944129-07-1

Basic information

• Product Name: 4-Chloro-2-fluoro-3-methoxyphenylboronic acid
• Synonyms: 4-Chloro-2-fluoro-3-methoxyphenylboronic acid
• CAS NO: 944129-07-1
• Molecular Formula: C₇H₇BClFO₃
• Molecular Weight: 204.3910832
• Mol File: 944129-07-1.mol
• Article Data: 6

Chemical Properties

• Boiling Point: 342.7±52.0 °C(Predicted)
• Appearance: /
• Density: 1.40±0.1 g/cm3(Predicted)
• Storage Temp.: Room temperature.
• Solubility: Dichloromethane
• PKA: 7.71±0.58(Predicted)
• CAS DataBase Reference: 4-Chloro-2-fluoro-3-methoxyphenylboronic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Chloro-2-fluoro-3-methoxyphenylboronic acid(944129-07-1)
• EPA Substance Registry System: 4-Chloro-2-fluoro-3-methoxyphenylboronic acid(944129-07-1)

Safety Data

• Hazardous Substances Data: 944129-07-1(Hazardous Substances Data)

Usage

Chemical Properties

White powder

Uses

4-Chloro-2-fluoro-3-methoxyphenylboronic Acid is an intermediate in the synthesis of Arylex (A794890), which exhibits potent dicot weed control; Herbicide.

Synthetic route

1-chloro-3-fluoro-2-methoxybenzene (53145-38-3) → (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1)

Conditions	Yield
Stage #1: 1-chloro-3-fluoro-2-methoxybenzene With n-butyllithium In 1,2-dimethoxyethane at -78 - -70.1℃; for 1.75h; Stage #2: With Trimethyl borate In 1,2-dimethoxyethane at -67 - 20℃; Time; Temperature; Further stages;	93%
Multi-step reaction with 2 steps 1.1: n-butyllithium / 1,2-dimethoxyethane; hexane / 1.75 h / -77 - -70.1 °C / Inert atmosphere 1.2: 1.37 h / -74.1 - 23.1 °C 2.1: potassium hydroxide; water / 1,2-dimethoxyethane / 2 h / 30 °C / Cooling View Scheme

Trimethyl borate (121-43-7) + 1-chloro-3-fluoro-2-methoxybenzene (53145-38-3) → (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1)

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane; cyclohexane at -50℃; Flow reactor;	92%
Stage #1: 1-chloro-3-fluoro-2-methoxybenzene With n-butyllithium In 1,2-dimethoxyethane at -65℃; Inert atmosphere; Stage #2: Trimethyl borate In 1,2-dimethoxyethane at -65 - 30℃; Time; Inert atmosphere;

Trimethyl borate (121-43-7) + 6-chloro-2-fluoro-3-lithioanisole → (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1)

Conditions	Yield
Stage #1: Trimethyl borate; 6-chloro-2-fluoro-3-lithioanisole In 1,2-dimethoxyethane; hexane at -70 - -45℃; for 0.25h; Cooling with dry ice bath; Stage #2: With hydrogenchloride; water In 1,2-dimethoxyethane; hexane Product distribution / selectivity;
Stage #1: Trimethyl borate; 6-chloro-2-fluoro-3-lithioanisole In hexanes; 1,2-dimethoxyethane at -65 - 20℃; Stage #2: With potassium hydroxide; water In hexanes; 1,2-dimethoxyethane at 23.1℃; for 1.11667h; Stage #3: With hydrogenchloride In water; acetonitrile Product distribution / selectivity;
Stage #1: Trimethyl borate; 6-chloro-2-fluoro-3-lithioanisole In hexanes; 1,2-dimethoxyethane at -65 - 20℃; Stage #2: With potassium hydroxide; water In hexanes; 1,2-dimethoxyethane at 23.3℃; for 1.43333h; Stage #3: With hydrogenchloride In water Product distribution / selectivity;

4-chloro-2-fluoro-3-methoxyphenyl dimethylboronate (1426539-30-1) → (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1)

Conditions	Yield
Stage #1: 4-chloro-2-fluoro-3-methoxyphenyl dimethylboronate With water; potassium hydroxide at 16 - 20℃; for 0.25h; Stage #2: With hydrogenchloride In water for 0.25h;
With water; potassium hydroxide In 1,2-dimethoxyethane at 30℃; for 2h; Cooling;

2,3-dimethyl-2,3-butane diol (76-09-5) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → 2-(4-chloro-2-fluoro-3-methoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1126321-06-9)

