2942-59-8

Basic information

• Product Name: 2-Chloronicotinic acid
• Synonyms: TIMTEC-BB SBB004002;2-chloro-3-pyridinecarboxylicaci;RARECHEM AL BO 0287;AKOS BBS-00004231;2-CHLORO-3-PYRIDINECARBOXYLIC ACID;2-CHLOROPYRIDINE-3-CARBOXYLIC ACID;2-CHLOROPYRIDIN-3-CARBOXYLIC ACID;2CLNA
• CAS NO: 2942-59-8
• Molecular Formula: C₆H₄ClNO₂
• Molecular Weight: 157.55
• EINECS: 220-937-0
• Product Categories: blocks;Carboxes;Pyridines;Pyridine;Acids and Derivatives;Heterocycles;Pyridines, Pyrimidines, Purines and Pteredines;Carboxylic Acids;Organic acids;Diflufenican;Chloropyridines;Halopyridines;Carboxylic Acids;pyridine series;ACID;carboxylic acid| alkyl chloride;Pharmaceutical intermediates;Imidazoles
• Mol File: 2942-59-8.mol
• Article Data: 28

Chemical Properties

• Melting Point: 176-178 °C (dec.)(lit.)
• Boiling Point: 316.8 °C at 760 mmHg
• Flash Point: 145.4 °C
• Appearance: White to cream/Powder
• Density: 1.47 g/cm³
• Vapor Pressure: 0.000168mmHg at 25°C
• Storage Temp.: Store below +30°C.
• Solubility: DMSO, Ethyl Acetate (Slightly)
• PKA: 2.07±0.25(Predicted)
• BRN: 119023
• CAS DataBase Reference: 2-Chloronicotinic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Chloronicotinic acid(2942-59-8)
• EPA Substance Registry System: 2-Chloronicotinic acid(2942-59-8)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 22-24/25-37/39-26-36
• WGK Germany: 3
• TSCA: T
• HazardClass: IRRITANT
• Hazardous Substances Data: 2942-59-8(Hazardous Substances Data)

Usage

Chemical Properties

white to cream powder. MP>175°C (decomposition), insoluble in water, soluble in organic solvents such as benzene and toluene.

Uses

2-Chloronicotinic Acid is used in the preparation of 4-thiazolidinone derivatives and Schiff bases displaying antimicrobial activity.

Application

2-Chloronicotinic acid is used in the synthesis of the anti-inflammatory and analgesic pralofen. It is an intermediate of the herbicides nicosulfuron and diflufenican. It is also used as pharmaceutical intermediates for the manufacture of mefenamic acid, niflumic acid, etc.

Preparation

Chloronicotinic acid was synthesized from nicotinic acid by oxidation by H2O2 and then chlorinationby POCl3 and PCl5 in a yield of 87.5%.Synthesis of 2-chloronicotinic acid: Pour chlorine gas into the mixed solution of phosphorus oxychloride and phosphorus trichloride, control the temperature at about 60°C, until the remaining chlorine gas escapes, cool and add nicotinic acid N-oxide in batches, and heat the mixed solution. The reaction was carried out at 100-105°C for 1-1.5 h, and the reaction mixture was stirred for 30 min after the reaction mixture was transparent, and phosphorus oxychloride was removed under reduced pressure. The obtained residue was cooled to room temperature, and water was added to obtain the finished product of 2-chloronicotinic acid.

InChI:InChI=1/C6H4ClNO2/c7-5-4(6(9)10)2-1-3-8-5/h1-3H,(H,9,10)/p-1

Synthetic route

2 chloro-3-methylpyridine (18368-76-8) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With ozone; acetic acid at 20℃; for 5h; Reagent/catalyst; Temperature;	98%
With N-hydroxyphthalimide; oxygen; cobalt(III) acetylacetonate In acetonitrile at 80℃; under 7500.75 Torr; for 18h; Reagent/catalyst; Temperature; Autoclave;	94.1%
With permanganate(VII) ion

2-chloro-3-ethylpyridine (96440-05-0) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With sodium acetate; ozone; acetic acid at 20℃; for 5h; Temperature; Reagent/catalyst;	98%
With potassium permanganate; water

2-chloro-3-isopropylpyridine → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With iron(II) acetate; ozone; acetic acid at 100℃; Reagent/catalyst; Temperature;	98%

2-chloro-3-(dichloromethyl)-pyridine → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With 10% Ru/C; oxygen; sodium carbonate In tetrahydrofuran at 140℃; under 22502.3 - 30003 Torr; for 4h; Catalytic behavior; Temperature; Solvent; Pressure; Autoclave; Green chemistry;	95.4%

ethyl 2-chloronicotinate (1452-94-4) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With sodium hydroxide at 80℃; for 2h; Temperature;	95.2%
With sodium hydroxide In methanol; water at 75℃;

