SYNTHESIS AND PHOTOCHROMIC PROPERTIES OF INDOLINOSPIROCHROMENES WITH ELECTRON-DONOR SUBSTITUENTS IN THE INDOLINE PART OF THE MOLECULE

Article abstract of DOI:10.1007/BF00513436

1,3,3-Trimethylspiro(indoline-2,2'-<2H>chromenes) with CH3 and CH3O groups in the 4-7 positions and NO2 and CH3O groups in the 6' and 8' positions were obtained by the reaction of 4,6-, 4,7-, 5,6-, and 6,7-dimethoxy- and 4-methyl-7-methoxy-2-methyleneindoles and 1,3,3,4,5,6,7-heptamethyl-2-methyleneindolines with 3- and 5-nitrosalicylaldehydes and their derivatives.Most of the compounds have photochromic properties.The introduction of electron-donor groups into the indoline fragment of the spirochromene molecules changes the rate of the dark reaction within the limits of one order of magnitude and has a small effect on the position of the long-wave absorption band of the photomerocyanine.