1629167-75-4Relevant academic research and scientific papers
Facile synthesis of heavily-substituted alkynylpyridines via a Sonogashira approach
Kelgokmen, Yilmaz,Zora, Metin
, p. 4608 - 4621 (2016/01/29)
A facile and efficient synthetic route to densely substituted alkynylpyridines via a Sonogashira approach is reported. When treated with terminal alkynes in the presence of 5 mol% PdCl2(PPh3)2, 5 mol% CuI and excess Etsub
Transition-metal-free BF3-mediated oxidative and non-oxidative cross-coupling of pyridines
Chen, Quan,Leon, Thierry,Knochel, Paul
supporting information, p. 8746 - 8750 (2014/08/18)
We report a BF3-mediated direct alkynylation of pyridines at C(2) by using a variety of alkynyllithium reagents (oxidative cross-coupling). Moreover, we have developed a novel transition-metal-free cross-coupling method between alkylmagnesium reagents and 4-substituted pyridines, such as isonicotinonitrile and 4-chloropyridine, by employing BF3· OEt2 as a promoter. The combination of these methods enabled us to efficiently prepare a range of di-, tri-, and tetrasubstituted pyridines. Oxidative or non-oxidative - That is the question! Pyridines bearing a substituent at position 4 readily undergo a BF3-mediated oxidative coupling at position 2 with a wide range of alkynyllithium compounds. In contrast, 4-cyano- or 4-chloropyridines undergo a novel BF3-mediated cross-coupling at position 4 with alkylmagnesium reagents. The combination of the two transition-metal-free procedures allows the preparation of a broad range of pyridines.
