Photoresponsive Crown Ethers. 1. Cis-Trans Isomerism of Azobenzene as a Tool to Enforce Conformational Changes of Crown Ethers and Polymers

Seiji Shinkai, Takahiro Nakaji, Yoshihiro Nishida, Toshiyuki Ogawa, Osamu Manabe

Research output: Contribution to journalArticle

226 Citations (Scopus)

Abstract

An azobenzene-bridged crown ether (2) and a polymer containing both crown ether unit and azobenzene unit (4) were synthesized. 2 bridged with trans-azobenzene (trans-1) bound an ammonium cation (5) and methyl orange salts of Li+ and Na+ preferably, whereas 2 bridged with photo- (UV) isomerized cA-azobenzene (cis-2) bound methyl orange salts of K+ and Rb+ preferably. The result was rationalized in terms of photoinduced expansion of the crown ether size. The binding ability of polymer 4 was also subject to photoirradiation. In particular, the crown ether units adjoining the cA-azobenzene unit lost the affinity toward Na+ ion. The conformational changes of the crown ether and the polymer were conveniently monitored by following the spontaneous regeneration of trans-azobenzene in the dark. It was established on the basis of the rate measurements that (i) the conformational fluctuation of the crown ether is suppressed by K+ and ammonium cations, (ii) the extension of the polymer chain in solution accompanies a large entropy increase, and (iii) ∆H* and ∆S* for the rates of regeneration of rrarw-azobenzene are subject to an isokinetic relationship with β = 328 K. These results indicate that photoinduced cis-trans isomerism of azobenzene, which has been found in former days, is useful as a new tool to enforce the conformational changes of crown ethers and polymers. The findings provide a possibility of controlling chemical functions of crown ethers and polymers by light.

Original languageEnglish
Pages (from-to)5860-5865
Number of pages6
JournalJournal of the American Chemical Society
Volume102
Issue number18
DOIs
Publication statusPublished - Jan 1 1980

Fingerprint

Isomerism
Crown Ethers
Crown ethers
Azobenzene
Polymers
Ammonium Compounds
Cations
Regeneration
Salts
Positive ions
azobenzene
Entropy
Ions
Light

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Photoresponsive Crown Ethers. 1. Cis-Trans Isomerism of Azobenzene as a Tool to Enforce Conformational Changes of Crown Ethers and Polymers. / Shinkai, Seiji; Nakaji, Takahiro; Nishida, Yoshihiro; Ogawa, Toshiyuki; Manabe, Osamu.

In: Journal of the American Chemical Society, Vol. 102, No. 18, 01.01.1980, p. 5860-5865.

Research output: Contribution to journalArticle

Shinkai, Seiji ; Nakaji, Takahiro ; Nishida, Yoshihiro ; Ogawa, Toshiyuki ; Manabe, Osamu. / Photoresponsive Crown Ethers. 1. Cis-Trans Isomerism of Azobenzene as a Tool to Enforce Conformational Changes of Crown Ethers and Polymers. In: Journal of the American Chemical Society. 1980 ; Vol. 102, No. 18. pp. 5860-5865.
@article{553fa67e50a548ebb2e8a9ba97aaffbc,
title = "Photoresponsive Crown Ethers. 1. Cis-Trans Isomerism of Azobenzene as a Tool to Enforce Conformational Changes of Crown Ethers and Polymers",
abstract = "An azobenzene-bridged crown ether (2) and a polymer containing both crown ether unit and azobenzene unit (4) were synthesized. 2 bridged with trans-azobenzene (trans-1) bound an ammonium cation (5) and methyl orange salts of Li+ and Na+ preferably, whereas 2 bridged with photo- (UV) isomerized cA-azobenzene (cis-2) bound methyl orange salts of K+ and Rb+ preferably. The result was rationalized in terms of photoinduced expansion of the crown ether size. The binding ability of polymer 4 was also subject to photoirradiation. In particular, the crown ether units adjoining the cA-azobenzene unit lost the affinity toward Na+ ion. The conformational changes of the crown ether and the polymer were conveniently monitored by following the spontaneous regeneration of trans-azobenzene in the dark. It was established on the basis of the rate measurements that (i) the conformational fluctuation of the crown ether is suppressed by K+ and ammonium cations, (ii) the extension of the polymer chain in solution accompanies a large entropy increase, and (iii) ∆H* and ∆S* for the rates of regeneration of rrarw-azobenzene are subject to an isokinetic relationship with β = 328 K. These results indicate that photoinduced cis-trans isomerism of azobenzene, which has been found in former days, is useful as a new tool to enforce the conformational changes of crown ethers and polymers. The findings provide a possibility of controlling chemical functions of crown ethers and polymers by light.",
author = "Seiji Shinkai and Takahiro Nakaji and Yoshihiro Nishida and Toshiyuki Ogawa and Osamu Manabe",
year = "1980",
month = "1",
day = "1",
doi = "10.1021/ja00538a026",
language = "English",
volume = "102",
pages = "5860--5865",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "18",

