I. Dix, Christian Doll, H. Hopf
Aug 1, 2002
Citations
0
Influential Citations
19
Citations
Journal
European Journal of Organic Chemistry
Abstract
4-(2-Ethynylphenyl)pyridine (10), 3-(2-ethynylphenyl)pyridine (11), 2-(2-trimethylsilylethynylphenyl)pyridine (26), and 3-ethynyl-2-phenylpyridine (13) were prepared from readily available pyridine precursors by standard coupling reactions. Pyrolysis of 10 at 810 °C/0.5 Torr provided benzo[f]isoquinoline (45) and the benzopentalene dimer 47. Pyrolysis of 11 (820 °C/0.5 Torr) afforded benzo[f]quinoline (50), benzo[h]isoquinoline (52), and a mixture of isomers of 47. Pyrolysis of 13 (820 °C/0.3 Torr) provided benzo[h]quinoline (56) and the novel azulene derivative azuleno[1,2-b]pyridine (58). When 26 was desilylated by treatment with TBAF in THF/water, the unusual “dimerization” product 37 was produced; its structure was confirmed by X-ray structural analysis. The mechanisms of these transformations are discussed. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)