2402-77-9

Basic information

• Product Name: 2,3-Dichloropyridine
• Synonyms: 2,3-DICHLOROPYRIDINE;2,3-dichloro-pyridin;2,3-Dichloropyridine147.99;2,3-Dichloropyridine,99%;2,3-DICHLOROPYRIDINE 2,3-DICHLOROPYRIDINE;2,3-dichloropydine;2,3-Dichloropyridine ,98%;3-Dichloropyridine
• CAS NO: 2402-77-9
• Molecular Formula: C₅H₃Cl₂N
• Molecular Weight: 147.99
• EINECS: 219-281-8
• Product Categories: blocks;Pyridines;Pyridine;Halides;Heterocycles;Pyridines, Pyrimidines, Purines and Pteredines;Pyridine series;Pyridines derivates;Chloropyridines;Halopyridines;Boronic Acid;C5Heterocyclic Building Blocks;Halogenated Heterocycles;Heterocyclic Building Blocks;Chlorinated heterocyclic series;alkyl chloride
• Mol File: 2402-77-9.mol
• Article Data: 52

Chemical Properties

• Melting Point: 64-67 °C(lit.)
• Boiling Point: 242.42°C (rough estimate)
• Flash Point: 87.5 °C
• Appearance: White to slightly beige/Crystalline Powder
• Density: 1.5159 (rough estimate)
• Vapor Pressure: 0.679mmHg at 25°C
• Refractive Index: 1.5500 (estimate)
• Storage Temp.: Inert atmosphere,Room Temperature
• PKA: -0.63±0.10(Predicted)
• Water Solubility: slightly soluble
• BRN: 109811
• CAS DataBase Reference: 2,3-Dichloropyridine(CAS DataBase Reference)
• NIST Chemistry Reference: 2,3-Dichloropyridine(2402-77-9)
• EPA Substance Registry System: 2,3-Dichloropyridine(2402-77-9)

Safety Data

• Hazard Codes: Xi,Xn
• Statements: 36/37/38-22
• Safety Statements: 26-36-37/39
• RIDADR: UN2811
• WGK Germany: 3
• RTECS: US8050000
• HazardClass: 6.1
• Hazardous Substances Data: 2402-77-9(Hazardous Substances Data)

Usage

Description

2,3-Dichloropyridine is an organic compound with the chemical formula C5H3Cl2N. It is a white to slightly beige crystalline powder that serves as a versatile reagent in the synthesis of various chemical compounds.

Uses

Used in Pharmaceutical Industry:
2,3-Dichloropyridine is used as a reagent for the preparation of substituted 3-(5-membered heterocycle-carboxamido)pyridine derivatives. These derivatives are utilized in the treatment of autoimmune and inflammatory diseases, making it a valuable component in the development of new medications for these conditions.
Used in Agricultural Industry:
In the agricultural sector, 2,3-Dichloropyridine is employed in the synthesis of novel anthranilic diamide insecticides with propargyl ether. These insecticides exhibit biological activity against various pests, contributing to more effective pest control strategies in agriculture.
Used in Chemical Research:
Due to its reactivity and structural properties, 2,3-Dichloropyridine is also used as a starting material or intermediate in various chemical research applications, allowing scientists to explore new compounds and reactions with potential industrial or commercial significance.

InChI:InChI=1/C5H3Cl2N/c6-4-2-1-3-8-5(4)7/h1-3H

Synthetic route

2,3,4,6-Tetrachloropyridine (14121-36-9) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With hydrogen; triethylamine; urea; citric acid In ethyl acetate at 50℃; under 7500.75 Torr; for 7h; Solvent; Temperature; Pressure; Reagent/catalyst; Autoclave;	98.1%

