Self-assembled boronic ester cavitand capsule as a photosensitizer and a guard nanocontainer against photochemical reactions of 2,6-diacetoxyanthracene.
The optical properties of 2,6-diacetoxyanthracene 4 encapsulated in the self-assembled boronic ester cavitand capsule 3 in C(6)H(6) are described. Upon excitation at 285 nm, the encapsulated 4 showed strong fluorescence emission as a result of the energy transfer from the excited 3 to the encapsulated 4, while 4 alone in C(6)H(6) exhibited very weak emission. Upon photoirradiation at 365 nm, the encapsulated 4 also showed strong fluorescence emission and remained almost intact, whereas 4 alone in C(6)H(6) gradually underwent photodimerization and photooxygenation to afford photodimers 5 and 5' and 9,10-anthraquinone 6 via 9,10-endoperoxide 7, respectively. Thus, the capsule 3 serves as a photosensitizer for the encapsulated 4 as well as a guard nanocontainer to protect against the photochemical reactions of 4.
Nishimura
Naoki
N
Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
Kobayashi
Kenji
K
D000873:Anthracenes / Q000737:chemistry*; D001897:Boronic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D005453:Fluorescence; D008958:Models, Molecular; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D010777:Photochemistry; D017319:Photosensitizing Agents / Q000138:chemical synthesis* / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
C554800:2,6-diacetoxyanthracene; D000873:Anthracenes; D001897:Boronic Acids; D004952:Esters; D017319:Photosensitizing Agents