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112811-71-9
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Basic Information
CAS No.: 112811-71-9
Name: 1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid ethyl ester
Article Data: 15
Molecular Structure:
Molecular Structure of 112811-71-9 (1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid ethyl ester)
Formula: C16H15F2NO4
Molecular Weight: 323.296
Synonyms: Ethyl1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylate;Ethyl1-cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-1,4-dihydro-3-quinolinecarboxylate;3-Quinolinecarboxylicacid, 1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-, ethyl ester;
EINECS: 620-302-1
Density: 1.415 g/cm3
Melting Point: 179-181 °C
Boiling Point: 459.695 °C at 760 mmHg
Flash Point: 231.816 °C
Appearance: Pale yellow solid
PSA: 57.53000
LogP: 2.79990
Related products
Synthetic route

ethyl α(Z)-[(diethylamino)methylene]-2,4,5-trifluoro-3-methoxy-β-oxo-benzenepropanoate

765-30-0

Cyclopropylamine

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Stage #1: ethyl α(Z)-[(diethylamino)methylene]-2,4,5-trifluoro-3-methoxy-β-oxo-benzenepropanoate; Cyclopropylamine In diethyl ether; ethanol at 20℃; for 3h;
Stage #2: With potassium carbonate In N,N-dimethyl-formamide at 100℃; for 5h;		82%

ethyl 2-(3-methoxy-2,4,5-trifluorobenzoyl)-3-(cyclopropylamino)acrylate

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
With sodium hydride In tetrahydrofuran for 18h;81%
In tetrahydrofuran; mineral oil75%
With sodium hydride In tetrahydrofuran at 20 - 40℃; for 2h;
16173-58-3

N,N-dimethylaminoacrylic acid ethyl ester

765-30-0

Cyclopropylamine

112811-66-2

2,4,5-trifluoro-3-methoxybenzoyl chloride

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Stage #1: N,N-dimethylaminoacrylic acid ethyl ester; 2,4,5-trifluoro-3-methoxybenzoyl chloride With triethylamine In ethyl acetate at 60 - 80℃; for 3h;
Stage #2: Cyclopropylamine With acetic acid In ethyl acetate for 0.5h; Temperature;		63.16%
...Expand
112811-70-8

ethyl 3-(cyclopropylamino)-2-(2,4,5-trifluoro-3-methoxybenzoyl)acrylate

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
With potassium carbonate In N,N-dimethyl-formamide at 100℃; for 5h;
With potassium carbonate In N,N-dimethyl-formamide at 100℃; for 5h;627 mg
With potassium carbonate In dimethyl sulfoxide
925457-02-9

ethyl α(E)-[(diethylamino)methylene]-2,4,5-trifluoro-3-methoxy-β-oxo-benzenepropanoate

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 2 steps
1: ethanol; diethyl ether / 3 h / 20 °C
2: 627 mg / K2CO3 / dimethylformamide / 5 h / 100 °C
View Scheme
112811-65-1

3-methoxy-2,4,5-trifluorobenzoic acid

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 4 steps
1: oxalyl chloride; DMF / CH2Cl2 / 24 h / 20 °C
2: 1.88 g / Et3N / toluene / 5 h / 90 °C
3: ethanol; diethyl ether / 3 h / 20 °C
4: 627 mg / K2CO3 / dimethylformamide / 5 h / 100 °C
View Scheme
Multi-step reaction with 5 steps
1: oxalyl chloride, DMF / CH2Cl2 / 18 h / Ambient temperature
2: 1.) n-BuLi, 2,2'-bipyridyl / 1.) THF, hexane, from -20 deg C to -5 deg C, 2.) THF, hexane, -30 deg C, 2 h
3: acetic anhydride / 22 h / Heating
4: ethanol / 18 h / Ambient temperature
5: 81 percent / NaH / tetrahydrofuran / 18 h
View Scheme
Multi-step reaction with 4 steps
1: oxalyl dichloride / N,N-dimethyl-formamide; dichloromethane / 24 h
2: triethylamine / toluene / 5 h / 90 °C
3: diethyl ether; ethanol / 3 h / 25 °C
4: potassium carbonate / N,N-dimethyl-formamide / 5 h / 90 °C
View Scheme
112811-66-2

