Construction of functionalized indans by thallium(III) promoted ring contraction of 3-alkenols
作者:Helena M.C Ferraz、Luiz F Silva
DOI:10.1016/s0040-4020(01)01021-3
日期:2001.12
Reformatsky reaction with bromo-esters (ethyl 2-bromopropionate, ethyl bromoacetate or ethyl 2-bromobutyrate), followed by dehydration of the β-hydroxy-ester formed. Reduction of the ester moiety led to homoallylic alcohols bearing an endocyclic double bond. The oxidative rearrangement of these 3-alkenols was performed by thallium trinitrate (TTN) in a 2:1 mixture of AcOH/H2O, leading to the ring contraction
开发了一种有效的四步方案,用于功能化茚满的构建。通过与溴酸酯(2-溴丙酸乙酯,溴乙酸乙酯或2-溴丁酸乙酯)的Reformatsky反应,将1-Tetralones转化为不饱和酯,然后将所形成的β-羟基酯脱水。酯部分的还原导致带有内环双键的均烯丙基醇。这些3-烯醇的氧化重排是通过三硝酸th(TTN)在AcOH / H 2 O的2:1混合物中进行的,导致环收缩产物的产率适中至非常好。研究了该序列的十四个例子。还研究了用TTN氧化由2-四氢萘酮制备的3-链烯醇。对于这些底物,未观察到环收缩反应。