Conditions	Yield
In ethyl acetate at 23.1℃; for 2h; Inert atmosphere;	99%

methyl 4-amino-3,6-dichloro-5-fluoropicolinate (496850-09-0) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)-5-fluoropyridine-2-carboxylic acid methyl ester

Conditions	Yield
With palladium diacetate; potassium carbonate; triphenylphosphine In methanol; water; acetonitrile at 60℃; for 7h; Suzuki Coupling;	88.1%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + C14H18Cl3NO2 → C21H23Cl3FNO3

Conditions	Yield
With dichloro[9,9-dimethyl-4,5- bis(diphenylphosphino)xanthene]palladium (II); triethylamine In water; toluene at 55℃; for 24h; Catalytic behavior; Reagent/catalyst; Temperature; Solvent; Suzuki-Miyaura Coupling; Inert atmosphere;	85%

methyl 4-amino-3,6-dichloropyridine-2-carboxylate (350601-39-7) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → halauxifen methyl ester

Conditions	Yield
With palladium diacetate; potassium carbonate; triphenylphosphine In water; acetonitrile at 50℃; for 22h; Concentration; Reagent/catalyst; Suzuki Coupling; Inert atmosphere;	81.4%
With bis-triphenylphosphine-palladium(II) chloride; potassium fluoride In water; acetonitrile for 4h; Reflux;

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + benzyl 4,5,6-trichloropicolinate (1390662-56-2) → benzyl 4,5-dichloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (1390662-58-4)

Conditions	Yield
With dichloro[9,9-dimethyl-4,5- bis(diphenylphosphino)xanthene]palladium (II); triethylamine In water; toluene at 35℃; for 18h; Catalytic behavior; Reagent/catalyst; Temperature; Solvent; Suzuki-Miyaura Coupling; Inert atmosphere;	79%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + methyl 6-amino-2-chloro-5-methoxy-pyrimidine-4-carboxylate (1126320-49-7) → methyl 6-amino-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-methoxypyrimidine-4-carboxylate (1126318-85-1)

Conditions	Yield
With palladium diacetate; potassium hydrogencarbonate; triphenylphosphine In methanol; water; acetonitrile at 50℃; for 22h; Suzuki Coupling; Inert atmosphere;	75.6%
With cesium fluoride; bis-triphenylphosphine-palladium(II) chloride In 1,2-dimethoxyethane; water at 100℃; for 0.25h; Microwave irradiation;	51.1%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 4,5,6-trichloropicolinic acid (496849-77-5) → 6-(4-chloro-2-fluoro-3-methoxyphenyl)-4,5-dichloro-2-pyridinecarboxylic acid (1546765-39-2) + 5-chloro-4,6-bis(4-chloro-2-fluoro-3-methoxyphenyl)picolinic acid

Conditions	Yield
Stage #1: 4,5,6-trichloropicolinic acid With palladium diacetate; triethylamine In water; acetonitrile for 0.5h; Inert atmosphere; Stage #2: (4-chloro-2-fluoro-3-methoxyphenyl)-boronic acid With triethylamine In water; acetonitrile at 65℃; for 24.5h; Reagent/catalyst; Inert atmosphere;	A 74% B 6%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + [(3-methoxyphenyl)methylidene]hydrazine (108087-83-8) → C15H14ClFO2

Conditions	Yield
With manganese(IV) oxide; N-ethyl-N,N-diisopropylamine In dichloromethane at 25℃; under 5171.62 Torr; Flow reactor;	71%

6-amino-2,5-dichloro-pyrimidine-4-carboxylic acid methyl ester (502142-81-6) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 6-amino-5-chloro-2-(4-chloro-2-fluoro-3-methoxyphenyl)pyrimidine-4-carboxylate

Conditions	Yield
With palladium diacetate; potassium hydrogencarbonate; triphenylphosphine In methanol; water; acetonitrile at 50℃; for 22h; Suzuki Coupling; Inert atmosphere;	68.1%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + benzyl 4-amino-3,6-dichloro-5-fluoropicolinate → benzyl ester of 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylic acid (1390661-72-9)

Conditions	Yield
With palladium diacetate; potassium carbonate; triphenylphosphine In methanol; water; acetonitrile at 60℃; for 4h; Suzuki Coupling;	67.9%

methyl 5-chloropyridine-2-carboxylate (132308-19-1) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → 5-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylic acid

