(1)Journal of the Korean Chemical Society 2003, Vol

전체 글

(1)Journal of the Korean Chemical Society 2003, Vol. 47, No. 4 Printed in the Republic of Korea.

(2) CIDEP EPR . (2003. 6. 13 ) EPR Investigation of the CIDEP observed in Photoinduced Reaction of Xanthone with Alcohol on Effect of Addition of Water and Acid Jung Sung Yang Division of Chemical Engineering, Kyungnam University, Masan 631-701 Korea (Received June 13, 2003). :. TM, PRM, RTPM. Keywords: Triplet Mechanism, Radical Pair Mechanism, Radical Triplet Pair Mechanism.

(3) . 3. Xn*(Xanthone). CIDEP(Chemically Induced Dynamic Electron Polarization) !"# $ %&. TR-EPR (Time Resolved-Electron Paramagnetic Resonance) ' () * *+ , -+. # /00 %&. 12 3, 45+ $67+8 9 :; <3 =2 >?<@ ketyl + 0, sodiumborohydrideA <3 cyclohexadienyl B C + D + EF -+ . +&. + G HIJ CIDEP '() K $L MN(net emissive) O E*/ AP QR(S TU V MN WX0 Y T U V Z , *T[ net polarization \;2 8 B] ^_) /`&. a QR Pb F cd CIDEP efgh +i, jkl %&. mn, opq efgh(Triplet Mechanism : TM) MN QR r"s Xn* *c tu *+(intersystem crossing: isc) ;v w xy T ^+&. zn, ST { efgh(Radical Pair Mechanism: RPM) E/A(Emmision/Absorption) QR w T@ |} 8B8 ^+&. + G ~i Xn* w 1-7. 8. 9. 3. 0. 3. '() MN 8B~ $ %&. W8 45

(4) + $L Z QR 8B~ TR-EPR '()2 ^"# /00 %&. +

(5) 337 nm 45; $67

(6) 45 (XnH) ; E/A* QR $67(HP) CIDEP '()2 /@x&. + c<3 + '() * E*/AQR"# w&. +^ 45+ ; w P! w&. WX0 + + Z QR EPR '()# ^+&. W8 cc

(7) QR ¡¢ *£ ¤¥ ¦d §¨&. +^ ©ªb P+ « ¬` K

(8) ¬ ®c ¯° ±w&. ²X EPR(Fourier Transform EPR: FT-EPR) TR-EPR T³/& ´ Y µA ´ ¶ '() K,· 0 %&. a TR-EPR w ¸u * ¹(time evolution) ºv »¼ TU M,2 ½ d §T |} EPR ¸W¾ ; =¿ KÀ Á<@ Âu¬"# Ã&c =¿ Ä Å¬` Æ ´ kÇ<È $ %&. +É + TR-EPR. 10-11. 432.

(9)

(10) CIDEP EPR . 433. |} Å »¼ FT-EPR 0 45; $6 7

(11) \T Êt 'Ë; Ì w Í#Î v/ H %Ã&. Å 45; 2-Ï#Ð7

(12) IÑ + c2 Òk<0, WX0 45; 2-Ï #Ð7 20% H O2 çÓ ÔÕ iÖA

(13) K, ; a + ç× | 'Ë QR 2 Âu FT-EPR2 i, ,Ø"# CIDEP Pbc ÙÚ`d2 $¯/D Û¬+ %&. 12. 2. FT-EPR ºv X-band '()#Ü(JEOL FE-3X) 2 0 Ý<Þ&.

(14) @T XeCl excimer + (Lambdaphysik EMG 103 MSC, 308 nm, 12 Hz ß à)2 0 »¼<Þ&. áâ(Free Induction Decay) ¸W¾ CYCLOPS2 i, HÃ&. FT-EPR ãä '() Fid(Free induction decay) Frourier HÃ&. WX0 EPR ¸W¾ ¸ u *¹ + ; å+æ# ãä ç'+ d ¸u ¸è"# ºv<Þ&. + »¼ KX ¸u ~3é10 s+0 + ê å+ æ#ãA + ç' ë; ç' ¸u ¦ # ìv<Þ&. CIDEP '() boxcar intergrator(PAR model 160) 2 i<@ Tí<Þ&. 45 vî<d § ï ¸ W# i<Þ 0, 2-Ï#Ð7 G.R ï ¸(Aldrich) i<Þ&. FT-EPR ºv ðñ iò~ = Æ= c'2 EPR cavity~ jów À¤ ô Á, õÏ# ¦Ç è"# î® ¸ö&. WX0

(15) '() P

(16) '()#Ü(Hitachi Model 850 a Shimadzu RF500) 0 ºv<Þ&. Z A MN »¼ 2-Ï#Ð7; < 45 ÷ 2.0é10 M+Ã&. WX0 cw ø 20% v/v +Ã&. WX0 ÷ 1.1 M i<Þ&. −8. −4. . ,

