Reagent-controlled stereoselection in radical addition to α-methylenebutyrolactones
作者:Hirokazu Urabe、Katsushige Kobayashi、Fumie Sato
DOI:10.1039/c39950001043
日期:——
Some β- or γ-substituted α-methylenebutyrolactones are butylated with Bul and (Me3Si)3SiH to give cis-α,β- or -α,γ-disubstituted lactones in high selectivites, while the same reaction with Bu3SnH in the presence of bulky Lewis acid reverses the stereoselectivity to give a trans-disubstituted lactone as the major product.
A New Method for the Preparation of α-Methylene-γ-butyrolactones Using 3-Ethoxycarbonyl-3-(phenylsulfonyl)cyclobutanone
作者:Tooru Fujiwara、Koichi Morita、Takeshi Takeda
DOI:10.1246/bcsj.62.1524
日期:1989.5
The reaction of 3-ethoxycarbonyl-3-(phenylsulfonyl)cyclobutanone with Grignard reagent or aryllithium gave 1-(alkyl or aryl)-3-ethoxycarbonyl-3-(phenylsulfonyl)cyclobutanol which was treated with potassium hydride, reduced with LiBH4 in the presence of ZnCl2, and treated with p-TsOH or aluminum triisopropoxide successively to give α-methylene-γ-butyrolactone in good yield.
this article is a palladium(II)/copper(II)‐ or palladium(II)‐catalyzed intermolecular cyclization of acrylic acid with alkenes to produce α‐methylene‐γ‐butyrolactone derivatives using molecular oxygen as an environmentally benign oxidant. In this system, the carboxylato, especially trifluoroacetato, or trimethylacetato ligand, plays a quite important role to afford a high catalytic activity by suppressing
Synthesis of unsaturated butyrolactones by palladium catalyzed intramolecular carboalkoxylation of homoallylic chloroformates
作者:Françoise Henin、Jean-Pierre Pete
DOI:10.1016/s0040-4039(00)86228-0
日期:1983.1
We propose a new method for the preparation of α-methylene lactones involving the palladium (o) catalyzed cyclisation of homoallylic chloroformates .
我们提出了一种新的制备α-亚甲基内酯的方法,该方法涉及钯(o)催化均烯丙基氯甲酸酯的环化反应。
A New Approach for the Synthesis of α-Methylene-γ-Butyrolactones from α-Bromomethyl Acrylic Acids (or Esters)
作者:Jing-yao Zhou、Guo-di Lu、Shi-hui Wu
DOI:10.1080/00397919208019246
日期:1992.2
Abstract This paper reports that a new approach for the synthesis of α-methylene-γ-butyrolactones from the reaction of α-bromomethyl acrylic acid (or ester), powdered tin and carbonyl compounds in one pot with excellent to good yields.