Premium
Le mécanisme de la réduction polarographique des dérivés ditosyloxylés et son implication en électrochimie préparative
Author(s) -
Gerdil Raymond
Publication year - 1973
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.19730560606
Subject(s) - chemistry , vicinal , intramolecular force , yield (engineering) , stereochemistry , molecule , polarography , steric effects , medicinal chemistry , organic chemistry , materials science , metallurgy
The cleavage of a single SO 2 O bond occurs during the polarographic reduction of a tosyloxy group ( p CH 3 C 6 H 4 SO 2 O = TsO) in aprotic medium and intramolecular cyclisation may ensue when a second TsO group is present on the same molecule. The polarographic behaviour of aliphatic ditosyloxy derivatives is discussed on the assumption that oriented vicinal derivatives at the interface assume a conformation which resembles the geometry of the transition state for an intramolecular elimination with anchimeric assistance of one of the tosyloxy groups. This situation favours the electron transfer, whereas the same geometric requirements hinder the intramolecular interaction of the TsO groups of the oriented non‐vicinal derivatives. This interpretation agrees well with the fact that the large scale electrolysis of vicinal ditosyloxy derivatives give much higher yield of cyclic ethers than the higher homologues. It is also shown that intramolecular interaction between TsO groups can occur through an intervening double bond in a non‐vicinal derivative.