2-chloro-3-(chloromethyl)pyridine (89581-84-0) + acetic acid (64-19-7) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With sodium nitrite In dimethyl sulfoxide at 20℃; for 8h; Temperature; Solvent;	95.1%

2-Chloronicotinoyl chloride (49609-84-9) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With water at 0 - 5℃; for 0.5h; pH=1.5; Alkaline conditions; Green chemistry;	92%
In water

Pyridine-2,3-dicarboxylic acid (89-00-9) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With potassium permanganate; chlorine In water at 85 - 90℃; Reagent/catalyst; Solvent;	91%

2-chloro-3-(trichloromethyl)-pyridine (72648-12-5) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With sulfuric acid; lithium acetate; water; silver; fluorosulphonic acid; acetic acid In methanol at 55 - 60℃; Electrolysis;	91%
With water

nicotinic acid (59-67-6) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
Stage #1: nicotinic acid With dihydrogen peroxide; acetic acid In toluene Reflux; Stage #2: With phosphorus pentachloride; trichlorophosphate In toluene Reflux;	90%
Multi-step reaction with 3 steps 1: molybdic acid; dihydrogen peroxide / water / 3 h / 92 - 95 °C / Green chemistry 2: trichlorophosphate; triethylamine / 6 h / 10 - 100 °C / Green chemistry 3: water / 0.5 h / 0 - 5 °C / pH 1.5 / Alkaline conditions; Green chemistry View Scheme

2-chloro-3-pyridinecarbonitrile (6602-54-6) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With water; sodium hydroxide for 3h; Reflux;	90%
With sulfuric acid at 100℃; for 10h;	88%
With water; sodium chloride; sodium hydroxide at 90℃; Reagent/catalyst; Temperature;

2-chloro-3-vinylpyridine (1033125-18-6) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With zinc diacetate; ozone In ethanol at 100℃;	87%

2-chloro-3-tert-butylpyridine → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With zinc diacetate; ozone In acetonitrile at 100℃;	85%

3-cyanopyridine N-oxide (14906-64-0) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With bis(trichloromethyl) carbonate In 5,5-dimethyl-1,3-cyclohexadiene; N,N-dimethyl-formamide for 0.0833333h; Solvent; Reagent/catalyst; Time; Reflux; Large scale; Green chemistry;	68.6%

Nicotinic acid N-oxide (2398-81-4) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With triethylamine; trichlorophosphate at 100℃; for 4h;	65%

carbon monoxide (201230-82-2) + 2-chloro-3-iodopyridine (78607-36-0) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With water; palladium diacetate; triethylamine; triphenylphosphine In 1,4-dioxane at 110℃; under 11251.1 Torr; for 2h; Flow reactor;	57%

(2-chloropyrid-3-yl)methanol (42330-59-6) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With 3,5-Lutidine; 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxyl; sodium persulfate; tris(2,2'‐bipyridine)ruthenium(II) hexafluorophosphate In water; acetonitrile at 20℃; for 48h; Sealed tube; Irradiation;	24%

2-hydroxy-3-carboxypyridine (609-71-2) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate
With sodium hydroxide; trichlorophosphate In toluene

2-chloro-3-pyridinecarbonitrile (6602-54-6) + glycine (56-40-6) → 2-chloronicotinic acid (2942-59-8) + N-(3-carboxamido-2-pyridyl)glycine (74149-43-2)

Conditions	Yield
With sodium carbonate In water for 12h; Heating;	A n/a B 1.4 g

Nicotinic acid N-oxide (2398-81-4) → 6-Chloro-3-pyridinecarboxylic acid (5326-23-8) + 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate

Nicotinic acid N-oxide (2398-81-4) → 2-chloronicotinic acid (2942-59-8) + 1-(5-Carboxy-2-pyridyl)-2-pyridon-3-carbonsaeure (117638-64-9)

Conditions	Yield
With trichlorophosphate In N,N-dimethyl-formamide Yield given;

α-chloro-nicotine → 2-chloronicotinic acid (2942-59-8)

2-oxy-nicotinic acid → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate at 140℃; Zersetzen des Reaktionsprodukts mit Wasser;

nicotinic acid-1-oxide → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate

(S)-2'-chloro-1,2,3,4,5,6-hexahydro-<2,3'>bipyridyl → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With potassium permanganate

