作者:Anna Kwiecień、Maciej Barys、Zbigniew Ciunik
DOI:10.3390/molecules190811160
日期:——
Under neutral conditions the reactions between 4-amino-1,2,4-triazole and cyano-substituted benzaldehyde derivatives yield stable hemiaminals. Addition of small amounts of acid catalyst promotes further step of dehydration resulting in formation of Schiff bases. Four new hemiaminals and the corresponding imines have been obtained. The molecular stability of the hemiaminal intermediates results from both the 1,2,4-triazole moiety and electron withdrawing substituents on the phenyl ring, so no further stabilisation by intramolecular interaction is required. Hemiaminal molecules possess stereogenic centres on carbon and nitrogen atoms. The chirality of these centres is strongly correlated with the conformation of the molecules due to heteroatom hyperconjugation effects.
在中性条件下,4-氨基-1,2,4-三唑和氰基取代的苯甲醛衍生物之间的反应会生成稳定的半氨基化合物。加入少量酸催化剂可促进进一步脱水,从而形成希夫碱。现已获得四种新的半氨基化合物和相应的亚胺。半二胺中间体的分子稳定性来自 1,2,4-三唑分子和苯基环上的退电子取代基,因此不需要通过分子内相互作用进一步稳定。半醛分子的碳原子和氮原子上都有立体中心。由于杂原子的超共轭效应,这些中心的手性与分子的构象密切相关。