6-Hydroxy-2,2,5,7,8-pentamethylchroman Singlet oxygen

Mukai, K.; Daifuku, K.; Okabe, K.; Tanigaki, T.; Inoue, K.
J. Org. Chem. 56, 4188-4192 (1991)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: EtOH

k = 2.0 × 10⁸(L mol^-1 s^-1), T = 308K

Experimental method: Chemical reaction
Analytical method: vis-UV absorption
Data type: Derived from steady state measurements using indicator

Indicator = 1,3-Diphenylisobenzofuran; used solvent k_d = 8.3 × 10⁴ s^-1; ¹O₂* from MNPO₂. [Indicator] = 4.3 × 10^-5 (mol L^-1).

Li, G.; He, S.; Shi, J.; Zhang, J.
Huadong Huagong Xueyuan Xuebao 17, 431-436 (1991)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products
Reference Reaction: DPBF + ¹O₂^* ®
Solvent: MeOH

k_react = 4.0 × 10⁷(L mol^-1 s^-1), k_reference = 8 × 10⁸(L mol^-1 s^-1)

Experimental method: Photolysis
Analytical method: HPLC
Data type: Relative value measured by steady state method

Photosensitizer = Methylene Blue.

Li, G.; He, S.; Shi, J.; Zhang, J.
Huadong Huagong Xueyuan Xuebao 17, 431-436 (1991)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: MeOH

k = 1.6 × 10⁸(L mol^-1 s^-1)

Experimental method: Photolysis
Analytical method: vis-UV emission
Data type: Derived from steady state measurements using indicator

Photosensitizer = Methylene Blue; Indicator = 1,3-Diphenylisobenzofuran. used solvent k_d = 1.8 × 10⁵ s^-1.

Gorman, A.A.; Gould, I.R.; Hamblett, I.; Standen, M.C.
J. Am. Chem. Soc. 106, 6956-6959 (1984)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: Cyclohexane

Enthalpy of activation = 0.0(kJ mol^-1), Entropy of activation = -130(J K^-1 mol^-1), Temperature range 278 to 357 K
k = 2.4 × 10⁷(L mol^-1 s^-1)

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator

Photosensitizer = 2'-Acetonaphthone; Indicator = 1,3-Diphenylisobenzofuran.

Gorman, A.A.; Gould, I.R.; Hamblett, I.; Standen, M.C.
J. Am. Chem. Soc. 106, 6956-6959 (1984)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: Toluene

Enthalpy of activation = -15(kJ mol^-1), Entropy of activation = -138(J K^-1 mol^-1), Temperature range 230 to 385 K
k = 1.5 × 10⁸(L mol^-1 s^-1)

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator

Photosensitizer = 2'-Acetonaphthone; Indicator = 1,3-Diphenylisobenzofuran.

Gorman, A.A.; Gould, I.R.; Hamblett, I.; Standen, M.C.
J. Am. Chem. Soc. 106, 6956-6959 (1984)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: Acetonitrile

Enthalpy of activation = -15(kJ mol^-1), Entropy of activation = -130(J K^-1 mol^-1), Temperature range 230 to 357 K
k = 5.7 × 10⁸(L mol^-1 s^-1)

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator

Photosensitizer = 2'-Acetonaphthone; Indicator = 1,3-Diphenylisobenzofuran.

Gorman, A.A.; Gould, I.R.; Hamblett, I.; Standen, M.C.
J. Am. Chem. Soc. 106, 6956-6959 (1984)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: Acetone

Enthalpy of activation = 0.0(kJ mol^-1), Entropy of activation = -109(J K^-1 mol^-1), Temperature range 250 to 328 K
k = 2.6 × 10⁸(L mol^-1 s^-1)

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator

Photosensitizer = 2'-Acetonaphthone; Indicator = 1,3-Diphenylisobenzofuran.

Gorman, A.A.; Gould, I.R.; Hamblett, I.; Standen, M.C.
J. Am. Chem. Soc. 106, 6956-6959 (1984)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: Methanol

Enthalpy of activation = 0.0(kJ mol^-1), Entropy of activation = -100(J K^-1 mol^-1), Temperature range 250 to 328 K
k = 3.4 × 10⁸(L mol^-1 s^-1)

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator

Photosensitizer = 2'-Acetonaphthone; Indicator = 1,3-Diphenylisobenzofuran.

Lindig, B.A.; Rodgers, M.A.J.
Photochem. Photobiol. 33, 627-634 (1981)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: D₂O (mic)

k = 4.1 × 10⁸(L mol^-1 s^-1), pH = 7.4, T = 294K

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator
Excitation wavelength: 337 nm

Photosensitizer = Methylene Blue; Indicator = 1,3-Diphenylisobenzofuran; 0.1 mol L^-1 CTAB. [Sensitizer] = 2.6 × 10^-5 (mol L^-1). [Indicator] = 2.3 × 10^-5 (mol L^-1).

Lindig, B.A.; Rodgers, M.A.J.
Photochem. Photobiol. 33, 627-634 (1981)

Reaction: 6-Hydroxy-2,2,5,7,8-pentamethylchroman + ¹O₂^* ® products and/or physical quenching
Solvent: D₂O (mic)

k = 4.0 × 10⁸(L mol^-1 s^-1), pH = 7.4, T = 294K

Experimental method: Flash photolysis
Analytical method: vis-UV absorption
Data type: Absolute value measured directly using indicator
Excitation wavelength: 337 nm

Photosensitizer = Methylene Blue; Indicator = 1,3-Diphenylisobenzofuran; 0.1 mol L^-1 SDS. [Sensitizer] = 2.6 × 10^-5 (mol L^-1). [Indicator] = 2.3 × 10^-5 (mol L^-1).