Properties of triarylimidazolyl radicals and their dimers

Abstract

Biophysics, for the use of laboratory facilities and for salary and computer support. Thanks are also due to the Mental Health Board of Alabama for partial financial assistance.

Photocrystallisation of the 2C–2′C dimer of a triphenylimidazolyl radical

“…330 nm. Compared to the unsubstituted TPIR, 27 there is a bathochromic shi of ca. 170 nm (4300 cm À1 ) in the low-energy band, demonstrating the colour tuning of these photochromic materials (from violet to green in this case).…”

Electrochemical topological transformation of polysiloxanes

“…2a ). Both 1 and the product after chemical oxidation ( 2 ) are known compounds 21 and thus allow straightforward characterization. Screening revealed successful oxidation in the presence of ( n Bu) 4 NClO 4 as a support electrolyte in dichloromethane (DCM) or in a mixture of DCM and methanol (MeOH).…”

The formation of peroxide degradation products of photochromic triphenylimidazolyl radical-dimers

“…To explore further the generality of the observed degradation, five simple TPIR dimers, previously reported by Cescon and co-workers, 28 namely the parent unsubstituted radical dimer, the o-chloro substituted dimer that is used as a polymerisation initiator, the p-chloro isomer, the o-methyl derivative and the mesityl derivative, were investigated for peroxide formation. The chosen compounds span an order of magnitude of dimerisation rates from the relatively rapid o-chloro, intermediate rate o-methyl, to the slower p-chloro.…”

“…The chosen compounds span an order of magnitude of dimerisation rates from the relatively rapid o-chloro, intermediate rate o-methyl, to the slower p-chloro. 28 Thus, using a similar method to that described for the 4-tert-butyl example above, a sample of each was irradiated (365 nm) under an oxygen atmosphere and the formation of by-products was followed by ESI + MS. In each case peroxide formation was observed (see ESI † for accurate mass data and spectra for each derivative).…”