2-<2-oxo-1,2-dihydro-pyridine-3-carbonylimino>-2H-<1,2'>bipyridyl-3'-carboxylic acid → 5H-dipyrido<1,2-a:3',2'>pyrimidin-5-one (106531-39-9) + 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate

Nicotinic acid N-oxide (2398-81-4) + phosphorus pentachloride (10026-13-8, 874483-75-7) + trichlorophosphate (10025-87-3, 12599-09-6, 63736-95-8) → 2-chloronicotinic acid (2942-59-8) + 4-chloronicotinic acid (10177-29-4)

nicotinic acid-1-oxide → 2-chloronicotinic acid (2942-59-8) + 4-chloronicotinic acid (10177-29-4)

Conditions	Yield
With phosphorus pentachloride; trichlorophosphate

ethyl 2-chloro-2-cyano-5-oxopentanoate (152361-99-4) → 2-chloronicotinic acid (2942-59-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 65 percent / PCl3, HCl(g) / dimethylformamide; toluene / 1.) 60 deg C, 30 min; 2.) 90 deg C, 1.5 h 2: NaOH / methanol; H2O / 75 °C View Scheme

diazomethane (186581-53-3, 908094-01-9) + 2-chloronicotinic acid (2942-59-8) → methyl 2-chloropyridine-3-carboxylate (40134-18-7)

Conditions	Yield
In methanol at -15℃; for 4h;	100%
In methanol; diethyl ether; ethanol	84%
	78%
With methanol; diethyl ether

2-chloronicotinic acid (2942-59-8) → 2-Chloronicotinoyl chloride (49609-84-9)

Conditions	Yield
With thionyl chloride for 3h; Heating;	100%
With oxalyl dichloride; N,N-dimethyl-formamide In dichloromethane at 25℃; for 3h; Inert atmosphere;	100%
With thionyl chloride for 3h; Heating;	99%

2-chloronicotinic acid (2942-59-8) + 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide (139756-02-8) → N-(5-carbamoyl-1-methyl-3-propyl-1H-pyrazol-4-yl)-2-chloronicotinamide (1370409-73-6)

Conditions	Yield
With triethylamine; bromo-tris(1-pyrrolidinyl)phosphonium hexafluorophosphate In 1,2-dichloro-ethane at 120℃; for 0.333333h; Microwave irradiation;	100%

2-chloronicotinic acid (2942-59-8) + methyl 3-amino-5-ethoxybenzoate (706792-04-3) → methyl 3-(2-chloronicotineamido)-5-ethoxybenzoate

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃; for 2h; Large scale;	100%

2-chloronicotinic acid (2942-59-8) + ethylamine (75-04-7) → 2-(ethylamino)-3-pyridine carboxylic acid (669087-25-6)

Conditions	Yield
at 120℃; for 4h;	99.7%
at 120℃; for 4h; Sealed vessel;	99.7%

2-chloronicotinic acid (2942-59-8) → C12H6Cl2N2O3 (75910-09-7)

Conditions	Yield
With 1-ethyl-piperidine; N,N-bis[2-oxo-3-oxazolidinyl]phosphorodiamidic chloride In tetrahydrofuran at 20℃; for 0.666667h;	99%

2-chloronicotinic acid (2942-59-8) → 3-bromo-fluorophenylmercaptan

Conditions	Yield
In N,N-dimethyl-formamide; trichlorophosphate	99%

2-chloronicotinic acid (2942-59-8) + diazomethyl-trimethyl-silane (18107-18-1) → methyl 2-chloropyridine-3-carboxylate (40134-18-7)

Conditions	Yield
In tetrahydrofuran; methanol; hexane at 20℃; for 1.5h;	99%
In methanol; hexanes; toluene at 20℃;	85.42%

2-chloronicotinic acid (2942-59-8) + 1-(4,4'-dichloro-benzhydryl)-piperazine (27469-61-0) → (4-(bis(4-chlorophenyl)methyl)piperazin-1-yl)(2-chloropyridin-3-yl)methanone

Conditions	Yield
With O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate; N-ethyl-N,N-diisopropylamine In dichloromethane at 20℃;	99%

2-chloronicotinic acid (2942-59-8) + methylamine (74-89-5) → 2-(methylamino)pyridine-3-carboxylic acid (32399-13-6)

Conditions	Yield
In water at 140℃; for 1.5h; Reactivity; Concentration; Temperature; Time; Microwave irradiation; Biotage Initiator;	98%
With sodium hydroxide In methanol at 90℃; for 48h; Temperature; Solvent; Autoclave;	93.8%
In water at 120℃; for 15h; sealed tube;	56%
With pyridine; toluene-4-sulfonic acid In water Heating;
In ethanol at 80℃; for 80h; Autoclave;

