41002-34-0Relevant articles and documents
Reduction electrochimique des sels d'aryldiazonium en milieu aqueux: II. Effet de substituants sur la stabilisation du radical libre intermediaire de reduction et sur le rendement de la synthese d'arylhydrazines primaires
Hamet-Elfakir, Claire,Caullet, ClAude
, p. 687 - 692 (2007/10/02)
The polarographic behaviour of a series of aromatic diazonium salts , BF4- in aqueous media is reported and discussed.The half-wave potentials corresponding to the first reduction step have been correlated to Hammett substituent constant ? and are defined by the equation : E=0.14?-0.015+/-0.01 V vs SCE.Substituent effects on the yield of electrochemical synthesis on a mercury pool of by electrochemical reduction of aryldiazoniums salts 10E-3 mol.l-1 at 0 1,1 V vs.SCE are also investigated at low temperature.The best yield (70percent) are obtained with the electron donating substituents on the phenyl ring.Unfortunately, large scale electrolytic reduction of aromatic diazoniums 10E-2 mol.l-1 at -1,1 V vs SCE results in the formation of primary hydrazines in poor yields.On such a large scale, it no longer seems possible to minimize the competitive chemical side reactions.