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

HRID 73171Notes

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-carboxylic 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-ebf3432796e14c9d849b529d4239bfc0
Source dataset: uspto-grants-2014_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08829030B2

Reaction notes

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