Intermediates for the preparation of pyrazoloazole photographic couplers, processes of making and using them
US5565572A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Oct 15, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D487/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
There are described intermediates for the preparation of known pyrazoloazole photographic magenta dye forming couplers and processes for making and using these intermediates. The intermediates are low molecular weight compounds represented by the structure: ##STR1## wherein: R, X, R.sup.1 and Y are defined herein. The process for making these intermediates involves diazotizing a 5-amino-1H-pyrazole to produce a 5-diazo-1H-pyrazole, then condensing the diazotized product with an active methine or methylene compound having a pKa of 14 or less to produce a substituted hydrazone and then subjecting the hydrazone to cyclization and reduction, in either order.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.