guest molecule for dibenzo-24-crown-8 (DB24C8). This is the only [BBIM]DB24C8 pseudorotaxanes where two conformers coexist (detected by 1 H NMR and structure established by DFT studies); major conformer and minor conformer. Low temperature 1 H NMR (240, 253 K) was done for a representative [BBIM-butane] DB24C8 pseudorotaxane that could not be detected at room-temperature. DFT calculations for this [BBIM-butane] DB24C8 pseudorotaxane were done both with B3LYP and MPW1PW91 functionals. The MPW1PW91 optimized structures identified possible stable major and minor conformer with the strongest H-bonding. We have compared the characteristics of [BBIM]DB24C8 [2]pseudorotaxanes comprising the [BBIM-methane]DB24C8, [BBIM-ethane] DB24C8, [BBIM-propane]DB24C8 and [BBIM-butane] DB24C8 systems. The feasibility of formation of these pseudorotaxanes decreases considerably from [BBIMmethane] DB24C8 to the [BBIM-butane]DB24C8 system. The presence of these threaded complexes was initially screened based on 1 H NMR and substantiated further by 2D NMR spectroscopy (NOESY and COSY), X-ray crystallography, HR-ESI-MS and DFT calculations.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 321-340 |
| Number of pages | 20 |
| Journal | Journal of Inclusion Phenomena and Macrocyclic Chemistry |
| Volume | 81 |
| Issue number | 3-4 |
| DOIs | |
| State | Published - Apr 1 2015 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Food Science
- Chemistry(all)
- Condensed Matter Physics
Cite this
}
Anomalous behaviour of the bis(benzimidazolium)butane [2]pseudorotaxanes of dibenzo-24-crown-8 : A comparative study of methane, ethane, propane and butane bis(benzimidazolium)alkane]dibenzo-24-crown-8 systems with variable spacers. / Ghosh, Sabari; Schmiedekamp, Ann Marie; Padmanaban, E.; Butcher, Ray J.; Chaudhuri, Tandrima; Rao, Nina; Mukhopadhyay, Chhanda.
In: Journal of Inclusion Phenomena and Macrocyclic Chemistry, Vol. 81, No. 3-4, 01.04.2015, p. 321-340.Research output: Contribution to journal › Article
TY - JOUR
T1 - Anomalous behaviour of the bis(benzimidazolium)butane [2]pseudorotaxanes of dibenzo-24-crown-8
T2 - A comparative study of methane, ethane, propane and butane bis(benzimidazolium)alkane]dibenzo-24-crown-8 systems with variable spacers
AU - Ghosh, Sabari
AU - Schmiedekamp, Ann Marie
AU - Padmanaban, E.
AU - Butcher, Ray J.
AU - Chaudhuri, Tandrima
AU - Rao, Nina
AU - Mukhopadhyay, Chhanda
PY - 2015/4/1
Y1 - 2015/4/1
N2 - Bis(benzimidazolium)butane (BBIM-butane) system acts as a new guest molecule for dibenzo-24-crown-8 (DB24C8). This is the only [BBIM]DB24C8 pseudorotaxanes where two conformers coexist (detected by 1 H NMR and structure established by DFT studies); major conformer and minor conformer. Low temperature 1 H NMR (240, 253 K) was done for a representative [BBIM-butane] DB24C8 pseudorotaxane that could not be detected at room-temperature. DFT calculations for this [BBIM-butane] DB24C8 pseudorotaxane were done both with B3LYP and MPW1PW91 functionals. The MPW1PW91 optimized structures identified possible stable major and minor conformer with the strongest H-bonding. We have compared the characteristics of [BBIM]DB24C8 [2]pseudorotaxanes comprising the [BBIM-methane]DB24C8, [BBIM-ethane] DB24C8, [BBIM-propane]DB24C8 and [BBIM-butane] DB24C8 systems. The feasibility of formation of these pseudorotaxanes decreases considerably from [BBIMmethane] DB24C8 to the [BBIM-butane]DB24C8 system. The presence of these threaded complexes was initially screened based on 1 H NMR and substantiated further by 2D NMR spectroscopy (NOESY and COSY), X-ray crystallography, HR-ESI-MS and DFT calculations.
AB - Bis(benzimidazolium)butane (BBIM-butane) system acts as a new guest molecule for dibenzo-24-crown-8 (DB24C8). This is the only [BBIM]DB24C8 pseudorotaxanes where two conformers coexist (detected by 1 H NMR and structure established by DFT studies); major conformer and minor conformer. Low temperature 1 H NMR (240, 253 K) was done for a representative [BBIM-butane] DB24C8 pseudorotaxane that could not be detected at room-temperature. DFT calculations for this [BBIM-butane] DB24C8 pseudorotaxane were done both with B3LYP and MPW1PW91 functionals. The MPW1PW91 optimized structures identified possible stable major and minor conformer with the strongest H-bonding. We have compared the characteristics of [BBIM]DB24C8 [2]pseudorotaxanes comprising the [BBIM-methane]DB24C8, [BBIM-ethane] DB24C8, [BBIM-propane]DB24C8 and [BBIM-butane] DB24C8 systems. The feasibility of formation of these pseudorotaxanes decreases considerably from [BBIMmethane] DB24C8 to the [BBIM-butane]DB24C8 system. The presence of these threaded complexes was initially screened based on 1 H NMR and substantiated further by 2D NMR spectroscopy (NOESY and COSY), X-ray crystallography, HR-ESI-MS and DFT calculations.
UR - http://www.scopus.com/inward/record.url?scp=84929574987&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84929574987&partnerID=8YFLogxK
U2 - 10.1007/s10847-014-0459-6
DO - 10.1007/s10847-014-0459-6
M3 - Article
AN - SCOPUS:84929574987
VL - 81
SP - 321
EP - 340
JO - Journal of Inclusion Phenomena and Macrocyclic Chemistry
JF - Journal of Inclusion Phenomena and Macrocyclic Chemistry
SN - 1388-3127
IS - 3-4
ER -