Phthalazine → HCID 178518941, compound
Reaction equation
C1C2C(=CC=CC=2)C=[N:3][N:2]=1.[Br:11][C:12]1[CH:13]=[C:14]2[C:19](=O)[O:18][C:16](=[O:17])[C:15]2=[CH:21][CH:22]=1.NN>C(O)(C)C>[Br:11][C:12]1[CH:13]=[C:14]2[C:15](=[CH:21][CH:22]=1)[C:16]([OH:17])=[N:3][N:2]=[C:19]2[OH:18]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
The synthesis of phthalazine derivatives of general formulas 25-26 may be achieved as outlined in Scheme III. In general, a mixture of 4-bromophthalic anhydride and hydrazine may be refluxed in a suitable solvent, e.g., isopropyl alcohol, to provide 6-bromo-phthalazine-1,4-diol 21 in almost quantitative yield. Compound 21 may then be treated with phosphorus oxychloride to form 1,4-dichloro-6-bromo phthalazine 22. Treatment of compound 22 with a suitable nucleophile (where, for example, Y is NR1R2 or NaOR) affords two isomers of general formulas 23 and 24. Displacement of the bromine atom with a suitable amino or alcohol derivative A-B—X (where, for example, A is alkyl, aryl, arylalkyl, arylheteroalkyl, B is absent, CO, and X is OH, NH2), using a suitable Pd complex derivative in the presence of a base like sodium tert-butoxide in a suitable solvent, affords the desired 6-amino or 6-alkoxy phthalazine derivatives of general formula 25-26.
Sources & evidence
- ORD record
- ord-b7e4a69c091e442d8999a056af14b740
- Source dataset
- uspto-grants-2013_01
- Patent number
- US08349836B2
Reaction notes
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