134643-15-5Relevant academic research and scientific papers
Synthesis of Trisubstituted Pyridines via Chemoselective Suzuki–Miyaura Coupling of 3,5- and 4,6-Dibromo-2-tosyloxypyridines
Park, Cho-Hee,Kwon, Yong-Ju,Oh, In-Young,Kim, Won-Suk
, p. 107 - 119 (2017)
Chemoselective Suzuki–Miyaura reactions on 3,5- and 4,6-dibromo-2-tosyloxypyridines have been studied for the preparation of trisubstituted pyridines. The optimized conditions allow for a facile access to 3,5- and 4,6-diaryl-2-tosyloxypyridines in yields of 8 to 99%. Further functionalization such as palladium-catalyzed amination and copper-free Sonogashira reaction of the tosylate group in the diarylpyridine derivatives obtained was accomplished for the synthesis of novel and biologically relevant trisubstituted pyridines. The formal synthesis of ficuseptine, a bioactive alkaloid, has also been achieved via the palladium-catalyzed cross-coupling reaction of 3,5-dibromo-2-tosyloxypyridine in 5 steps from 3,5-dibromo-2-hydroxypyridine with 50% overall yield. (Figure presented.).
On the Reaction of (Vinylimino)phosphoranes. Part 17. Preparation of N-Vinylcarbodiimides and Their Cycloaddition with Several Dienophiles to Give Pyridine Ring System
Nitta, Makoto,Soeda, Hironobu,Koyama, Shinya,Iino, Yukio
, p. 1325 - 1331 (2007/10/02)
The aza-Wittig reaction of (vinylimino)triphenylphosphorane and its several derivatives was examined to give N-phenyl-N'-vinylcarbodiimide and its derivatives, all of which underwent a cycloaddition reaction with electron-rich dienophiles (enamines) and/or electron-deficient dienophiles (activated acetylenes), resulting in the formation of a pyridine ring system.The regioselectivity of the cycloaddition reaction could be rationalized on the basis of a frontier orbital consideration.