2,4,5-trifluoro-3-methoxybenzoyl chloride

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 3 steps
1: 1.88 g / Et3N / toluene / 5 h / 90 °C
2: ethanol; diethyl ether / 3 h / 20 °C
3: 627 mg / K2CO3 / dimethylformamide / 5 h / 100 °C
View Scheme
Multi-step reaction with 3 steps
1: NEt3 / toluene / 5 h / 90 °C
2: ethanol; diethyl ether / 3 h / 20 °C
3: potassium carbonate / dimethylformamide / 5 h / 100 °C
View Scheme
Multi-step reaction with 4 steps
1: 1.) n-BuLi, 2,2'-bipyridyl / 1.) THF, hexane, from -20 deg C to -5 deg C, 2.) THF, hexane, -30 deg C, 2 h
2: acetic anhydride / 22 h / Heating
3: ethanol / 18 h / Ambient temperature
4: 81 percent / NaH / tetrahydrofuran / 18 h
View Scheme

ethyl 3-(N,N-diethylamino)acrylate

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 3 steps
1: NEt3 / toluene / 5 h / 90 °C
2: ethanol; diethyl ether / 3 h / 20 °C
3: potassium carbonate / dimethylformamide / 5 h / 100 °C
View Scheme
722542-90-7

(Z)-3-Diethylamino-2-(2,4,5-trifluoro-3-methoxy-benzoyl)-acrylic acid ethyl ester

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 2 steps
1: ethanol; diethyl ether / 3 h / 20 °C
2: potassium carbonate / dimethylformamide / 5 h / 100 °C
View Scheme
Multi-step reaction with 2 steps
1: diethyl ether; ethanol / 3 h / 25 °C
2: potassium carbonate / N,N-dimethyl-formamide / 5 h / 90 °C
View Scheme
136897-64-8

methyl 3-methoxy-2,4,5-trifluorobenzoate

112811-71-9

ethyl 8-methoxy-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylate

Conditions
ConditionsYield
Multi-step reaction with 6 steps
1: 61 percent / 1.0 N aq. NaOH / methanol / 3 h / Ambient temperature
2: oxalyl chloride, DMF / CH2Cl2 / 18 h / Ambient temperature
3: 1.) n-BuLi, 2,2'-bipyridyl / 1.) THF, hexane, from -20 deg C to -5 deg C, 2.) THF, hexane, -30 deg C, 2 h
4: acetic anhydride / 22 h / Heating
5: ethanol / 18 h / Ambient temperature
6: 81 percent / NaH / tetrahydrofuran / 18 h
View Scheme
Raw Materials
112811-68-4
112811-66-2
136897-64-8
112811-65-1
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154093-72-8
112811-72-0
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Chemistry

Following is the structure of 1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid ethyl ester (CAS NO.112811-71-9):
                                   
Empirical Formula: C16H15F2NO4
Molecular Weight: 323.2914 g/mol
Molar Refractivity: 75.852 cm3
Molar Volume: 228.539 cm3
Density: 1.415 g/cm3
Flash Point: 231.816 °C
Melting point: 179-181 °C
Index of Refraction: 1.578
Surface Tension: 52.654 dyne/cm
Enthalpy of Vaporization: 72.023 kJ/mol
Boiling Point: 459.695 °C at 760 mmHg
Product Categories: Intermediates & Fine Chemicals; Pharmaceuticals
Appearance: Pale Yellow Solid
SMILES: Fc3c(F)c(OC)c1c(C(=O)\C(=C/N1C2CC2)C(=O)OCC)c3
InChI: InChI=1/C16H15F2NO4/c1-3-23-16(21)10-7-19(8-4-5-8)13-9(14(10)20)6-11(17)12(18)15(13)22-2/h6-8H,3-5H2,1-2H3
InChIKey: XPAOPAPDCRLMTR-UHFFFAOYAY

Uses

1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid ethyl ester (CAS NO.112811-71-9) can be used as Gatifloxacin intermediate .

Specification

 1-Cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-3-quinolinecarboxylic acid ethyl ester , its cas register number is 112811-71-9. It also can be called 3-quinolinecarboxylic acid, 1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methoxy-4-oxo-, ethyl ester ; and Ethyl 1-cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylate .