SYNTHESIS OF [POLY(2-PYRIDYL)-SUBSTITUTED]-1-AZAAZULENES

• Published in: Heterocycles Vol. 77; no. 1; pp. 565 - 574
• Main Authors: Ariyoshi, Tornoyuki, Noda, Tornonori, Watarai, Satorni, Tagashira, Shoji, Murakami, Yoshiko, Fujii, Hiroyuki, Abe, Noritaka
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier 01.01.2009
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; 3,3 '-Bi(1-azaazulene); Iodo-1-azaazulene; (2-Pyridyl)-1-azaazulene; Addition-Elimination; Suzuki Coupling
• ISSN: 0385-5414; 1881-0942
• DOI: 10.3987/COM-08-S(F)8

2-(2-Pyridyl)-1-azaazulenes were derived from 2-bromo- or 2-iodo-1-azaazulenes and 3-(2-pyridyl)-1-azaazulenes were derived from 3-iodo-1-azaazulenes by Suzuki coupling. Reaction of 3-iodo-1-azaazulenes with B(NPDEA) gave corresponding 3-(2-pyridyl)-1-azaazulenes together with 3-borylated-2-chloor-1-azaazulene (9a) or 3,3'-bi(2-methoxy-1-azaazulene) (10b). Reactions of 8-(2-pyridyl)-1-azaazulene with 2-pyridyllithium gave 4,8-di(2-pyridyl)- and 6,8-di(2-pyridyl)-1-azaazulenes. Reactions of 4,8-di(2-pyridyl)-1-azaazulene with 2-pyridyl lithium gave 4,6,8-tri(2-pyridyl)-1-azaazulene. The reactivity of the seven-menbered ring is C8 > C6 > C4. Reaction of 3-(2-pyridyl)-1-azaazulenes with 2-pyridyllithium gave 3,4-di(2-pyridyl)- and 3,8-di(2-pyridyl)-1-azaazulenes.