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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Oxidation of the perchlorotriphenylmethyl radical to the carbocation, and its unique abrupt reversion
Manuel Ballester1, Carlos Miravitlles, Elies Molins
1Institut de Ciència de Materials de Barcelona, C.S.I.C., Campus Universitari de Bellaterra, 08193 Cerdanyola, Spain. elies.molins@icmab.es
Abstract:
A solution of AlCl(3) in CH(2)Cl(2) reacts slowly, at room temperature, with perchlorotriphenylmethyl radical (PTM(*)), an inert carbon free radical, to give perchlorotriphenylmethyl cation (PTM(+)) quantitatively. However, by gradual addition of CH(2)Cl(2) into the resulting solution a point is reached where the PTM(+) reverts to PTM(*) instantaneously and quantitatively. A mechanism for this exceptional phenomenon is suggested. Some PTM(+) reactions, namely hydrolysis yielding quinonoid species and single-electron transfers with hydride ion donors, are reported and discussed.
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