Stereochemistry of nucleophilic substitution reactions depending upon substituent: evidence for electrostatic stabilization of pseudoaxial conformers of oxocarbenium …

…, JAC Romero, SA Tabacco, KA Woerpel

Index: Ayala, Leticia; Lucero, Claudia G.; Antoinette, Jan; Romero; Tabacco, Sarah A.; Woerpel Journal of the American Chemical Society, 2003 , vol. 125, # 50 p. 15521 - 15528

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Citation Number: 176

Abstract

Lewis acid-mediated nucleophilic substitution reactions of substituted tetrahydropyran acetates reveal that the conformational preferences of six-membered-ring cations depend significantly upon the electronic nature of the substituent. Nucleophilic substitutions of C-3 and C-4 alkyl-substituted tetrahydropyran acetates proceeded via pseudoequatorially substituted oxocarbenium ions, as would be expected by consideration of steric effects. ...

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