Über die Photochromie der Fulgide. IX Untersuchungen zur Photochemie des α-3,5-Dimethyoxyphenyl-δ-δ-dimethylfulgids

The Photochromism of Fulgides. IX. Investigations of the Photochemistry of α-3,5-Dimethoxyphenyl-δ,δ-dimethylfulgide The mechanism of photoisomerization of α-3,5-dimethoxyphenyl-δ, δ-dimethylfulgide was investigated by means of u.v./vis- and fluorescence spectroscopy. The quantum yields of E-Z isomerization and cyclisation were determined in various solvents and at different temperatures. Triplet sensitization of E-Z isomerization by several sensitizers has been found. The thermal dark reactions of the deep coloured species were reinvestigated.