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。
through a thallium(III)-mediated ring contraction reaction of 1,2-dihydronaphthalene derivatives bearing suitably positioned primary and secondary hydroxyl groups are disclosed. The relative configuration of 3-(2,3-dihydro-1 1H-inden-3-yl)-2-methyl-3-oxopropyl 4-bromobenzoate was assigned by X-ray crystal structure analysis, allowing additional insights into the mechanism of the thallium(III)-promoted
公开了通过铊(III)介导的带有适当定位的伯羟基和仲羟基的1,2-二氢萘衍生物的环收缩反应合成茚满的几个方面。通过 X 射线晶体结构分析确定了 3-(2,3-dihydro-1 1H-inden-3-yl)-2-methyl-3-oxopropyl 4-bromobenzoate 的相对构型,从而进一步深入了解铊(III)促进高烯丙醇的氧化重排。使用过量的三硝酸铊 (TTN),带有吸电子基团溴的伯高烯丙醇的反应以 52-55% 的产率产生茚满。此外,仲高烯丙醇的铊(III)介导的氧化重排以非对映选择性的方式产生具有多达三个立体中心的茚满。
An efficient entry into butenolides: Synthesis of (±) mintlactone
作者:Subhash P. Chavan、P.K. Zubaidha、Nagaraj R. Ayyangar
DOI:10.1016/s0040-4039(00)61325-4
日期:1992.8
Osmylation of beta,gamma-unsaturated esters and acid catalysed cyclisation of the resultant diols generate butenolides in high yields.
An expeditious synthesis of hexahydrobenzo[f]isochromenes and of hexahydrobenzo[f]isoquinoline via iodine-catalyzed Prins and aza-Prins cyclization
作者:Luiz F. Silva、Samir A. Quintiliano
DOI:10.1016/j.tetlet.2009.02.202
日期:2009.5
Homoallylic alcohols (primary, secondary, or tertiary containing an endocyclic or an exocyclic double bond) react with equimolar amounts of aldehydes (aliphatic or aromatic) and ketones (aliphatic) in the presence of 5 mol % of iodine. This Prins cyclization was used in the preparation of hexahydrobenzo[f]isochromenes and of a 4-hydroxy-tetrahydropyran, in 54-81% yield. The procedure is also efficient for an aza-Prins cyclization of a homoallylic sulfonamide and benzaldehyde, producing a hexahydrobenzo[f]isoquinoline. (C) 2009 Elsevier Ltd. All rights reserved.
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。
Novel oxidative conversion of β,γ-unsaturated acids into butenolides: synthesis of heritonin and heritol
作者:Subhash P. Chavan、P. K. Zubaidha、Chitra A. Govande、Y. Tripura Subba Rao
DOI:10.1039/c39940001101
日期:——
A novel strategy of converting β,γ-unsaturated esters to butenolides involving oxidative cyclisation with ceric ammonium nitrate at room temperature is described.