Abstract
Synthesis and spectral properties of cyanine dyes 1 and 2, having julolidinylethenyl and α-methyl julolidinylethenyl moieties respectively at the meso position, are described. In comparison with planer 1, the methyl group of the julolidinylethenyl group in 2 prevents the coplanarity of the whole dye system. Their characteristic electronic absorption spectra are analyzed based on the molecular orbital calculations, and the calculations well reproduce the observed data. Analysis of 1H NMR spectrum of 1 indicates that the π-electrons in the julolidinylethenyl group shift toward the cyanine main chromophore through the π-conjugation. Intramolecular charge transfer from the julolidine moiety to the cyanine main chromophore contributes to lightfastness of dyes. These findings make it possible to design a new type of stable cyanine dyes against photoirradiation with new functionalities such as intramolecular charge transfer system.
| Original language | English |
|---|---|
| Pages (from-to) | 113-120 |
| Number of pages | 8 |
| Journal | Dyes and Pigments |
| Volume | 54 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Aug 2002 |
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Keywords
- Electron donor
- Intramolecular charge-transfer
- Julolidinylethenyl group
- Meso-substituted cyanine
- New functional dye
- Trimethine cyanine
ASJC Scopus subject areas
- Chemical Engineering(all)
- Process Chemistry and Technology
Cite this
Spectroscopic properties of meso-substituted cyanine dyes : Evidences for intramolecular charge transfer from a julolidine moiety as a meso-substituent to the cyanine chromophore. / Mitekura, Hirofumi; No, Tomoko; Suzuki, Kazuyoshi; Satake, Kyosuke; Kimura, Masaru.
In: Dyes and Pigments, Vol. 54, No. 2, 08.2002, p. 113-120.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Spectroscopic properties of meso-substituted cyanine dyes
T2 - Evidences for intramolecular charge transfer from a julolidine moiety as a meso-substituent to the cyanine chromophore
AU - Mitekura, Hirofumi
AU - No, Tomoko
AU - Suzuki, Kazuyoshi
AU - Satake, Kyosuke
AU - Kimura, Masaru
PY - 2002/8
Y1 - 2002/8
N2 - Synthesis and spectral properties of cyanine dyes 1 and 2, having julolidinylethenyl and α-methyl julolidinylethenyl moieties respectively at the meso position, are described. In comparison with planer 1, the methyl group of the julolidinylethenyl group in 2 prevents the coplanarity of the whole dye system. Their characteristic electronic absorption spectra are analyzed based on the molecular orbital calculations, and the calculations well reproduce the observed data. Analysis of 1H NMR spectrum of 1 indicates that the π-electrons in the julolidinylethenyl group shift toward the cyanine main chromophore through the π-conjugation. Intramolecular charge transfer from the julolidine moiety to the cyanine main chromophore contributes to lightfastness of dyes. These findings make it possible to design a new type of stable cyanine dyes against photoirradiation with new functionalities such as intramolecular charge transfer system.
AB - Synthesis and spectral properties of cyanine dyes 1 and 2, having julolidinylethenyl and α-methyl julolidinylethenyl moieties respectively at the meso position, are described. In comparison with planer 1, the methyl group of the julolidinylethenyl group in 2 prevents the coplanarity of the whole dye system. Their characteristic electronic absorption spectra are analyzed based on the molecular orbital calculations, and the calculations well reproduce the observed data. Analysis of 1H NMR spectrum of 1 indicates that the π-electrons in the julolidinylethenyl group shift toward the cyanine main chromophore through the π-conjugation. Intramolecular charge transfer from the julolidine moiety to the cyanine main chromophore contributes to lightfastness of dyes. These findings make it possible to design a new type of stable cyanine dyes against photoirradiation with new functionalities such as intramolecular charge transfer system.
KW - Electron donor
KW - Intramolecular charge-transfer
KW - Julolidinylethenyl group
KW - Meso-substituted cyanine
KW - New functional dye
KW - Trimethine cyanine
UR - http://www.scopus.com/inward/record.url?scp=0036672294&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036672294&partnerID=8YFLogxK
U2 - 10.1016/S0143-7208(02)00023-2
DO - 10.1016/S0143-7208(02)00023-2
M3 - Article
AN - SCOPUS:0036672294
VL - 54
SP - 113
EP - 120
JO - Dyes and Pigments
JF - Dyes and Pigments
SN - 0143-7208
IS - 2
ER -