Regioselectivity of electrophilic attack on 4-methyl-1-thioxo-1,2,4,5-tetrahydro[1,2,4]triazolo[4,3-a]quinazolin-5-one. Part 1: Reactions at the sulfur atom
Regioselectivity of electrophilic attack on 4-methyl-1-thioxo-1,2,4,5-tetrahydro[1,2,4]triazolo[4,3-a]quinazolin-5-one. Part 1: Reactions at the sulfur atom
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DOI：
10.3390/60600557
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发表时间：
2001-06-01
期刊：
影响因子：
4.6
通讯作者：
Pazdera, P
中科院分区：
文献类型：
--
作者：
Fathalla, W;Cajan, M;Pazdera, P
研究了模型化合物4-甲基-1-硫代-1,2,4,5-四氢[1,2,4]三唑并[4,3-a]喹唑啉-5-酮(3)对不同亲电子试剂的区域选择性。化合物3与烷基卤化物和芳基卤化物反应得到相应的S-取代衍生物。模型硫代酰胺与酰卤的反应通过形成动力学控制的S-酰基衍生物进行，然后进行酰基转移反应，得到N-2-酰基衍生物作为热力学控制的产物。理论 DFT 计算研究支持了对这些结果的解释。合成的化合物通过 FTIR、H-1-NMR、C-13-NMR 和质谱进行表征。
The regioselectivity of the model compound 4-methyl-1-thioxo-1,2,4,5-tetrahydro[1,2,4]triazolo[4,3-a]quinazolin-5-one (3) towards different electrophiles was studied. Compound 3 reacts with alkyl and aryl halides to give the corresponding S-substituted derivatives. The reaction of the model thioamide with acyl halides proceeds by the formation of kinetically controlled S-acyl derivatives followed by a transacylation reaction to give the N-2-acyl derivatives as thermodynamically controlled products. Theoretical DFT computational studies supported the explanation of these results. The synthesized compounds were characterized by FTIR, H-1-NMR, C-13-NMR, and mass spectroscopy.