Phosphorus oxychloride → 1-Chlorophthalazine
Reaction equation
[CH:1]1[CH:2]=[CH:3][C:4]2[C:5](=[CH:7][N:8]=[N:9][C:10]=2O)[CH:6]=1.P(Cl)(Cl)([Cl:14])=O>>[Cl:14][C:10]1[C:4]2[C:5](=[CH:6][CH:1]=[CH:2][CH:3]=2)[CH:7]=[N:8][N:9]=1Participants
Procedure
The process according to one embodiment of this invention comprises the steps of: a) reacting phthalazinone with an approximately equimolar equivalent of phosphorous oxychloride at a specific temperature to produce a 1-chlorophthalazine salt; b) isolating the 1-chlorophthalazine salt formed in step (a) by precipitating the 1-chlorophthalazine salt by adding a mineral acid in the presence of solvent and filtering and drying the solid 1-chlorophthalazine salt; c) reacting the isolated and dried 1-chlorophthalazine salt with hydrazine hydrate without any organic solvent and precipitating the hydralazine base by adding a solvent; d) purifying the hydralazine base in a non-aqueous medium; e) converting the purified hydralazine base to hydralazine hydrochloride in a non-aqueous medium and isolating therein; and f) purifying the isolated hydralazine hydrochloride in aqueous medium
Sources & evidence
- ORD record
- ord-5f326cae4e5d401cb33310d6e626cde6
- Source dataset
- uspto-grants-2010_10
- Patent number
- US07807830B2
Reaction notes
Loading…