Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane

Najat S. Khan, Jose Manuel Perez-Aguilar, Tara Kaufmann, P. Aru Hill, Olena Taratula, One-Sun Lee, Patrick J. Carroll, Jeffery G. Saven, Ivan J. Dmochowski

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

A gyroscope-inspired tribenzylamine hemicryptophane provides a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The hemicryptophane was synthesized in three steps in good overall yield using mild conditions. Three rotator-forming linkers were cyclized to form a rigid cyclotriveratrylene (CTV) stator framework, which was then closed with an amine. The gyroscope-like molecule was characterized by 1H NMR and 13C NMR spectroscopy, and the structure was solved by X-ray crystallography. The rigidity of the two-component CTV-trismethylamine stator was investigated by 1H variable-temperature (VT) NMR experiments and molecular dynamics simulations. These techniques identified gyration of the three p-phenylene rotators on the millisecond time scale at -93 °C, with more dynamic but still hindered motion at room temperature (27 °C). The activation energy for the p-phenylene rotation was determined to be ?10 kcal mol-1. Due to the propeller arrangement of the p-phenylenes, their rotation is hindered but not strongly correlated. The compact size, simple synthetic route, and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.(Figure Presented)

Original languageEnglish
Pages (from-to)1418-1424
Number of pages7
JournalJournal of Organic Chemistry
Volume76
Issue number5
DOIs
Publication statusPublished - 4 Mar 2011
Externally publishedYes

Fingerprint

Gyroscopes
Stators
Temperature
X Ray Crystallography
Molecular Dynamics Simulation
Nuclear magnetic resonance
Amines
Molecules
Magnetic Resonance Spectroscopy
X ray crystallography
Propellers
Rigidity
Nuclear magnetic resonance spectroscopy
Molecular dynamics
Activation energy
Computer simulation
tribenzylamine
cyclotriveratrylene
Experiments
Direction compound

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Khan, N. S., Perez-Aguilar, J. M., Kaufmann, T., Hill, P. A., Taratula, O., Lee, O-S., ... Dmochowski, I. J. (2011). Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane. Journal of Organic Chemistry, 76(5), 1418-1424. https://doi.org/10.1021/jo102480s

Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane. / Khan, Najat S.; Perez-Aguilar, Jose Manuel; Kaufmann, Tara; Hill, P. Aru; Taratula, Olena; Lee, One-Sun; Carroll, Patrick J.; Saven, Jeffery G.; Dmochowski, Ivan J.

In: Journal of Organic Chemistry, Vol. 76, No. 5, 04.03.2011, p. 1418-1424.

Research output: Contribution to journalArticle

Khan, NS, Perez-Aguilar, JM, Kaufmann, T, Hill, PA, Taratula, O, Lee, O-S, Carroll, PJ, Saven, JG & Dmochowski, IJ 2011, 'Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane', Journal of Organic Chemistry, vol. 76, no. 5, pp. 1418-1424. https://doi.org/10.1021/jo102480s
Khan, Najat S. ; Perez-Aguilar, Jose Manuel ; Kaufmann, Tara ; Hill, P. Aru ; Taratula, Olena ; Lee, One-Sun ; Carroll, Patrick J. ; Saven, Jeffery G. ; Dmochowski, Ivan J. / Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane. In: Journal of Organic Chemistry. 2011 ; Vol. 76, No. 5. pp. 1418-1424.
@article{b27a6c90e842426a85c4ca35a13c2acd,
title = "Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane",
abstract = "A gyroscope-inspired tribenzylamine hemicryptophane provides a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The hemicryptophane was synthesized in three steps in good overall yield using mild conditions. Three rotator-forming linkers were cyclized to form a rigid cyclotriveratrylene (CTV) stator framework, which was then closed with an amine. The gyroscope-like molecule was characterized by 1H NMR and 13C NMR spectroscopy, and the structure was solved by X-ray crystallography. The rigidity of the two-component CTV-trismethylamine stator was investigated by 1H variable-temperature (VT) NMR experiments and molecular dynamics simulations. These techniques identified gyration of the three p-phenylene rotators on the millisecond time scale at -93 °C, with more dynamic but still hindered motion at room temperature (27 °C). The activation energy for the p-phenylene rotation was determined to be ?10 kcal mol-1. Due to the propeller arrangement of the p-phenylenes, their rotation is hindered but not strongly correlated. The compact size, simple synthetic route, and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.(Figure Presented)",
author = "Khan, {Najat S.} and Perez-Aguilar, {Jose Manuel} and Tara Kaufmann and Hill, {P. Aru} and Olena Taratula and One-Sun Lee and Carroll, {Patrick J.} and Saven, {Jeffery G.} and Dmochowski, {Ivan J.}",
year = "2011",
month = "3",
day = "4",
doi = "10.1021/jo102480s",
language = "English",
volume = "76",
pages = "1418--1424",
journal = "Journal of Organic Chemistry",
issn = "0022-3263",
publisher = "American Chemical Society",
number = "5",

