A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences, 1 Favorsky Str., 664033 Irkutsk, Russia.
Molecules. 2021 Nov 11;26(22):6824. doi: 10.3390/molecules26226824.
Publications covering a new easy metal-free functionalization of pyridinoids (pyridines, quinolines, isoquinolines, acridine) under the action of the system of electron-deficient acetylenes (acetylenecarboxylic acid esters, acylacetylenes)/-nucleophiles (phosphine chalcogenides, -phosphonates) are reviewed. Special attention is focused on a S reaction of the regioselective cross-coupling of pyridines with secondary phosphine chalcogenides triggered by acylacetylenes to give 4-chalcogenophosphorylpyridines. In these processes, acetylenes act as three-modal adjuvants (i) activating the pyridine ring towards -nucleophiles, (ii) deprotonating the P-H bond and (iii) facilitating the nucleophilic addition of the -centered anion to a heterocyclic moiety followed by the release of the selectively reduced acetylenes (-alkenes).
本文综述了在缺电子炔烃（乙酰羧酸酯、酰基炔烃）/亲核试剂（膦杂环戊二烯、膦酸酯）体系作用下，吡啶类化合物（吡啶、喹啉、异喹啉、吖啶）的新型简便的金属自由功能化反应。特别关注的是酰基炔烃引发的吡啶与二级膦杂环戊二烯的区域选择性交叉偶联的 S 反应，生成 4-杂原子膦酰基吡啶。在这些过程中，炔烃作为三模态助剂（i）活化吡啶环与亲核试剂反应，（ii）去质子化 P-H 键，（iii）促进 -中心阴离子对杂环片段的亲核加成，随后选择性还原的炔烃（-烯烃）释放。
