An ionic cascade insertion/cyclization reaction of thia-/selena-functionalized arylisocyanides has been successfully developed for the efficient and practical synthesis of 2-halobenzothiazole/benzoselenazole derivatives. This synthetic protocol, incorporating a halogen atom when forming the five-membered ring of benzothia/selenazoles, is different from the existing ones, where halogenation of the preformed
Facile Rearrangements of Alkynylamino Heterocycles with Noble Metal Cations
作者:Roger Lok、Ronald E. Leone、Antony J. Williams
DOI:10.1021/jo952101z
日期:1996.1.1
A number of 2-(alkynylamino)-substituted heterocycles have been synthesized. These heterocycles rearrange in the presence of silver(I) and gold(I) salts to give novel 2H-pyrimido[2,1-b]benzoxazoles, 2H-pyrimido[2,1-b]benzothiazoles, and a 2H-pyrimido[2,1-b]benzoselenazole. Two of the the 2H-pyrimido[2,1-b]benzoxazoles were isolated in good yield. The kinetics of the silver tetrafluoroborate-catalyzed rearrangements of selected (alkynylamino)benzoxazoles and benzothiazoles have been examined by H-1 NMR in CD3CN. Factors affecting the electron densities of the triple bond and of the nitrogen atom in the heterocycle are important in influencing the rate of rearrangement.
The Synthesis of Polyazaindenes and Related Compounds
作者:G. A. REYNOLDS、J. A. VanALLAN
DOI:10.1021/jo01092a023
日期:1959.10
Balli,H.; Kersting,F., Justus Liebigs Annalen der Chemie, 1961, vol. 647, p. 1 - 10