}

TY - JOUR

T1 - Multiple hindered rotators in a gyroscope-inspired tribenzylamine hemicryptophane

AU - Khan, Najat S.

AU - Perez-Aguilar, Jose Manuel

AU - Kaufmann, Tara

AU - Hill, P. Aru

AU - Taratula, Olena

AU - Lee, One-Sun

AU - Carroll, Patrick J.

AU - Saven, Jeffery G.

AU - Dmochowski, Ivan J.

PY - 2011/3/4

Y1 - 2011/3/4

N2 - A gyroscope-inspired tribenzylamine hemicryptophane provides a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The hemicryptophane was synthesized in three steps in good overall yield using mild conditions. Three rotator-forming linkers were cyclized to form a rigid cyclotriveratrylene (CTV) stator framework, which was then closed with an amine. The gyroscope-like molecule was characterized by 1H NMR and 13C NMR spectroscopy, and the structure was solved by X-ray crystallography. The rigidity of the two-component CTV-trismethylamine stator was investigated by 1H variable-temperature (VT) NMR experiments and molecular dynamics simulations. These techniques identified gyration of the three p-phenylene rotators on the millisecond time scale at -93 °C, with more dynamic but still hindered motion at room temperature (27 °C). The activation energy for the p-phenylene rotation was determined to be ?10 kcal mol-1. Due to the propeller arrangement of the p-phenylenes, their rotation is hindered but not strongly correlated. The compact size, simple synthetic route, and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.(Figure Presented)

AB - A gyroscope-inspired tribenzylamine hemicryptophane provides a vehicle for exploring the structure and properties of multiple p-phenylene rotators within one molecule. The hemicryptophane was synthesized in three steps in good overall yield using mild conditions. Three rotator-forming linkers were cyclized to form a rigid cyclotriveratrylene (CTV) stator framework, which was then closed with an amine. The gyroscope-like molecule was characterized by 1H NMR and 13C NMR spectroscopy, and the structure was solved by X-ray crystallography. The rigidity of the two-component CTV-trismethylamine stator was investigated by 1H variable-temperature (VT) NMR experiments and molecular dynamics simulations. These techniques identified gyration of the three p-phenylene rotators on the millisecond time scale at -93 °C, with more dynamic but still hindered motion at room temperature (27 °C). The activation energy for the p-phenylene rotation was determined to be ?10 kcal mol-1. Due to the propeller arrangement of the p-phenylenes, their rotation is hindered but not strongly correlated. The compact size, simple synthetic route, and molecular motions of this gyroscope-inspired tribenzylamine hemicryptophane make it an attractive starting point for controlling the direction and coupling of rotators within molecular systems.(Figure Presented)

UR - http://www.scopus.com/inward/record.url?scp=79952177176&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79952177176&partnerID=8YFLogxK

U2 - 10.1021/jo102480s

DO - 10.1021/jo102480s

M3 - Article

C2 - 21271707

AN - SCOPUS:79952177176

VL - 76

SP - 1418

EP - 1424

JO - Journal of Organic Chemistry

JF - Journal of Organic Chemistry

SN - 0022-3263

IS - 5

ER -