2,3,6-trichloropyridine (6515-09-9) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With carbonylhydridetris(triphenylphosphine)rhodium(I); hydrogen; triethylamine In methanol at 60℃; under 450045 Torr; Temperature; Solvent; Pressure; Autoclave;	98%
With methanol; palladium 10% on activated carbon; 3-p-menthene at 60℃; for 4h; Temperature; Reagent/catalyst;	95%
With hydrogen In methanol at 75℃; under 750.075 Torr; for 8h; Reagent/catalyst; Autoclave;	95.3%

2,6-dichloropyridine (2402-78-0) → 2,3-dichloro-pyridine (2402-77-9) + 2,6-difluoro pyridine (1513-65-1)

Conditions	Yield
In dimethyl sulfoxide	A 96.3% B n/a

2-chloro-3-aminopyridine (6298-19-7) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Stage #1: 2-chloro-3-aminopyridine With hydrogenchloride; sodium nitrite In water at 5 - 15℃; for 0.75h; Stage #2: With hydrogenchloride; aminosulfonic acid; copper(II) chloride dihydrate In water at 55 - 62℃; Product distribution / selectivity;	95%
With hydrogenchloride; thionyl chloride; nitric acid In water at 0 - 5℃;	91%
With hydrogenchloride; sodium nitrite In water at -5 - 40℃; for 1h; Sandmeyer Reaction; Cooling with ice; Inert atmosphere;	83%

2-hydroxy-3-chloropyridine (13466-35-8) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With phosphorus pentachloride In 1,2-dichloro-ethane at 60 - 65℃; for 10h; Reagent/catalyst; Temperature; Solvent;	94.9%
With phosphorus pentachloride In 1,2-dichloro-ethane at 60 - 65℃; for 10h; Reagent/catalyst; Temperature;	94.9%
With trichlorophosphate In 1,2-dichloro-ethane; N,N-dimethyl-formamide Reflux;	43g

2,3-Diaminopyridine (452-58-4) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With hydrogenchloride; copper dichloride; sodium nitrite In water at 20 - 45℃; for 5h; Reagent/catalyst; Large scale;	89.5%

2-chloro-3-hydroxypyridine (6636-78-8) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With trichlorophosphate In N,N-dimethyl-formamide at 0 - 30℃; for 9h; Reagent/catalyst;	88%
With chlorine In dichloromethane at 35 - 40℃; for 4h; Solvent; Temperature;	126 g
With sulfolane; phosphorus pentachloride; trichlorophosphate at 150℃; for 6h; Reagent/catalyst;

pyridine hydrochloride (628-13-7) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With pyridine; hydrogen In water at 40 - 60℃; under 2250.23 - 3750.38 Torr; Reagent/catalyst; Temperature; Pressure; Large scale;	86.6%
With pyridine; hydrogen In water at 40 - 60℃; under 2250.23 - 3750.38 Torr; Temperature; Pressure; Reagent/catalyst; Large scale;	86.6%

2-Chloro-3-nitropyridine (5470-18-8) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With Dichlorophenylphosphine In various solvent(s) at 170℃; for 5h;	81%
With sulfolane; phosphorus pentachloride; trichlorophosphate at 150℃; for 6h; Reagent/catalyst;

3-chloro-2-pyridinesulfonic acid → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Stage #1: 3-chloro-2-pyridinesulfonic acid With hydrogenchloride; water In water at 103℃; for 5h; Stage #2: With sodium chlorate for 5h; Temperature; Reflux;	80.3%

3-Chloropyridine (626-60-8) + acetyl hypofluorite (78948-09-1) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With dichloromethane	80%

3-chloropyridine-2-carboxylic acid (57266-69-0) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With tert-butylhypochlorite; dichloromethane; sodium hydrogencarbonate at 60℃; for 20h; Green chemistry;	80%
With tert-butylhypochlorite; sodium carbonate; sodium chloride In dichloromethane at 30℃; for 20h; Schlenk technique;	50%

2-Ethoxy-3-chloropyridine (177743-06-5) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With N,N-dimethyl-formamide; trichlorophosphate at 95℃; for 12h;	66%

2-Benzyloxy-3-chloro-pyridine → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With N,N-dimethyl-formamide; trichlorophosphate at 95℃; for 12h;	66%