2-chloronicotinic acid (2942-59-8) + N-methyl-1H-benzo[d]imidazol-2-amine (17228-38-5) → 5,6-dihydro-6-methyl-5-oxopyrido<3',2':5,6>pyrimido<1,2-a>benzimidazole

Conditions	Yield
With Ullmann copper; potassium carbonate; potassium iodide In N,N-dimethyl-formamide at 170℃; for 5h;	98%

2-chloronicotinic acid (2942-59-8) + ethanol (64-17-5) → ethyl 2-chloronicotinate (1452-94-4)

Conditions	Yield
Stage #1: 2-chloronicotinic acid With thionyl chloride Stage #2: ethanol	98%
With dmap; dicyclohexyl-carbodiimide In N,N-dimethyl-formamide for 4h;	95%
With sulfuric acid for 2h; Reflux;	79%

2-chloronicotinic acid (2942-59-8) → methyl 2-chloropyridine-3-carboxylate (40134-18-7)

Conditions	Yield
With thionyl chloride; triethylamine In methanol; toluene	98%
Multi-step reaction with 2 steps 1: SOCl2 / 2.5 h / Heating 2: Et3N / Ambient temperature View Scheme
Multi-step reaction with 2 steps 1: thionyl chloride / 2 h / Heating 2: 1 h / Heating View Scheme
Multi-step reaction with 2 steps 1: SOCl2 / benzene / 3 h / Heating 2: 0.33 h / Heating View Scheme
With thionyl chloride In methanol

2-chloronicotinic acid (2942-59-8) + ethyl iodide (75-03-6) → ethyl 2-chloronicotinate (1452-94-4)

Conditions	Yield
With potassium carbonate In N-methyl-acetamide; water	98%
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 72h;

2-chloronicotinic acid (2942-59-8) + 4-Ethoxyaniline (156-43-4) → 2-[(4-ethoxyphenyl)amino]pyridine-3-carboxylic acid (4394-10-9)

Conditions	Yield
With potassium carbonate In water at 150℃; for 1.5h; Green chemistry;	98%
With potassium carbonate In water at 150℃; for 1h; Microwave irradiation;	86%

2-chloronicotinic acid (2942-59-8) + 1-t-Butoxycarbonylpiperazine (57260-71-6) → 1-(2-chloronicotinoyl)piperazine hydrochloride

Conditions	Yield
Stage #1: 2-chloronicotinic acid With thionyl chloride In dichloromethane at 0 - 50℃; for 4h; Reflux; Stage #2: 1-t-Butoxycarbonylpiperazine With triethylamine In dichloromethane for 1h; Stage #3: With hydrogenchloride In ethanol for 1h; Reflux;	98%

2-chloronicotinic acid (2942-59-8) + 2-methyl-3-trifluoromethylaniline (54396-44-0) → flunixin (38677-85-9)

Conditions	Yield
With perfluorosulfonic acid resin In water at 65 - 70℃; for 2.5h; Temperature; Industrial scale;	97.1%
With potassium hydroxide; toluene-4-sulfonic acid In water	83%
With pyridine; toluene-4-sulfonic acid In water Reflux;	73%
With toluene-4-sulfonic acid; copper(II) oxide; sodium hydroxide In 1,2-dimethoxyethane; water at 45℃; for 0.6h; Reagent/catalyst; Temperature;

2-chloronicotinic acid (2942-59-8) + thiophenol (108-98-5) → 2-(phenylthio)nicotinic acid (35620-72-5)

Conditions	Yield
With potassium carbonate In water at 180℃; for 2h;	97%
at 190℃;

2-chloronicotinic acid (2942-59-8) + 3-chloro-aniline (108-42-9) → 2-<(3-chlorophenyl)amino>-3-pyridinecarboxylic acid (57978-41-3)

Conditions	Yield
With toluene-4-sulfonic acid In water for 4h; Reflux;	97%
With potassium carbonate In water at 150℃; for 3h; Green chemistry;	94%
With sodium iodide at 100 - 140℃; for 3h;	94%

tert-butyl N-[(1s,4s)-4-aminocyclohexyl]carbamate (247570-24-7) + 2-chloronicotinic acid (2942-59-8) → syn-{4-[(2-chloro-pyridine-3-carbonyl)-amino]-cyclohexyl}-carbamic acid tert-butyl ester (834868-97-2)

Conditions	Yield
Stage #1: 2-chloronicotinic acid; oxalyl dichloride With N,N-dimethyl-formamide In dichloromethane at 0 - 20℃; for 3.16667h; Stage #2: tert-butyl N-[(1s,4s)-4-aminocyclohexyl]carbamate With N-ethyl-N,N-diisopropylamine In dichloromethane for 18h;	97%

