Nitrogen bridgehead compounds. Part<b>50</b>. Vilsmeier-haack acylation of 6,7,8,9-tetrahydro-4<i>H</i>-pyrido[1,2-<i>a</i>]pyrimidin-4-ones, Part 5
作者:Ágnes Horváth、István Hermecz、Benjamin Podányi、Zoltán Mészáros
DOI:10.1002/jhet.5570220302
日期:1985.5
using N,N-diphenylformamide or in a “one-pot” procedure with aniline and triethyl orthoformate. Ethanolysis of 9-N-methyl-N-phenylaminomethylene derivatives 15 and 19 afforded 9-ethoxy-methylene compounds 26 and 27 in the presence of hydrogen chloride. The structures of the 9-substituted 6-methyltetrahydropyridopyrimidin-4-ones 14-25 were elucidated by means of uv, 1H and 13C nmr spectroscopy. 9-Piperidinomethylene
将6-甲基-6,7,8,9-四氢-4 H-吡啶并[1,2 - a ]嘧啶-4-酮1-5与磷酰氯和不同酰胺的络合物进行Vilsmeier-Haack酰化反应。由N-甲酰基哌啶,N-甲基甲酰苯胺或N,N-二乙基苯甲酰胺原位形成的亚胺盐成功地完成了嘧啶嘧啶的9位酰化反应,但未成功由N,N-二乙基乙酰胺或N,N形成的亚胺盐成功-二乙基异丁酰胺。由甲酰苯胺(N)形成的亚胺盐-甲基吡咯烷酮或甲酰胺仅与在位置3上具有强电负性取代基(例如CN或CO 2 Et)的四氢吡啶并嘧啶酮反应。对于后者的衍生物,可以使用N,N-二苯基甲酰胺或在“苯胺和原甲酸三乙酯的“一锅法”操作。在氯化氢存在下,对9- N-甲基-N-苯基氨基亚甲基衍生物15和19进行乙解,得到9-乙氧基-亚甲基化合物26和27。9-取代的6-甲基四氢吡啶并嘧啶丁-4-酮的结构14-25通过紫外,1 H和13 C核磁共振波谱法进行了阐明。9 Piperidinomethylene