Lithium hydroxide, monohydrate → 3-[N-(2,4-Dichloro-benzoyl)-N',N'-dimethyl-hydrazino]-5-phenyl-thiophene-2-carboxylic acid

HRID 749346Notes

Reaction equation

C[O:2][C:3]([C:5]1[S:6][C:7]([C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)=[CH:8][C:9]=1[N:10]([C:14](=[O:23])[C:15]1[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][C:16]=1[Cl:22])[N:11]([CH3:13])[CH3:12])=[O:4].O[Li].O>C1COCC1.CO.O>[Cl:22][C:16]1[CH:17]=[C:18]([Cl:21])[CH:19]=[CH:20][C:15]=1[C:14]([N:10]([C:9]1[CH:8]=[C:7]([C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)[S:6][C:5]=1[C:3]([OH:4])=[O:2])[N:11]([CH3:13])[CH3:12])=[O:23]

Participants

Conditions

Temperature: 60 °C

Procedure

3-[N-(2,4-Dichloro-benzoyl)-N′,N′-dimethyl-hydrazino]-5-phenyl-thiophene-2-carboxylic acid methyl ester (0.050 g, 0.11 mmol) was taken in a mixture of THF:MeOH:H2O (3:2:1, 10 mL) and then added 1N aqueous solution of LiOH.H2O (0.67 mL, 0.67 mmol). The reaction mixture was stirred at 60° C. for 2 h. Solvents were removed and the residue was partitioned between water and ethyl acetate. The aqueous layer was acidified using 10% KHSO4 solution. The organic layer was separated, dried (Na2SO4) and concentrated. The residue was purified by preparative TLC using dicholomethane:methanol (9:1) to obtain 3-[N-(2,4-Dichloro-benzoyl)-N′,N′-dimethyl-hydrazino]-5-phenyl-thiophene-2-carboxy-lic acid (Compound 72) (0.008 g, 17%). 1H NMR (DMSO, 400 MHz): δ 7.81 (d, 2H), 7.69 (d, 2H), 7.54-7.40 (m, 5H), 2.42 (s, 6H).

Workup

customSolvents were removed
customthe residue was partitioned between water and ethyl acetate
customThe organic layer was separated
dry with materialdried (Na2SO4)
concentrationconcentrated
customThe residue was purified by preparative TLC

Sources & evidence

ORD record: ord-9251865d76684d51becc9020e65fba68
Source dataset: uspto-grants-2008_07
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07402608B2

Reaction notes

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