Pyridin-Palladium(II)-chlorid-Komplex → 2-chloropyridine (109-09-1) + 2,3-dichloro-pyridine (2402-77-9) + 2,3,5-trichloropyridine (16063-70-0)

Conditions	Yield
With chlorine In cyclohexane at 75℃; for 1h;	A 9% B 62% C 4.5%

3-Chloropyridine (626-60-8) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Stage #1: 3-Chloropyridine With n-butyllithium In hexane at -60℃; for 1h; Stage #2: With hexachloroethane In tetrahydrofuran; hexane at -60 - 20℃;	60%
Multi-step reaction with 3 steps 1: 3-chloro-benzenecarboperoxoic acid / chloroform / 20 °C 2: 30 h / Reflux 3: trichlorophosphate / 6 h / 100 °C View Scheme

2-methoxy,3-chloropyridine (13472-84-9) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With trichlorophosphate In N,N-dimethyl-formamide at 95℃; for 12h;	59%
With N,N-dimethyl-formamide; trichlorophosphate at 95℃; for 12h;	59%

5,6-dichloronicotinic acid (41667-95-2) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
at 150℃; bei vorsichtiger Destillation unter vermindertem Druck;

3-chloropyridine-N-oxide (1851-22-5) → 2,5 dichloropyridine (16110-09-1) + 2,3-dichloro-pyridine (2402-77-9) + 3,4-dichloropyridine (55934-00-4)

Conditions	Yield
With trichlorophosphate at 110℃; for 2h; Yield given. Yields of byproduct given;

2-Chloro-pyridine-3-diazonium; chloride (121983-37-7) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With hydrogenchloride; copper(II) oxide In n-BuCl; water at 55 - 62℃; Product distribution / selectivity;
With hydrogenchloride; copper dichloride In n-Butyl chloride; water at 60℃; for 1.5h; Product distribution / selectivity;

2-chloro-3-aminopyridine (6298-19-7) → 2,3-dichloro-pyridine (2402-77-9) + 3,3'-dithiobis(2-chloropyridine) (69212-33-5) + 2-chloro-3-pyridinesulfonyl chloride (6684-06-6) + 2-chloropyridine-3-sulfonic acid (6602-56-8) + 3,3'-sulfonylbis(2-chloropyridine)

Conditions	Yield
Stage #1: 2-chloro-3-aminopyridine With hydrogenchloride; acetic acid; sodium nitrite In water at 0℃; Sandmeyer reaction; Stage #2: With sulfur dioxide; water; acetic acid; copper(l) chloride at 0℃; Sandmeyer reaction;

pyridin-3-ylamine (462-08-8) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Stage #1: pyridin-3-ylamine With hydrogenchloride; iron(III) chloride; chlorine; sodium nitrite In water at -8 - 20℃; Stage #2: With hydrogenchloride; copper(l) chloride In water at 60 - 70℃;
Multi-step reaction with 2 steps 1: iron(III) chloride; hydrogenchloride; chlorine / water / 25 °C 2: iron(III) chloride; sodium nitrite / water / 30 °C View Scheme
Stage #1: pyridin-3-ylamine With hydrogenchloride; dihydrogen peroxide In water at 5℃; for 2h; Stage #2: With sodium nitrite In water at -5℃; for 0.416667h; Stage #3: With copper(l) chloride In dichloromethane; water at 15 - 30℃; for 1.33333h;
Multi-step reaction with 2 steps 1: dihydrogen peroxide / 1 h / 5 - 15 °C 2: copper(l) chloride; sodium nitrite / water / 0.5 h / 33 - 38 °C View Scheme

2-Chloronicotinoyl chloride (49609-84-9) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With oxalyl dichloride; palladium 10% on activated carbon In chlorobenzene at 380 - 395℃; for 1h; Time; Reagent/catalyst; Temperature; Solvent; Concentration; Inert atmosphere;	43 %Spectr.