}

TY - JOUR

T1 - Photoresponsive Crown Ethers. 1. Cis-Trans Isomerism of Azobenzene as a Tool to Enforce Conformational Changes of Crown Ethers and Polymers

AU - Shinkai, Seiji

AU - Nakaji, Takahiro

AU - Nishida, Yoshihiro

AU - Ogawa, Toshiyuki

AU - Manabe, Osamu

PY - 1980/1/1

Y1 - 1980/1/1

N2 - An azobenzene-bridged crown ether (2) and a polymer containing both crown ether unit and azobenzene unit (4) were synthesized. 2 bridged with trans-azobenzene (trans-1) bound an ammonium cation (5) and methyl orange salts of Li+ and Na+ preferably, whereas 2 bridged with photo- (UV) isomerized cA-azobenzene (cis-2) bound methyl orange salts of K+ and Rb+ preferably. The result was rationalized in terms of photoinduced expansion of the crown ether size. The binding ability of polymer 4 was also subject to photoirradiation. In particular, the crown ether units adjoining the cA-azobenzene unit lost the affinity toward Na+ ion. The conformational changes of the crown ether and the polymer were conveniently monitored by following the spontaneous regeneration of trans-azobenzene in the dark. It was established on the basis of the rate measurements that (i) the conformational fluctuation of the crown ether is suppressed by K+ and ammonium cations, (ii) the extension of the polymer chain in solution accompanies a large entropy increase, and (iii) ∆H* and ∆S* for the rates of regeneration of rrarw-azobenzene are subject to an isokinetic relationship with β = 328 K. These results indicate that photoinduced cis-trans isomerism of azobenzene, which has been found in former days, is useful as a new tool to enforce the conformational changes of crown ethers and polymers. The findings provide a possibility of controlling chemical functions of crown ethers and polymers by light.

AB - An azobenzene-bridged crown ether (2) and a polymer containing both crown ether unit and azobenzene unit (4) were synthesized. 2 bridged with trans-azobenzene (trans-1) bound an ammonium cation (5) and methyl orange salts of Li+ and Na+ preferably, whereas 2 bridged with photo- (UV) isomerized cA-azobenzene (cis-2) bound methyl orange salts of K+ and Rb+ preferably. The result was rationalized in terms of photoinduced expansion of the crown ether size. The binding ability of polymer 4 was also subject to photoirradiation. In particular, the crown ether units adjoining the cA-azobenzene unit lost the affinity toward Na+ ion. The conformational changes of the crown ether and the polymer were conveniently monitored by following the spontaneous regeneration of trans-azobenzene in the dark. It was established on the basis of the rate measurements that (i) the conformational fluctuation of the crown ether is suppressed by K+ and ammonium cations, (ii) the extension of the polymer chain in solution accompanies a large entropy increase, and (iii) ∆H* and ∆S* for the rates of regeneration of rrarw-azobenzene are subject to an isokinetic relationship with β = 328 K. These results indicate that photoinduced cis-trans isomerism of azobenzene, which has been found in former days, is useful as a new tool to enforce the conformational changes of crown ethers and polymers. The findings provide a possibility of controlling chemical functions of crown ethers and polymers by light.

UR - http://www.scopus.com/inward/record.url?scp=0000759589&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000759589&partnerID=8YFLogxK

U2 - 10.1021/ja00538a026

DO - 10.1021/ja00538a026

M3 - Article

AN - SCOPUS:0000759589

VL - 102

SP - 5860

EP - 5865

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 18

ER -