Study on selectivity in the reaction of 2-substituted pyridinium-N-imines with dimethyl acetylenedicarboxylate was written by Supranovich, Vyacheslav I.;Vorob’ev, Aleksey Yu.;Borodkin, Gennady I.;Gatilov, Yury V.;Shubin, Vyacheslav G.. And the article was included in Tetrahedron Letters in 2016.Application In Synthesis of 2-Phenoxypyridine This article mentions the following:
Reactions of 2-X-pyridinium-N-imines (X = F, Cl, Br, CN, OPh, NH2, N-morpholine) with di-Me acetylenedicarboxylate (DMAD) were studied. In the case of X = Cl, Br, CN, OPh both 7-substituted- and 7-H-pyrazolo[1,5-a]pyridines are formed. The 7-H/7-X ratio usually increases with the growing solvent polarity. The reaction of N-amino-2-iminopyridine with DMAD gives substituted pyrido[1,2-b][1,2,4]triazine. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Application In Synthesis of 2-Phenoxypyridine).
2-Phenoxypyridine (cas: 4783-68-0) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ璺痬ol閳? in pyridine vs. 150 kJ璺痬ol閳? in benzene). One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Application In Synthesis of 2-Phenoxypyridine