in CH2Cl2 followed by the addition of an alcohol in the presence of manganese dioxide under ultrasonic irradiation constitutes a stereoselective one-pot procedure for the preparation of Z-configured α–bromo-α,β-unsaturatedesters in good to excellent yield.
Site-specific preparation of 4-substituted-6-fluoro(carboalkoxyl)benzo[b]furans and benzo[b]thiophenes via base-catalyzed cyclization of enyne derivatives
作者:Yi Wang、Donald J. Burton
DOI:10.1016/j.jfluchem.2007.05.019
日期:2007.9
synthesis of 4-substituted-6-fluoro(carboalkoxyl)benzo[b]furans and benzo[b]thiophenes is described. The reactions of heterocyclic aromatic aldehydes with a Wittig reagent, followed by Sonogashira reaction with terminal alkynes, and subsequent base-catalyzedcyclization site-specifically provide 4-substituted-6-fluoro(carboalkoxyl)benzo[b]furans and benzo[b]thiophenes in good yields.
描述了4-取代的6-氟(羰基烷氧基)苯并[ b ]呋喃和苯并[ b ]噻吩的位点特异性合成。杂环芳族醛与Wittig试剂反应,然后与末端炔烃进行Sonogashira反应,然后进行碱催化的环化位点,可特异性地提供4-取代的6-氟(羰基烷氧基)苯并[ b ]呋喃和苯并[ b ]噻吩丰产。
The reaction of substituted ethyl α-bromocinnamates with tetrabutyl ammonium fluoride
作者:Yan Liang、Ying Peng Zhang、Wei Yu
DOI:10.1016/j.cclet.2012.05.015
日期:2012.7
-bromocinnamates with tetrabutyl ammonium fluoride (TBAF) was influenced largely by the position of the substituent at the phenylring. While the substrates without an ortho substituent at the phenylring were transformed to the corresponding β -fluoro ethyl cinnamates under the reaction conditions, the presence of an ortho substituent only resulted in the formation of ethyl 3-phenylpropiolate derivatives
Preparation of α-Bromoacrylates: One-Pot Procedure for the Synthesis of Conjugated Acetylenic Carboxylates from Aldehydes with Ph<sub>3</sub>P/Br<sub>3</sub>CCO<sub>2</sub>Et
作者:Doo Jang、Joong-Gon Kim、Dong Kang
DOI:10.1055/s-2008-1032070
日期:2008.2
established the optimal conditions for the Wittig reaction for synthesizing α-bromoacrylates with a high selectivity, and developed a simple and efficient one-pot procedure for preparing various conjugated acetylenic carboxylates in moderate to high yields.