1,2-二甲基-3-吲哚甲叉(异丙叉)丁二酸酐(1)和1,2-二甲基-3-吲哚乙叉(异丙叉)丁二酸酐(2)的晶体结构

Crystal Structures of 1,2-Dimethyl-3-Indolmethyl-Idene Succinic Fulgide Anhydride and 1,2-Dimethyl-3-Indolylethylidene Succinic Fulgide Anhydride

The crystal structures of 1,2-dimethyl-3-indolylmethylidene succinic fulgide anhydride (1) and 1,2-dimethyl-3-indolylethylidene succinic fulgide anhydride(2) were determined by singe crystal X-ray diffraction analysis. The crystal data are C_(18)H_(17)NO_3(1), orthogonal space group Pbca, with a=1.0084(3) nm, b=1.3966(4) nm, c=2.0945(6) nm, V=2.9498(15) nm, Z=8; C_(19)H_(19)NO_3 (2), orthogonal space group Pbca, with a=0.7988(3) nm, b=2.5782(10) nm, c=1.5664(5) nm, V=3.2259(22) nm, Z=8. R values are 0. 047 for (1) and 0.059 for (2) respectively.The photochemical properties of (1) and (2) were reported. Compound (1) is nonphotochromic, compound (2) changed from pale yellow to blue or green on irradiation at 365 nm or on exposure to indoor UV light either in crystal state or in solution (liquid or rigid plastic matrix).The differences in photochromic properties of compound (1) and (2) were discussed.