Spiro indoline-pyranobenzoxazinones
US4831142A · kind A · utility
14Cited by
7References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1988 |
| Grant date | May 16, 1989 |
| Priority date | — |
| Expiry date | Sep 28, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D498/20
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Photochromic spiro-oxizine compounds are prepared by mixing in a substantially non-reactive organic solvent medium an alkylidene heterocyclic compound or halide salt thereof, e.g., an indoline, with a metal chelate of an ortho-hydroxynitrosoaromatic compound.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.