Transformations of Acylation Products of Functionally 4-Substituted 2-Alkyl(aryl)-5-hydrazino-1,3-oxazoles into 1,3,4-Oxadiazole Derivatives
作者:A. V. Golovchenko、S. G. Pil’o、V. S. Brovarets、A. N. Chernega、B. S. Drach
DOI:10.1007/s11176-005-0244-8
日期:2005.3
Acylation products of 2-aryl-5-hydrazino-4-X-1,3-oxazoles [X = C(O)OAlk, P(O)(OAlk)2], when heated in acetic acid or ethanol, undergo recyclization and transform into the derivatives of 1,3,4-oxadiazol-2-ylglycine or its phosphonyl analog. A similar rearrangement also occurs in the reactions of 2-alkyl(aryl)-5-hydrazino-1,3-oxazole-4-carbonitriles with carboxylic acid chlorides in pyridine, but it is accompanied by additional cyclization involving the amide residue and nitrile group, yielding 2-(5-amino-1,3-oxazol-4-yl)-1,3,4-oxadiazole derivatives.
2-芳基-5-肼基-4-X-1,3-噁唑的酰化产物 [X = C(O)OAlk, P(O)(OAlk)2] 在加热于醋酸或乙醇时,发生重环化,转化为 1,3,4-噁二唑-2-基甘氨酸或其磷酸酯类似物的衍生物。在与吡啶中的羧酸氯化物反应时,2-烷基(芳基)-5-肼基-1,3-噁唑-4-腈也发生类似的重排,但伴随有额外的环化,涉及酰胺残基和腈基,生成 2-(5-氨基-1,3-噁唑-4-基)-1,3,4-噁二唑衍生物。