Pyrimidine-core extended pi-systems: general synthesis and interesting fluorescent properties.
We have developed a simple but powerful synthetic strategy that permits the assembly of pi-systems onto a pyrimidine core in a programmable and diversity-oriented format. The nucleophilic addition of ArLi to 2-methylthiopyrimidine, followed by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) oxidation, resulted in the production of 4-aryl-2-methylthiopyrimidines. The iterative reaction sequence then gave 4,6-diaryl-2-methylthiopyrimidines. The resulting adduct was further allowed to react with ArMgBr under the catalytic influence of NiCl2(dppe) to afford 2,4,6-triarylpyrimidines. By following this synthetic scheme, interesting pyrimidine-core pi-systems were rapidly constructed in a programmable fashion. The successful discovery of a number of interesting fluorescent materials and properties (e.g., solvatofluorochromism) speaks well for the potential of our platform strategy in the development of functional organic materials.
Itami
Kenichiro
K
Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan. itami@sbchem.kyoto-u.ac.jp
Yamazaki
Daisuke
D
Yoshida
Jun-ichi
J