Premium
Mécanisme de solvolyse des cis ‐ et trans ‐( p ‐toluènesulfonates) d'aryl‐2‐cyclopentyle I. Etude de la première étape de la solvolyse: effets isotopiques de l' atone de deutérium en position 2, effets de sel basique et effet spécial de sel
Author(s) -
Ronco G.,
Petit J.P.,
Guyon R.,
Villa P.
Publication year - 1988
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19880710319
Subject(s) - chemistry , solvolysis , kinetic isotope effect , solvent , aryl , medicinal chemistry , salt (chemistry) , deuterium , stereochemistry , hydrolysis , organic chemistry , physics , alkyl , quantum mechanics
Solvolysis Mechanism of cis ‐ and trans ‐2‐Arylcylopentyl p ‐Toluenesulfonates. The Step: 1‐Deuterium Isotope Effects, Basic Salt Effects, and Special Salt Effect We have studied the first step of the solvolysis of cis and trans ‐2‐arylcyclopentyl p ‐toluenesulfonates in HCOOH, AcOH, and EtOh. All substrates show a high kinetic 1‐deuterium isotope effect ( k H / k D(1) >1.15). This fact indicates that first step leads to classical intimate ion‐pair Which dissociates to a solvet‐separated ion‐pair, without participation either of solvent, the 2‐aryl group, or a H‐atom at C(2). The slight influence of added basic ions on reaction rate allows us to exclude any direct solvent attack on the covalent substrate even in the most favorable case, i.e. ethanolysis of 2‐( p ‐nitrophenyl)cylopentyl‐ p ‐toluenesulfonates. Furthermore, solvent‐separated ion pair formation is indicated by the special salt effect induced by LiClO 4 .