Portal de Periódicos da CAPES

Functional monomers and polymers. LXI. Photochemical reactions on the synthetic polymers containing thymine bases

1980; Wiley; Volume: 18; Issue: 2 Linguagem: Inglês

10.1002/pol.1980.170180203

1542-9369

Yasuo Kita, Yoshiaki Inaki, Kiichi Takemoto,

Synthesis and properties of polymers

Abstract Photodimerization of N ‐2‐isobutyloxyethyl thymine (T‐M), bis[2‐(5‐methyl‐1‐primidinyl)‐ethyl] glutarate (T‐T), poly( N ‐2‐methacryloyloxyethyl thymine) (polyMAOT), and poly( N ‐2‐acryloyloxyethyl thymine) (poly AOT) was studied in dimethylformamide solution. The rate of intramolecular photodimerization of polyMAOT and polyAOT was 5.7 and 7.2 times faster, respectively, than that of T‐T. In T‐M, however, intermolecular photodimerization did not occur under the reaction condition used. Quenching studies with isoprene suggest that the photodimerization of T‐T occurs predominantly in an excited triplet state, whereas that of polyMAOT and polyAOT occur in singlet and triplet states. It was concluded that the photodimers of T‐T, polyMAOT, and polyAOT are two syn‐fused cyclobutane‐type dimers (cis‐syn and trans‐syn). Quantum efficiencies of thymine base disappearance were determined by ultraviolet (UV) analysis to be 0.0012 for T‐T, 0.0084 for polyMAOT, and 0.010 for polyAOT.