The Photochemical Behaviors of trans-4-Alkoxy-4'-Stilbazole and Its Hydrochloric salt
1993
Hochschulschrift
Zugriff:
81
The photoisomerization(trans=cis) and photocyclodimer- ization( monomer.arrr.dimer) oftrans-4-alkoxy-4'-stilbazole (CnOSP, with n=1 and 4)and its HCl salt(HClCnOSP) were studied (irradiated with wave-length >320nm) by UV-VIS,NMR and FT-IR spectroscopic methods. The NMR results showed that the photostationary state of C(1)OSP/CDCl solution consisted of trans:cis: dimer=20 :62 :18 mole %, with k(1)=3.27*0.01/min,k(-1)= 1.048*0.01/min and k(2)=7*0.001(concentration/min). That of HClC(1)OSP/CDCl solution gave trans:cis=38:62mole%, without dimer formation, and k and kwere3.45*0.1/min and 2.1*0.1/min,respectively. A complete conversion from trans to dimer was observed for HClC(1) OSP/Deuterium oxide solution from NMR studies.However,signals related to cis-form were observed during the irradiation. The rate constants were k(1)=5* 0.01/min,k(-1)=1*10(-10)/min and k(2)=4.25 (concentration/min). The results obtained for dyes dissolved in CTAB micelle solutions were comparable to those in pure Deuterium oxide (or HO) solvent, from both NMR and UV-VIS studies. How- ever,the ratio of trans:cis:dimer = 20.0 :29.1 :42.9 mole%, was obtained for dyes dissolved in SDS micelle solutions. For the cyclodextrin (CDX) solutions,.beta.-CDX gave trans:cis:dimer =19.37 :73.23 :7.5 mole%, and .gamma. -CDX gave complete conversion to dimer. These variations were attributed to the constraints imposed on the solute molecules by the solvents.
Titel: |
The Photochemical Behaviors of trans-4-Alkoxy-4'-Stilbazole and Its Hydrochloric salt
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Autor/in / Beteiligte Person: | Chang, Cheng-Chung ; 張健忠 |
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Veröffentlichung: | 1993 |
Medientyp: | Hochschulschrift |
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