Process for preparing the spiropyrone compounds
US5693830A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1994 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Apr 8, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D495/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Spiropyrone compounds represented by the general formula ##STR1## wherein ##STR2## is a substituted or an unsubstituted aromatic hydrocarbon group or a substituted or an unsubstituted unsaturated heterocyclic group, and ##STR3## is a substituted or an unsubstituted 2-bicyclo3,3,1!9-nonenylidene group, that are starting materials of spiropyran compounds which change from a colorless state into a colored or a densely colored state upon irradiation with the light containing ultraviolet rays such as the sunlight or the light of a mercury lamp, the change being reversible, and a process for preparing the spiropyrone compounds. The process comprises reacting a compound represented by the general formula ##STR4## wherein ##STR5## is as defined above, with a compound of the general formula ##STR6## wherein ##STR7## is as defined above.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.