Synthesis of ([1,2,4]triazolo[4,3-<i>a</i>]pyridin-3-ylmethyl)phosphonates and their benzo derivatives via 5-<i>exo</i>-<i>dig</i> cyclization
作者:Aleksandr S Krylov、Artem A Petrosian、Julia L Piterskaya、Nataly I Svintsitskaya、Albina V Dogadina
DOI:10.3762/bjoc.15.159
日期:——
A series of novel 3-methylphosphonylated [1,2,4]triazolo[4,3-a]pyridines was accessed through a 5-exo-dig-type cyclization of chloroethynylphosphonates and commercially available N-unsubstituted 2-hydrazinylpyridines. In addition, 3-methylphosphonylated [1,2,4]triazolo[4,3-a]quinolines and 1-methylphosphonylated [1,2,4]triazolo[3,4-a]isoquinolines were synthesized in a similar manner. The presence
一系列新的3- methylphosphonylated [1,2,4]三唑并[4,3的一个〕吡啶物通过5-访问外型-挖chloroethynylphosphonates和市售的N-未取代的2- hydrazinylpyridines的型环化。另外,以类似的方式合成了3-甲基膦酰化的[1,2,4]三唑并[4,3- a ]喹啉和1-甲基膦酰化的[1,2,4]三唑并[3,4- a ]异喹啉。起始肼基吡啶中NO 2基团的存在引起Dimroth型重排,导致2-甲基膦酰化的[1,2,4]三唑并[1,5- a ]吡啶。