Process for the production of phthalazineacetic acid ester derivatives and a novel intermediate
US4904782A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 29, 1988 |
| Grant date | Feb 27, 1990 |
| Priority date | — |
| Expiry date | Feb 29, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D237/32
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a process for the production of phthalazineacetic acid ester derivatives of the formula ##STR1## wherein R is (C.sub.1 -C.sub.4) alkyl which comprises reacting (Z)-3-oxo-1(3H)-isobenzofuranylideneacetic acid with hydrazine in the presence of a solvent; reacting the resulting mixture of the novel compound 1-hydrazino-1,2,3,4-tetrahydro-4-oxo-phthalazineacetic acid and 3,4-dihydro-4-oxo-phthalazineacetic acid with acid in the presence of a solvent; and reacting the resulting 3,4-dihydro-4-oxo-phthalazineacetic acid with acid in the presence of an alcohol. This invention also relates to the novel compound 1-hydrazino-1,2,3,4-tetrahydro-4-oxo-phthalazineacetic acid of the formula ##STR2## which is an intermediate formed in the process of this invention and which is useful for the production of phthalazineacetic acid ester derivatives of formula IV. The compounds of formula IV are useful for the preparation of certain heterocyclic oxophthalazinyl acetic acids and esters thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.