Four new crown squarylium cyonine dye(2a~2d)were synthesized by condensation of squaric acid with crown benzothiazolium halide(1a~1d) in the presence of pyridine.Their structures have been confired by IR,UV Vis, 1H ...Four new crown squarylium cyonine dye(2a~2d)were synthesized by condensation of squaric acid with crown benzothiazolium halide(1a~1d) in the presence of pyridine.Their structures have been confired by IR,UV Vis, 1H NMR,MS and elemental analyses.It was found that these crown squarylium cyanine dye (2a~2d) were in reserse photochromie equilibriam.展开更多
文摘Four new crown squarylium cyonine dye(2a~2d)were synthesized by condensation of squaric acid with crown benzothiazolium halide(1a~1d) in the presence of pyridine.Their structures have been confired by IR,UV Vis, 1H NMR,MS and elemental analyses.It was found that these crown squarylium cyanine dye (2a~2d) were in reserse photochromie equilibriam.