Maleic Anhydride → 4-[(6-chloro-1H-indazol-3-yl)amino]-4-oxo-2-butenoic acid

HRID 497582

Reaction equation

[C:1]1(=[O:7])[O:6][C:4](=[O:5])[CH:3]=[CH:2]1.[Cl:8][C:9]1[CH:17]=[C:16]2[C:12]([C:13]([NH2:18])=[N:14][NH:15]2)=[CH:11][CH:10]=1>C1(C)C(C)=CC=CC=1>[Cl:8][C:9]1[CH:17]=[C:16]2[C:12]([C:13]([NH:18][C:1](=[O:7])[CH:2]=[CH:3][C:4]([OH:6])=[O:5])=[N:14][NH:15]2)=[CH:11][CH:10]=1

Participants

Conditions

Temperature: 145 °C

Procedure

585 mg of preground maleic anhydride are added to 1 g of 6-chloro-1H-indazole-3-amine in 30 cm3 of ortho-xylene. The reaction medium is refluxed at 145° C. for ten minutes and then cooled in a water bath. The insoluble material is filtered off and washed successively with 2×25 cm3 of ethyl acetate and then with 2×25 cm3 of diisopropyl ether. The solid is then dried under reduced pressure (90 Pa; 50° C.) to give 1 g of 4-[(6-chloro-1H-indazol-3-yl)amino]-4-oxo-2-butenoic acid (Z form) in the form of yellow crystals melting at 230° C.

Workup

temperaturecooled in a water bath
filtrationThe insoluble material is filtered off
washwashed successively with 2×25 cm3 of ethyl acetate
customThe solid is then dried under reduced pressure (90 Pa; 50° C.)

Sources & evidence

ORD record: ord-753497c62f804f97b114565b58b850c0
Source dataset: uspto-grants-2005_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06949579B2

Linked notes

Loading…