Etude de composés d'addition d'acides de Lewis, XXXIV [1] Composés d'addition de benzoquinone‐1, 4 avec TiCl₄

Abstract

V 71)S u m m a r y . The adduct 1,4-benzoquinone.TiCl~ has been prepared in CH,Cl, solution at about -6OD. Its I K . spectrum has been recorded a t the same temperature. The experimental study of the vibrational frequencies has been completed by the calculation of the fundamental vibrations in the molecular plane, using Wilson's FG method, with slightly simplified models of 1,4-benzoquinone. TiC1, (13 masses) and 1,4-bcnzoquinone.2TiCI, (14 masses) ; analysis by use of internal and symmetry coordinates. .4n assignnient of most of thc obscrved bands is proposed and the conclusion is rcached that the complex, when solid, is (1,4-benzoquinone.TiC1,),.The force constants F(C=O) are 9,85 . lo5 dync/cm for the quinone and 8,8 . lo5 dyne/cm for the disturbed carbonyl bond of the polymerizcd complex in the model proposed.At ordinary temperature in benzene solution of the components the adduct 1,4-benzoquinone. TiCl,.benzene precipitated; with thc hclp of the models, thc fundamental vibrations of its IR. spcctruni have been assigncd.