Synergistic dual activation catalysis by palladium nanoparticles for epoxide ring opening with phenols
作者:Kapileswar Seth、Sudipta Raha Roy、Bhavin V. Pipaliya、Asit K. Chakraborti
DOI:10.1039/c3cc42507j
日期:——
Synergistic dual activation catalysis has been devised for epoxide phenolysis wherein palladium nanoparticles induce electrophilic activation via coordination with the epoxide oxygen followed by nucleophilic activation through anion-pi interaction with the aromatic ring of the phenol, and water (reaction medium) also renders assistance through 'epoxide-phenol' dual activation.
Chiral Epoxides via Borane Reduction of 2-Haloketones Catalyzed by Spiroborate Ester: Application to the Synthesis of Optically Pure 1,2-Hydroxy Ethers and 1,2-Azido Alcohols
作者:Kun Huang、Haiyang Wang、Viatcheslav Stepanenko、Melvin De Jesús、Carilyn Torruellas、Wildeliz Correa、Margarita Ortiz-Marciales
DOI:10.1021/jo102294j
日期:2011.3.18
with 10% spiroaminoborate ester 1 as catalyst is described. By a simple basic workup of 2-halohydrins, optically active epoxides are obtained in high yield and with excellent enantiopurity (up to 99% ee). Ring-opening of oxiranes with phenoxides or sodium azide is investigated under different reaction conditions affording nonracemic 1,2-hydroxy ethers and 1,2-azido alcohols with excellent enantioselectivity
A catalyst-free regio- and stereoselective ring-opening of epoxides with phenoxides has been carried out efficiently using polyethyleneglycol as the reaction medium to form the corresponding β-aryloxyalcohols in high yields at room temperature.
Bi(OTf)<sub>3</sub>-catalyzed Regioselective Ring Opening of Epoxides with Phenols: Facile Synthesis of 1,3-Diaryloxy-2-propanols
作者:Ahmed Kamal、Syed Kaleem Ahmed、Mahendra Sandbhor、Mohammed Naseer Ahmed Khan、Mohammed Arifuddin
DOI:10.1246/cl.2005.1142
日期:2005.8
Substituted aryl oxiranes undergo the facileringopening with phenols in the presence of catalytic amount of bismuth(III) triflate to afford 1,3-diaryloxy-2-propanols in excellent yields under mild conditions. Bismuth(lll) triflate is relatively nontoxic, easy to handle and inexpensive, which makes this procedure particularly attractive for large scale synthesis.
Highly Regioselective Ring Opening of Epoxides with Polymer Supported Phenoxide and Naphthoxide Anions
作者:B. Tamami、N. Iranpoor、R. Rezaei
DOI:10.1081/scc-200026220
日期:2004.1
Abstract Amberlite IRA‐400 supported phenoxide and naphthoxide anions are easily prepared. These polymer supported reagents that are highly air stable are used for the regioselective ringopening reactions of different epoxides to give aryl ether alcohols in high yields under mild reaction conditions.