已经表明,衍生自1,8-双(二甲基氨基)萘的2(7)-羰基衍生物的偶氮甲碱,和肟可以进行酸催化的杂环化作用,从而导致1-NMe 2基团的亲核取代。据信该方法与底物的质子海绵性质直接相关,其中作为不良离去基团的1-NMe 2通过形成螯合的质子化形式而被初步活化。已经以中等至高产率制备了许多难以接近的苯并[ g ]吲唑,苯并[ g ]喹唑啉,萘[2,1- d ]异恶唑和8-二甲基氨基-1-萘酚的衍生物。
1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation
作者:A S Antonov、A F Pozharskii、P M Tolstoy、A Filarowski、O V Khoroshilova
DOI:10.3762/bjoc.14.273
日期:——
neutral imines can be stabilised by an intramolecular C=N-H···OMe hydrogen bond with a neighbouring methoxy group. Electron-donating OMe groups dramatically increase the basicity of the imino nitrogen, forcing the latter to abstract a proton from the protonsponge moiety in monoprotonated forms. The participation of the out-inverted and protonated 1-NMe2 group in the Me2N-H···NH=C hydrogen bond is experimentally