The correlation of Lewis acidities of silyl triflates with reaction rates of catalyzed diels-alder reactions

European Journal of Organic Chemistry

Volumn , Issue 35, 2011, Pages 7071-7075

  Hilt, Gerhard ^a   Nödling, Alexander ^a  

^a PHILIPPS UNIVERSITY MARBURG   (Germany)

Author keywords

Cycloaddition; Kinetics; Lewis acids; NMR spectroscopy

Indexed keywords

EID: 82455175751     PISSN: 1434193X     EISSN: 10990690     Source Type: Journal    
DOI: 10.1002/ejoc.201101307     Document Type: Article

References (14)

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11. 3SiOTf- catalyzed Diels-Alder reaction resulted in no conversion after 24 h at room temperature. This could indicate that protons are the catalytically active species. However, investigations by others have shown that 2,6-di-tert- butylpyridine is able to interact with sterically hindered Lewis acids such as triphenylcarbenium ions and trialkylsilyl cations, which would also explain the absence of catalytic activity (see:, M. J. Therien, C.-L. Ni, F. C. Anson, J. G. Osteryoung, W. C. Trogler, J. Am. Chem. Soc. 1986, 108, 4037.
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