nicotinamide (98-92-0) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Multi-step reaction with 3 steps 1: sodium hydroxide; sodium hypochlorite / 2 h / 10 - 95 °C 2: iron(III) chloride; hydrogenchloride; chlorine / water / 25 °C 3: iron(III) chloride; sodium nitrite / water / 30 °C View Scheme
Multi-step reaction with 3 steps 1: sodium hypochlorite / water / 2.5 h / 0 - 100 °C 2: dihydrogen peroxide / 1 h / 5 - 15 °C 3: copper(l) chloride; sodium nitrite / water / 0.5 h / 33 - 38 °C View Scheme

2-acetyloxy-3-chloropyridine (98273-80-4) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With trichlorophosphate at 100℃; for 6h; Reagent/catalyst;

2,3,6-trichloropyridine (6515-09-9) → 3-Chloropyridine (626-60-8) + 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With dichloro(pentamethylcyclopentadienyl)rhodium (III) dimer; hydrogen; triethylamine In isopropyl alcohol at 85℃; under 3750.38 Torr; for 3h;

2,3,6-trichloropyridine (6515-09-9) → 2-chloropyridine (109-09-1) + 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
With Wilkinson's catalyst; hydrogen; triethylamine In isopropyl alcohol at 85℃; under 3750.38 Torr; for 1h;

pyridine (110-86-1) → 2,3-dichloro-pyridine (2402-77-9) + 2,3,5-trichloropyridine (16063-70-0)

Conditions	Yield
Stage #1: pyridine With iron(III) chloride; chlorine In tetrachloromethane Large scale; Stage #2: With palladium on activated charcoal In tetrachloromethane; ethanol at 80℃; under 750.075 Torr; Reagent/catalyst; Solvent; Pressure; Temperature; Large scale;	A 8 kg B 1840.8 kg

3-pyridyl acetate (17747-43-2) → 2,3-dichloro-pyridine (2402-77-9)

Conditions	Yield
Multi-step reaction with 3 steps 1: chlorine / dichloromethane; water / 4 h / 20 - 30 °C 2: water / dichloromethane / 2 h / 35 - 40 °C 3: chlorine / dichloromethane / 4 h / 35 - 40 °C View Scheme

2,3-dichloro-pyridine (2402-77-9) + bis(triphenylphosphine)nickel(II) chloride (14264-16-5, 53996-95-5, 62075-39-2, 39716-73-9) → [NiCl(ClC5H3N)(P(C6H5)3)]2 (680973-41-5)

Conditions	Yield
With Zn; azabis(isobutyronitrile) In tetrahydrofuran (Ar); stirring (25°C, 1 h); solvent removal, extracting (CH2Cl2), filtn., solvent removal, stirring (Et2O), filtn., recrystallization (CH2Cl2); elem. anal.;	99%

2,3-dichloro-pyridine (2402-77-9) + pyrrole (109-97-7) → 3-chloro-2-(1H-pyrrol-1-yl)pyridine (914457-19-5)

Conditions	Yield
Stage #1: pyrrole With sodium hydride In N,N-dimethyl-formamide at 0 - 20℃; for 0.5h; Stage #2: 2,3-dichloro-pyridine In N,N-dimethyl-formamide at 80℃; for 3h;	99%

2,3-dichloro-pyridine (2402-77-9) → (3-chloro-2-pyridyl)hydrazine (22841-92-5)

Conditions	Yield
With N-Methyldiethanolamine; hydrazine hydrate at 102 - 105℃; under 2250.23 - 3000.3 Torr; for 8h; Inert atmosphere; Autoclave; Large scale;	98.12%
With hydrazine hydrate In ethanol for 25h; Reflux;	97.6%
With hydrazine hydrate In ethanol for 25h; Reflux;	96%

benzoxazole (273-53-0) + 2,3-dichloro-pyridine (2402-77-9) → 2-(2-chloropyridin-3-yl)benzo[d]oxazole