Conditions	Yield
Stage #1: methyl 5-chloropyridine-2-carboxylate; (4-chloro-2-fluoro-3-methoxyphenyl)-boronic acid With (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; potassium carbonate; triphenylphosphine In N,N-dimethyl-formamide at 85 - 90℃; for 24h; Suzuki Coupling; Inert atmosphere; Stage #2: With water; lithium hydroxide In tetrahydrofuran at 25 - 30℃; for 3h; Inert atmosphere;	60%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 4-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole → 4-(4-chloro-2-fluoro-3-methoxy-phenyl)-1-tetrahydropyran-2-yl-pyrazole

Conditions	Yield
With dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH2Cl2; potassium carbonate In 1,4-dioxane; water at 110℃; for 2h; Suzuki Coupling;	54%

methyl 6-amino-2-chloropyrimidine-4-carboxylate (944129-00-4) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → 6-amino-2-(4-chloro-2-fluoro-3-methoxy-phenyl)-pyrimidine-4-carboxylic acid methyl ester (944129-05-9)

Conditions	Yield
bis-triphenylphosphine-palladium(II) chloride In 1,2-dimethoxyethane; water at 80℃; for 2h;	53.3%
bis-triphenylphosphine-palladium(II) chloride In 1,2-dimethoxyethane; water at 80℃; for 2h;	53.5%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + C11H7Cl3N4O2 → C18H12Cl3FN4O3

Conditions	Yield
With dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH2Cl2; cesium fluoride In 1,4-dioxane; water at 120℃; for 12h; Inert atmosphere;	51%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 4-amino-2-chloro-6-methoxycarbonyl-5-prop-1-ynyl-pyrimidine (1240313-17-0) → 4-amino-2-(4-chloro-2-fluoro-3-methoxyphenyl)-6-methoxycarbonyl-5-prop-1-ynyl-pyrimidine (1240312-70-2)

Conditions	Yield
With cesium fluoride; dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH2Cl2 In 1,2-dimethoxyethane; water at 140℃; for 0.333333h; Haller-Bauer Reaction; Inert atmosphere; microwave irradiation;	11%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 4,5,6-trichloro-pyridine-2-carboxylic acid methyl ester (496849-76-4) → C14H9Cl3FNO3

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; potassium fluoride In water; ethyl acetate at 45℃; for 18h; Suzuki-Miyaura Coupling; Inert atmosphere;	5%

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + trimethyleneglycol (504-63-2) → 1,3-propanediyl 4-chloro-2-fluoro-3-methoxyphenylboronate

Conditions	Yield
In 1,2-dimethoxyethane; hexane
In toluene for 2h; Heating / reflux;

4-acetylamino-3-benzyloxy-6-bromo-pyridine-2-carboxylic acid methyl ester (851442-71-2) + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 4-acetamido-3-(benzyloxy)-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (1417332-47-8)

Conditions	Yield
With cesium fluoride; bis-triphenylphosphine-palladium(II) chloride In 1,2-dimethoxyethane; water at 100℃; for 0.25h; microwave irradiation;

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 4-acetamido-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-hydroxypicolinate (1417332-44-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: cesium fluoride / bis-triphenylphosphine-palladium(II) chloride / 1,2-dimethoxyethane; water / 0.25 h / 100 °C / microwave irradiation 2: hydrogen / 10 wt% Pd(OH)2 on carbon / ethanol / 24 h View Scheme

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 4-acetamido-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-methoxypicolinate (1417331-18-0)

Conditions	Yield
Multi-step reaction with 3 steps 1: cesium fluoride / bis-triphenylphosphine-palladium(II) chloride / 1,2-dimethoxyethane; water / 0.25 h / 100 °C / microwave irradiation 2: hydrogen / 10 wt% Pd(OH)2 on carbon / ethanol / 24 h 3: triphenylphosphine; diethylazodicarboxylate / tetrahydrofuran / 24 h View Scheme

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 4-amino-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-methoxypicolinate (1417331-20-4)

Conditions	Yield
Multi-step reaction with 4 steps 1: cesium fluoride / bis-triphenylphosphine-palladium(II) chloride / 1,2-dimethoxyethane; water / 0.25 h / 100 °C / microwave irradiation 2: hydrogen / 10 wt% Pd(OH)2 on carbon / ethanol / 24 h 3: triphenylphosphine; diethylazodicarboxylate / tetrahydrofuran / 24 h 4: methanol / 25 °C View Scheme

methyl 4-(acetylamino)-3,6-dichloropyridine-2-carboxylate + (4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → methyl 4-(acetylamino)-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate (943831-44-5)