(17) Â w $67 iÖA + iÖ 20% çÓ 2003, Vol. 47, No. 4. Fig. 1. Effect of the addition of water on (a) absorption and (b) emission spectra of xanthone in 2-propanol. The concentration of xanthone was kept at 2.0×10−4 M. The excitation wavelength used for recording the emission spectra was 308 nm.. ù H Xn Z '()2 Fig. 1(a) 8B ú&. + Wû 20%(V/V) H O2 c, ü+æ c ® ý ^ /@¦0 %&. þ 2-Ï#Ð7 ç× | Z '() ¯ÙÉ rI8d §¨&. +^"#Ü 45 ©ªb u c, ¤¥ ½d §& ^ $. %Ã&. Fig. 1(b) ù ÿXw Xn; 2-Ï#Ð7; H

(18) '()+&. @T /3 ü+æ c 20% c# ` <@ Z '(); ¬"#

(19) '() J ^ %&. a 450 nm F ü+æc ,d3 ® < ^ . %&. 45 ©ª b c |} T Xn iÖ ¤¥ æÈ ½ ^ $ %&. &- Xn* $¯/T y<@ Âu Z » ¼ Ý<Þ&. Xn* Z '() 615 nm ê ^"# $ %&. Fig. 2(a) 615 nm Â w 2-Ï#Ð7; 10 M; 10 M 2. 3. 3. −2. −3.

(20) . 434. Fig. 2. Decay of the transient absorption at 615 nm observed upon photoexcitation of xanthone in 2-propanol. (a) Xanthone concentration dependence of the decay, (b) Effect of addition of 20 water.. ÷2 45;

(21) K, Âu Z. áâ

(22) /@x ^+&. +

(23) /3 áâc rI8 ^ $ %&. +^ Xn* + iÖ K#Ü H2 >?!"# XnH w Z |}"# %&. Â w 2-Ï#Ð7; 10 M 45; 3.2é10 s à 2 &. W8 20% !w 2Ï#Ð7; 10 M 45; Fig. 2(b) /©A G+ opq áâ àc 1.2é10 s # Ç`Ã&. W# Âu Z cl |c c<d § |/& áâ àc ^ $ % Ã&. (1) 45; $67 8B] ^+&. X*PrOH → · XnH · PrOH (1) Xn* áâà , kHA Xn* ¦y iÖ ! $ %&. w iÖ 3(nπ*)/& 3 (ππ*) dc ´ ST |} = >? àc J&0 . %&. FT-EPR

(24) 308 nm + , 45; 2-Ï#Ð7; FT-EPR'() Fig. 3. −3. 6. −3. 6. kHA. 3. 3. 3. 14-15. −1. −1. Fig. 3. FT-EPR spectra of free radicals formed by photolysis of xanthone (1.0×10−2 M) observed for a delay time of 60 ns after the laser pulse, (a) in neat 2-propanol, (b) in a 2-propanol with 20 water.(c) in 2-propanol with 20% water and 1.1 M HBr. The arrows mark the resonance peaks due to 2 HP.. 8Bú&. '() S0 Y ø TU 1Xw w

(25) 2 HP , 8B ^ +0 '() p &p

(26) ¸W¾ (1) ; ró< Xanthone Ketyl(XnH) , 8B ^+&. + '() ST RPM , E/ A d¬` T@# `<@ E/A* QR /@x ^+ &. WX0 $L EK TM CIDEP ^+&. MN ¸W¾ r"× % opq efgh TM .c S iò 45 opq TR-EPR ºv "#Ü HÃ&. Fig. 3(a) H QR Pb ãU 3(a). 0. Journal of the Korean Chemical Society.

(27)

(28) CIDEP EPR . &&. + G » 337 nm + +iw 45 &

(29) K, P TR-EPR }; <@ $ %Ã&. Å » ¼ "# XeCl excimer + 308 nm2 i, H TR-EPR '() FT-EPR »¼óA r ó<Þ0 E*/A /Þ&. W8 355 nm H B »¼ E/A* BC /Þ &. +^"#Ü Xn; 2-Ï#Ð7

(30) K, '() CIDEP Pb ãU w& » $ %Ã&. Fig. 3(b) / ©A G+ 45; 2-Ï#Ð7; c<3 ¸W¾ c µ=<0 CIDEP Pb u < ^ $ %&. a + '() + ý Fig. 3(a)A <3 + % | ´ kÇw E*/A /@ ¦ ^ $ %&. 20% !w 45; $67 çs3 Fig. 3(c) / ©A G+ CIDEP ¡ ¢+ <È w&. þ + FT-EPR'() ì E*/A E/A*# © /@¦0 %&. + t !"# " ¸W¾ $L Z ¸ W¾ efgh+ %0 a # ¸W¾ K RPM"#Ü efgh+ $w&0 . %&. 17. 45; 2-Ï#Ð7;

