Аннотация:A novel spirooxazine bearing sulfobutyl substituent on the indoline part of the molecule has
been synthesized and its photochromic properties and complex formation with metal ions
have been studied. Under UV light irradiation of colorless acetonitrile solution of
spirooxazine the open merocyanine form having an absorption band in visible region of the
spectrum with max=625 nm is generated. Thermal back reaction of merocyanine form to
spirooxazine with the rate constant 1.10 s-1 at 298 K has been observed. Interaction of
spirooxazine with Mg2+, Ca2+, Cd2+, Zn2+ or Pb2+ ions in the dark leads to the formation of
complexes of merocyanine form demonstrating a visible absorption band shifted from 20 to 8
nm relative to the uncomplexed merocyanine form. The activation energy of metal-induced
coloration process in the dark is in the range of 84-88 kJ mol-1 and does not depend on the
nature of the metal ions. This suggests that the process of thermal ring opening of the spiro
form is the rate limiting step of complex formation. The degree of conversion of spirooxazine
to complexed merocyanine form strongly depends on metal ions nature and irradiation
wavelength.
