Author:
,Konovalova S.A.,Burmistrov K.S.,Avdeenko A.P.,Pirozhenko V.V.,Toropin M.V.
Abstract
There are two following processes in the solutions of N-carbamoyl-1,4-benzoquinone monoimines: Z,E-isomerization with respect to the C=N bond and hindered rotation around the –NH–C(O)– bond, which can be registered by 1H NMR spectroscopy. The experimental values of the activation energy of these processes (G298) were determined as 67.21 and 62.05 kJ/mol, respectively. Z,E-Isomerization with respect to the C=N bond was found to run under the inversion mechanism. The theoretical values of the barriers of 3,5-dimethyl- and 2,6-dimethyl-N-carbamoyl-1,4-benzoquinone monoimines were calculated by quantum chemical calculations, they agreed well with experimental data.
Publisher
SHEI Ukrainian State University of Chemical Technology
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