A convenient CeCl3·7H2O/NaI-promoted synthesis of structurally novel and strained tricyclic β-lactams from hydrazines
作者:Lal Dhar S. Yadav、Vijai K. Rai
DOI:10.1016/j.tetlet.2008.07.068
日期:2008.9
derivatized tricyclic β-lactams has been developed. The synthesis involves CeCl3·7H2O/NaI catalyzed addition–condensation of mercaptoacetic acid and N-aroyl-N′-arylidenehydrazines followed by intramolecular cyclodehydration to afford bicyclic 5H-thiazolo[4,3-b][1,3,4]-oxadiazoles, which on treatment with acid chlorides in the presence of triethylamine furnish highly derivatized tricyclic 3H-azetidino[2
已经开发了用于结构新颖和应变的高度衍生化的三环β-内酰胺的方便的合成方案。合成涉及加入CeCl 3 ·7H 2 O /碘化钠催化的巯基乙酸和的加成缩合Ñ -aroyl- Ñ '-arylidenehydrazines随后分子内脱水环化,得到双环5 ħ -噻唑并[4,3- b ] [1,3, 4]-恶二唑类化合物,在三乙胺存在下用酰氯处理,可提供高度衍生的三环3 H-氮杂环丁烷[2,1- b ]-噻唑并[3,4- d] [1,3,4]-恶二唑-6-酮,产率80-93%。此过程很好地说明了Ce(III)催化一锅法形成C–C,C–N和C–S键的过程。