• Name

  2-(3,4-Dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

• EINECS 1592732-453-0
• CAS No. 277299-70-4
• Article Data4
• CAS DataBase
• Density 1.121 g/cm³
• Solubility
• Melting Point 121.0 to 125.0 °C
• Formula C₁₂H₁₄N₂O
• Boiling Point 338.5±52.0 °C(Predicted)
• Molecular Weight 202.256
• Flash Point
• Transport Information
• Appearance
• Safety
• Risk Codes
• Molecular Structure
• Hazard Symbols
• Synonyms 1-(3,4-dimethylphenyl)-3-methyl-1H-pyrazol-5-ol;STOCK6S-35344;ZINC09530926;
• PSA 37.79000
• LogP 2.09080

Synthetic route

141-97-9

ethyl acetoacetate

60481-51-8, 86746-50-1

3,4-dimethylphenylhydrazine hydrochloride

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

Conditions

Conditions	Yield
With sodium bicarbonate; sodium acetate In diethyl ether; acetic acid	76%
With sodium acetate In acetic acid for 24h; Heating / reflux;	76%
With sodium acetate; acetic acid for 24h; Reflux;	76%

141-97-9

ethyl acetoacetate

13636-53-8

3,4-dimethylphenylhydrazine

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

Conditions

Conditions	Yield
In acetic acid	64%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

28165-50-6

2-amino-6-bromophenol

1-(3,4-dimethylphenyl)-3-methyl-4-(3-bromo-2-hydroxyphenyl)hydrazono-5-pyrazolone

Conditions

Conditions	Yield
Stage #1: 2-amino-6-bromophenol With hydrogenchloride; sodium nitrite In ethanol; water at 0 - 10℃; Stage #2: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one With triethylamine In ethanol; water at 20 - 30℃; for 2h; Reagent/catalyst;	98%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

376591-97-8

3'-amino-2'-hydroxy-1,1'-biphenyl-3-carboxylic acid hydrochloride

376591-99-0

3’-{N’-[1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1,5-di-hydropyrazol-4-ylidene]hydrazino}-2’-hydroxybiphenyl-3-carboxylic acid

Conditions

Conditions	Yield
Stage #1: 3'-amino-2'-hydroxy-1,1'-biphenyl-3-carboxylic acid hydrochloride With hydrogenchloride; sodium nitrite In methanol; water for 2.5h; pH=1-2; Stage #2: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one With sodium hydrogencarbonate In methanol; water at 20℃; for 12h; pH=8; Stage #3: With hydrogenchloride In methanol; water at 0 - 20℃; for 3h; pH=1-2;	90%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

1571-72-8

3-amino-4-hydroxybenzoic acid

3-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-4-hydroxybenzoic acid

Conditions

Conditions	Yield
	82%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

4-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-3-hydroxybenzoic acid

Conditions

Conditions	Yield
	82%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

376592-93-7

3′-amino-2′-hydroxy biphenyl-3-carboxylic acid

121-44-8

triethylamine

eltrombopag triethylamine salt

Conditions

Conditions	Yield
Stage #1: 3'-amino-2'-hydroxy-1,1'-biphenyl-3-carboxylic acid With hydrogenchloride; sodium nitrite In methanol; water at 0 - 10℃; for 1.25h; Stage #2: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one; triethylamine at 0 - 60℃; for 4h; pH=6 - 8; pH-value;	76%

...Expand

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

95-55-6

2-amino-phenol

eltrombopag olamine

Conditions

Conditions	Yield
Stage #1: 2-amino-phenol With hydrogenchloride; sodium nitrite In methanol; water at 75 - 80℃; for 24h; Stage #2: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one With triethylamine In methanol; water at 0 - 25℃; for 2.5h;	68%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

376591-78-5

C13H11NO3*ClH

376591-84-3

4'-{N'-[1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1,5-dihydropyrazol-4-ylidene]hydrazino}-3'-hydroxybiphenyl-4-carboxylic acid

Conditions

Conditions	Yield
Stage #1: C13H11NO3*ClH With hydrogenchloride; sodium nitrite In water at 5℃; for 0.166667h; Stage #2: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one With sodium hydrogencarbonate In ethanol; water at 20℃; for 24h; pH=7 - 8;	35%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

88-23-3

2-amino-4-chlorophenol-6-sulfonic acid

5-chloro-3-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxybenzenesulfonic acid

Conditions

Conditions	Yield
	34%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

570-23-0

3-aminosalicylic acid

3-{[1-(3,4-dimethylphenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl]azo}-2-hydroxybenzoic acid

Conditions

Conditions	Yield
	32%

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

376592-93-7

3′-amino-2′-hydroxy biphenyl-3-carboxylic acid

eltrombopag olamine

Conditions

Conditions	Yield
Multi-step reaction with 2 steps 1.1: hydrogenchloride; sodium nitrite / methanol; water / 1.25 h / 0 - 10 °C 1.2: 4 h / 0 - 60 °C / pH 6 - 8 2.1: methanol / 7.5 h / 25 - 60 °C View Scheme

277299-70-4

2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one

13073-25-1

2-bromo-6-nitro-phenol

25487-66-5

3-Carboxyphenylboronic acid

Eltrombopag

Conditions

Conditions	Yield
Stage #1: 2-bromo-6-nitro-phenol With benzyl bromide; potassium carbonate In acetonitrile at 90℃; for 3h; Stage #2: 3-Carboxyphenylboronic acid With potassium carbonate; palladium dichloride In 1,4-dioxane; water at 50℃; under 7500.75 Torr; for 4h; Inert atmosphere; Stage #3: 2-(3,4-dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one Further stages;

...Expand

2-(3,4-Dimethylphenyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one Specification