(31) Xanthone ketyl(XnH) ; 2-hydroxypropan-2-yl(2 HP) ` ^ $ %Ã&. 45; 2-Ï#Ð7 iò ç× | ¸W¾ c µ=<%, CIDEP ¡¢ ` + Ã&. + '() + ý |A <3 + % | ´ &'w E*/A w ¡¢ /@¦Ã&. þ, c# `w iÖ (; |}`^$ %Ã&. 20% H O2 $67; 45 iò c<3 CIDEP ¡¢ w `+ &. WX0 + '() /& w E/A *) ¬"# /@¦0 %d, !"#, Â Z ¸W¾ T@2 d< CIDEP efgh+ + t %& ^+&. WX0 # ¸W¾ K RPM"# Ü w ^"# %&. Â w 2-propanol; 10 M; 10 M 45

(32) K 2. −2. 2003, Vol. 47, No. 4. −3. 435. , Âu Z áâ

(33) - . áâc rI&. +^ iÖ K#Ü H >?# XnH w Z |}"# %&. opq áâ à 1.2é10 s # Ç`Ã"% Â u Z cl |c c<d § |/& á â àc ^ $ %&. !w 45; 2-Ï#Ð7; çs3

(34) + Â Z QR"# ©* ^ $. %Ã&. CIDEP Pb »¼ Á, opq efgh(TM); opq 9I efgh(RTPM)"#Ü u T @ ¦# S-To 9I efgh(RPM) w ^ $ %Ã&. 6. −1. Å 2002+ ³ , ÝÃ"% + µ2 ,g&..

(35) 1. J. S. Yang, N. Hirota, Y. Kitahama, J. Phys. Chem. A. 2000, 104, 5928 2. J. S. Yang, J. Basic Science. 2001, 15, 41. 3. K. Tominaga, S. Yamauchi, N. Hirota. J. Chem. Phys. 1990, 92, 5175. 4. N. Ishiwata, H. Murai, K. Kuwata, R es. Chem. Intermed. 1993, 19, 59. 5. K. Ohara, N. Hirota, Bull. Chem. Soc. Jpn.. 1996, 69, 1517. 6. H. van Willigen, H. P. Levstein, R. M. Ebersile, Chem. Rev. 1993, 93, 173. 7. A. Kawai, T. Okutsu, K. Obi, J. Phys. Chem, 1991, 95, 9130. 8. P. R. Levstein, H. van Willigen, J. Chem. Phys. 1991, 95, 900. 9. K. Ohara, N. Hirota, C. A. Steren, H. van Willigen, Chem. Phys. Lett. 1995, 232, 169. 10. J. S. Yang, Environmental Research 2000, 23, 115. 11. A. Kawao, K. Obi, J. Phys. Chem. 1992, 96, 5701. 12. S. Michaeli, V. Meiklyar, M. Schulz, K. Möbius, H. Levanon, J phys. Chem. 1994, 96, 7444. 13. J. S. Yang, Theses Collection. 2001, 19, 93. 14. K. Katsuki, K. Akiyama, S. Tero- Kubota, Bull. Chem. Soc. Jpn. 1995, 68, 3383. 15. H. Murai, M. Minami, Y.J. Ihaya, J. Chem Phys. 1994, 101, 4514. 16. A. Kawai, T. Okutsu, K. Obi, Chem. Phys. Lett. 1990, 174, 213..

(36) 436 17. M. Baba, T. Kamei, M. Kiritani, S. Yamauchi, N. Hirota, Chem. Phys. Lett. 1991, 185, 354. 18. H. Murai, K. Kuwata, J. Phys. Chem. 1991, 95, 9247. 19. J. J Cavaleri, K. Prater, R. M. Bo wman, Chem. Phys. Lett. 1996, 259, 495. 20. J. S. Yang, Environmental Research 2000, 23, 115. 21. C. Blättler, F. Jent, H. Paul, Res. Chem. intermed. 1991, 16, 201.. 22. K. Katsuki, K. Akiyama, Y. Ikegami, S. T. Kubota, J. Am. Chem. soc. 1994, 116, 12065. 23. H. Murai, M., Minami, Y. J. IHaya, J. Phys. Chem. 1988, 92, 2120. 24. K. Ohara, H. Murai, Bull. Chem. Soc. Jpn. 1989, 62, 2435. 25. J. S. Yang, J. Theses Collection. 2002, 20, 161.. Journal of the Korean Chemical Society.

(37)