4-(3,4-Dimethoxyphenyl)-1H-pyrazol-5-amine synthesis

5synthesis methods

Product Name:4-(3,4-Dimethoxyphenyl)-1H-pyrazol-5-amine
CAS Number:278600-50-3
Molecular formula:C11H13N3O2
Molecular Weight:219.24

2-(3,4-dimethoxyphenyl)-3-oxopropanenitrile

96729-80-5
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4-(3,4-Dimethoxyphenyl)-1H-pyrazol-5-amine

278600-50-3
13 suppliers
$85.00/250mg

Yield:278600-50-3 75%

Reaction Conditions:

with hydrazine hydrochloride;acetic acid in ethanol at 85;Inert atmosphere;

Steps:

99-101.B.2 Step-2

To a solution of 7 (4.5 g, 21.95 mmol) in ethanol (90 mL) was added hydrazine monohydrochloride (2.25 g, 32.92 mmol) and acetic acid (12 mL) at room temperature under nitrogen atmosphere. The reaction mixture was heated to 85° C. and stirred for 3-4 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was cooled to room temperature. The reaction mixture was quenched with water (45 mL), concentrated under reduced pressure. The resultant aqueous layer was washed with toluene (3×45 mL) and basified with 10% aq. sodium bicarbonate solution (pH: 8-9). The aqueous layer was extracted with dichloromethane (4×50 mL). Combined organic layer was washed with water, brine, dried over sodium sulphate and concentrated under reduced pressure to afford 8 (3.5 g, 75%) as an off-white solid. The product obtained was used without further purification.

References:

US2016/318937,2016,A1 Location in patent:Paragraph 0300; 0301; 0303