Radiation induced racemization of 1,1'-binaphthyl in tetrahydrofuran and toluene. [. gamma. -rays]

Journal Article · Thu May 19 04:00:00 EDT 1977 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100525a010· OSTI ID:7324414

Irie, M; Yorozu, T; Yoshida, K; Hayashi, K

Radiation-induced racemization of 1,1'-binaphthyl has been studied in tetrahydrofuran and toluene. The effect of additives proved that the racemization reaction in tetrahydrofuran occurs mainly in a radical anion state of 1,1'-binaphthyl, while in toluene the reaction occurs mainly in the triplet excited state. The low activation energies of the reaction in both solvents, 1.1 kcal/mole in tetrahydrofuran and 1.9 kcal/mole in toluene, as compared to thermal racemization indicate that the introduction of an electron to the lowest vacant molecular orbital causes an electronic structure change favorable to rotation along the intraannular C--C bond. The conformational change in the radical anion state is directly followed by the measurement of the absorption spectrum change at a low temperature. The concentration dependence of the G value of the racemization in both solvents clearly indicates a chain reaction with chain carriers of the radical anion state in tetrahydrofuran and the triplet excited state in toluene. The chain reaction via the triplet excited state in toluene gives a G value as high as 30.

• Research Organization: Osaka Univ., Suita, Japan
• OSTI ID: 7324414
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 81:10; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
AROMATICS
CHEMICAL RADIATION EFFECTS
CHEMISTRY
ELECTROMAGNETIC RADIATION
G VALUE
GAMMA RADIATION
HYDROCARBONS
IONIZING RADIATIONS
ORGANIC COMPOUNDS
QUANTITY RATIO
RACEMIZATION
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS