S. Aldoshin, L. Atovmyan, O. A. D’yachenko
Dec 1, 1981
Citations
0
Influential Citations
5
Citations
Journal
Bulletin of the Academy of Sciences of the USSR, Division of chemical science
Abstract
Conclusions1.X-ray structure analysis has been applied in an investigation of the molecular and crystal structure of the original 1,3,3-trimethyl-6′-nitro-8′-bromospiro(indolin-2,2′-[2H-1]-benzopyran) and the product of its photochemical conversion.2.It has been unambigously confirmed that when a light quantum is absorbed in the spiropyran molecule, the bond between the spiro-carbon and oxygen of the pyran part of the molecule is ruptured, with subsequent cis-trans isomerization of the vinyl group.3.The stability of the photoproduct is very much dependent on the magnitude of the contribution of the quinoid form to the structure of the phenolate fragment, on solvation of the phenolate oxygen atom, and on intermolecular and intramolecular hydrogen bonding.