Samarium Diiodide Mediated Ketyl-Aryl Coupling Reactions - Influence of Substituents and Trapping Experiments
作者:Ulrike K. Wefelscheid、Mathias Berndt、Hans-Ulrich Reißig
DOI:10.1002/ejoc.200800293
日期:2008.7
derivatives as single diastereoisomers in most cases. The position of the substituents was also of crucial influence on the outcome; in several cases ipso-substitution leading to the formation of spiro compounds was observed. Electron-donating substituents at the aromatic moiety are less favourable for the ketyl–aryl couplings. They apparently impede the second electron transfer that is involved in this multi-step
Heck Reaction of Aryl Bromides with Pent-4-en-2-ol, 2-Phenylpent-4-en-2-ol, or Hept-6-en-3-ol Catalysed by a Palladium-Tetraphosphine Complex
作者:Henri Doucet、Maurice Santelli、Florian Berthiol
DOI:10.1055/s-2005-918427
日期:——
depends on the substituents on the aryl bromide and on the base. Sterically congested and electron-rich aryl bromides gave selectively the linear ketones by migration of the double bond. With electron-poor aryl bromides, the formation of large amounts of (E)-arylalk-1-enol derivatives or side products was observed in some cases. Similar reactions rates were observed with electron-poor and electron-rich