Conditions	Yield
Stage #1: methyl 4-(acetylamino)-3,6-dichloropyridine-2-carboxylate; (4-chloro-2-fluoro-3-methoxyphenyl)-boronic acid With palladium diacetate; triphenylphosphine In 1,2-dimethoxyethane; acetonitrile Inert atmosphere; Stage #2: With potassium carbonate In 1,2-dimethoxyethane; water; acetonitrile at 50℃; for 2.5h;

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 4,5,6-trichloropicolinic acid (496849-77-5) → 6-(4-chloro-2-fluoro-3-methoxyphenyl)-4,5-dichloro-2-pyridinecarboxylic acid (1546765-39-2)

Conditions	Yield
Stage #1: 4,5,6-trichloropicolinic acid With bis-triphenylphosphine-palladium(II) chloride; triethylamine In water; acetonitrile at 50℃; for 0.25h; Inert atmosphere; Stage #2: (4-chloro-2-fluoro-3-methoxyphenyl)-boronic acid In 1,2-dimethoxyethane; water; acetonitrile at 50℃; for 5h; Inert atmosphere;

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → 6-(4-chloro-2-fluoro-3-methoxyphenyl)-4,5-dichloro-2-pyridinecarbonyl chloride (1546765-42-7)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: triethylamine; bis-triphenylphosphine-palladium(II) chloride / water; acetonitrile / 0.25 h / 50 °C / Inert atmosphere 1.2: 5 h / 50 °C / Inert atmosphere 2.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 75 °C View Scheme

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) → C13H6ClF4NO2 (1546765-44-9)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: triethylamine; bis-triphenylphosphine-palladium(II) chloride / water; acetonitrile / 0.25 h / 50 °C / Inert atmosphere 1.2: 5 h / 50 °C / Inert atmosphere 2.1: thionyl chloride; N,N-dimethyl-formamide / toluene / 75 °C 3.1: potassium fluoride / sulfolane / 20 - 130 °C View Scheme

(4-chloro-2-fluoro-3-methoxy-phenyl)boronic acid (944129-07-1) + 5,6-dichloro-2-pyridinecarboxylic acid (88912-24-7) → C13H8Cl2FNO3

Conditions	Yield
Stage #1: 5,6-dichloro-2-pyridinecarboxylic acid With triethylamine In water; acetonitrile for 0.5h; Stage #2: (4-chloro-2-fluoro-3-methoxyphenyl)-boronic acid With (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; palladium diacetate In water; acetonitrile at 55℃; for 22h;

Upstream product

• 1426539-30-1 4-chloro-2-fluoro-3-methoxyphenyl dimethylboronate 
• 121-43-7 Trimethyl borate 
• 53145-38-3 1-chloro-3-fluoro-2-methoxybenzene 

Downstream Products

• 943831-44-5 methyl 4-(acetylamino)-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate 
• 1390661-72-9 benzyl ester of 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylic acid 
• 1546765-39-2 6-(4-chloro-2-fluoro-3-methoxyphenyl)-4,5-dichloro-2-pyridinecarboxylic acid 
• 1390662-58-4 benzyl 4,5-dichloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate 
• 1292286-48-6 methyl 5-chloro-2-(4-chloro-2-fluoro-3-methoxyphenyl)-6-(methylthio)pyrimidine-4-carboxylate 
• 943831-98-9 halauxifen methyl ester 
• 1546765-42-7 6-(4-chloro-2-fluoro-3-methoxyphenyl)-4,5-dichloro-2-pyridinecarbonyl chloride 
• 1126321-06-9 2-(4-chloro-2-fluoro-3-methoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane 
• 1417331-20-4 methyl 4-amino-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-methoxypicolinate 
• 1417331-18-0 methyl 4-acetamido-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-methoxypicolinate 
• 1417332-44-5 methyl 4-acetamido-6-(4-chloro-2-fluoro-3-methoxyphenyl)-3-hydroxypicolinate 
• 1417332-47-8 methyl 4-acetamido-3-(benzyloxy)-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate 
• 1240312-70-2 4-amino-2-(4-chloro-2-fluoro-3-methoxyphenyl)-6-methoxycarbonyl-5-prop-1-ynyl-pyrimidine 
• 1126318-85-1 methyl 6-amino-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-methoxypyrimidine-4-carboxylate 

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