Conditions	Yield
With copper(l) iodide; potassium phosphate tribasic heptahydrate; palladium diacetate; nixantphos In N,N-dimethyl-formamide at 120℃; for 12h; Inert atmosphere;	98%

2,3-dichloro-pyridine (2402-77-9) + tri(p-tolyl)bismuth (5142-75-6) → 3-chloro-2-(4-methylphenyl)pyridine (892482-36-9)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); caesium carbonate In N,N-dimethyl acetamide at 90℃; for 4h; Inert atmosphere; Schlenk technique; regioselective reaction;	97%

2,3-dichloro-pyridine (2402-77-9) → 2,3-dichloropyridine 1-oxide (53976-65-1)

Conditions	Yield
With trifluoromethylsulfonic anhydride; urea hydrogen peroxide adduct In dichloromethane at 10 - 20℃;	96%
With 3-chloro-benzenecarboperoxoic acid In dichloromethane at 0 - 30℃; for 32h; Inert atmosphere;	74%
With dihydrogen peroxide; acetic anhydride 1.)r.t., 5 h 2.)60-65 deg C, 30 h;
With urea hydrogen peroxide adduct; trifluoroacetic anhydride In dichloromethane at 0 - 20℃;	11 g

2,3-dichloro-pyridine (2402-77-9) + carbon dioxide (124-38-9) → 2,3-dichloroisonicotinic acid (184416-84-0)

Conditions	Yield
Stage #1: 2,3-dichloro-pyridine With n-butyllithium; diisopropylamine In tetrahydrofuran; hexane at -75℃; for 2h; Stage #2: carbon dioxide at -78℃;	96%
Stage #1: 2,3-dichloro-pyridine With n-butyllithium; diisopropylamine In tetrahydrofuran; hexane at -78 - -25℃; for 3h; Stage #2: carbon dioxide In tetrahydrofuran; hexane at 20℃; for 18h; Stage #3: With hydrogenchloride; water In tetrahydrofuran; diethyl ether; hexane at 0 - 20℃;	80%

2,3-dichloro-pyridine (2402-77-9) + 2,2,3,3-tetrafluoropropanol (76-37-9) → 3-chloro-2-(2,2,3,3-tetrafluoropropyl)pyridine (1355067-32-1)

Conditions	Yield
Stage #1: 2,2,3,3-tetrafluoropropanol With sodium hydride In tetrahydrofuran; mineral oil at 0 - 20℃; for 1h; Stage #2: 2,3-dichloro-pyridine In tetrahydrofuran; mineral oil for 16h; Reflux;	96%
Stage #1: 2,2,3,3-tetrafluoropropanol With sodium hydride In tetrahydrofuran; mineral oil at 0 - 20℃; for 1h; Stage #2: 2,3-dichloro-pyridine In tetrahydrofuran; mineral oil for 16h; Reflux;	96%

2,3-dichloro-pyridine (2402-77-9) + 2-(prop-2-yloxycarbonyl)-5-trfluoromethylphenylboronic acid (444993-18-4) + lithium hydroxide (1310-65-2) → 2-(3-chloro-pyridin-2-yl)-4-trifluoromethyl-benzoic acid (1423022-47-2)

Conditions	Yield
Stage #1: 2,3-dichloro-pyridine; 2-(prop-2-yloxycarbonyl)-5-trfluoromethylphenylboronic acid With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In 1,4-dioxane; water at 30 - 110℃; for 20h; Inert atmosphere; Stage #2: lithium hydroxide In 1,4-dioxane; water at 70℃;	96%

2,3-dichloro-pyridine (2402-77-9) + 3-bromo-4,5-dihydro-1H-pyrazole-5-carboxylic acid ethyl ester → 5-bromo-2-(3-chloro-pyridin-2-yl)-3,4-dihydro-2H-pyrazole-3-carboxylic acid ethyl ester (500011-91-6)