2-chloronicotinic acid (2942-59-8) + 3-methylmercaptoaniline (1783-81-9) → 2-(3-Methylsulfanyl-phenylamino)-nicotinic acid (115891-07-1)

Conditions	Yield
	96%

2-chloronicotinic acid (2942-59-8) + butan-1-ol (71-36-3) → 2-n-butoxypyridine-3-carboxylic acid (28355-23-9)

Conditions	Yield
With sodium In ethyl acetate	96%
Stage #1: butan-1-ol With sodium hydride In dimethyl sulfoxide at 0℃; for 0.5h; Stage #2: 2-chloronicotinic acid In dimethyl sulfoxide at 20℃; Stage #3: With hydrogenchloride In water; dimethyl sulfoxide

2-chloronicotinic acid (2942-59-8) + p-toluidine (106-49-0) → 2-[(4-methylphenyl)amino]pyridine-3-carboxylic acid (60645-32-1)

Conditions	Yield
With potassium carbonate In water at 150℃; for 2.5h; Green chemistry;	96%
With potassium carbonate In water at 150℃; for 1h; Microwave irradiation;	81%
With pyridine; toluene-4-sulfonic acid In water; acetone at 70℃; for 8h;

Upstream product

• 18368-76-8 2 chloro-3-methylpyridine 
• 6602-54-6 2-chloro-3-pyridinecarbonitrile 
• 56-40-6 glycine 
• 1033125-18-6 2-chloro-3-vinylpyridine 
• 14906-64-0 3-cyanopyridine N-oxide 
• 56880-79-6 3-Ethyl-1-methyl-2-pyridon 
• 59-67-6 nicotinic acid 
• 152361-99-4 ethyl 2-chloro-2-cyano-5-oxopentanoate 
• 2398-81-4 Nicotinic acid N-oxide 
• 10026-13-8 phosphorus pentachloride 
• 10025-87-3 trichlorophosphate 
• 1452-94-4 ethyl 2-chloronicotinate 
• 609-71-2 2-hydroxy-3-carboxypyridine 
• 96440-05-0 2-chloro-3-ethylpyridine 

Downstream Products

• 40134-18-7 methyl 2-chloropyridine-3-carboxylate 
• 609-71-2 2-hydroxy-3-carboxypyridine 
• 99973-09-8 2-hydroxy-nicotinic acid-[2]pyridylamide 
• 109255-91-6 2-(2-hydroxy-nicotinoylimino)-2H-[1,2']bipyridyl-3'-carboxylic acid 
• 35620-72-5 2-(phenylthio)nicotinic acid 
• 16344-24-4 2-(phenylamino)nicotinic acid 
• 35620-71-4 2-phenoxypyridine-3-carboxylic acid 
• 115891-10-6 2-(2,4-difluorophenylamino)nicotinic acid 
• 16498-81-0 2-methoxynicotinic acid 
• 57978-47-9 2-(3-Methoxy-phenylamino)-nicotinic acid 
• 114501-02-9 2-(o-methoxyanilino)nicotinic acid 
• 75910-24-6 2-(2-Methylsulfanyl-phenylamino)-nicotinic acid 
• 343221-63-6 2-[(2,4-dichlorophenyl)amino]pyridine-3-carboxylic acid 
• 4394-00-7 Niflumic Acid 

Relevant articles and documents

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The invention discloses a method for preparing aldehyde and an acid by electrochemical dechlorination of a polychloromethylpyridine derivative, the method comprises the following steps: dissolving thepolychloromethylpyridine derivative in an acetic acid and acetate- containing buffer solution to obtain an electrolytic reaction solution; taking the electrolytic reaction solution as a cathode liquid, performing electrolytic reduction dechlorination reaction at a cathode, and hydrolyzing in the solution to obtain a polychlorinated pyridylaldehyde or acid derivative. The polychloromethylpyridinederivative is shown in formula (I), and the product polychlorinated pyridylaldehyde or acid derivative is shown in formula (II): in the formula (I), m is 0, 1, 2, 3 or 4, n is 0 or 1, and R' is an easy-to-oxidize or easy-to-hydrolyze substituent. The m and the R' in the formula (II) are same as that in the formula (I), R is H or OH, no waste acid is generated in the preparation process, the easy-to-oxidize or easy-to-hydrolyze substituent contained in the polychloromethylpyridine derivative and carbon-chlorine bonds on pyridine rings are not affected, and the recovery conversion rate is high.