Conditions	Yield
With sodium ethanolate In ethanol at 83℃; for 3h;	94.9%

piperazine (110-85-0) + 2,3-dichloro-pyridine (2402-77-9) → 1-(3-chloro-2-pyridyl)piperazine (87394-55-6)

Conditions	Yield
In butan-1-ol for 3h; Reflux;	94%
In butan-1-ol for 18h; Reflux;	92%
In ethanol 1.) ice bath, 2.) room temperature;	90.8%

2,3-dichloro-pyridine (2402-77-9) + 2-(adamantan-1-yloxy)ethan-1-amine (25225-13-2) → N-[2-(1-adamantyloxy)ethyl]-3-chloropyridin-2-amine

Conditions	Yield
With 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; bis(dibenzylideneacetone)-palladium(0); sodium t-butanolate In 1,4-dioxane Reagent/catalyst; Solvent; Temperature; Inert atmosphere; Reflux;	94%

2-aminopyridine (504-29-0) + 2,3-dichloro-pyridine (2402-77-9) → 3-chloro-N-(pyridin-2-yl)pyridin-2-amine (138144-95-3)

Conditions	Yield
With potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; palladium diacetate In toluene for 18h; Heating;	93%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 180℃; for 0.5h; Buchwald-Hartwig amination; Inert atmosphere; Microwave irradiation; regioselective reaction;	81%
With palladium diacetate; triphenylphosphine; sodium t-butanolate In toluene at 120℃; for 17h; Inert atmosphere;	61.7%

2,3-dichloro-pyridine (2402-77-9) + 4-methoxy-aniline (104-94-9) → 3-chloro-N-(4-methoxyphenyl)pyridin-2-amine (370571-31-6)

Conditions	Yield
With potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; palladium diacetate In toluene for 18h; Heating;	93%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene for 18h; Buchwald-Hartwig reaction; Reflux; regioselective reaction;	93%
Stage #1: 2,3-dichloro-pyridine With palladium diacetate; triphenylphosphine; sodium t-butanolate In toluene under 20 Torr; for 0.166667h; Buchwald-Hartwig Coupling; Inert atmosphere; Stage #2: 4-methoxy-aniline In toluene at 100℃; for 16h; Buchwald-Hartwig Coupling; Inert atmosphere;	91%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 180℃; for 0.5h; Buchwald-Hartwig amination; Inert atmosphere; Microwave irradiation; regioselective reaction;	82%

2,3-dichloro-pyridine (2402-77-9) + 3,5-Dimethoxyaniline (10272-07-8) → C13H13ClN2O2 (1146547-65-0)

Conditions	Yield
Stage #1: 2,3-dichloro-pyridine With palladium diacetate; triphenylphosphine; sodium t-butanolate In toluene under 20 Torr; for 0.166667h; Buchwald-Hartwig Coupling; Inert atmosphere; Stage #2: 3.5-dimethoxyaniline In toluene at 100℃; for 16h; Buchwald-Hartwig Coupling; Inert atmosphere;	93%
Stage #1: 2,3-dichloro-pyridine; 3.5-dimethoxyaniline With palladium diacetate; triphenylphosphine; sodium t-butanolate In o-xylene at 120℃; for 3h; Inert atmosphere; Stage #2: With palladium diacetate; 1,8-diazabicyclo[5.4.0]undec-7-ene; tricyclohexylphosphine tetrafluoroborate In N,N-dimethyl acetamide; o-xylene at 145℃; for 16h; Inert atmosphere;	66%
With palladium diacetate; triphenylphosphine; sodium t-butanolate Inert atmosphere; Heating;

2,3-dichloro-pyridine (2402-77-9) + sodium 4-methylbenzenesulfinate (824-79-3) → 3-chloro-2-(toluene-4-sulfonyl)-pyridine (1258786-39-8)

Conditions	Yield
With hydrogenchloride; tetrabutyl-ammonium chloride In N,N-dimethyl acetamide; water at 100℃; for 24h;	93%

4-HYDROXYPIPERIDINE (5382-16-1) + 2,3-dichloro-pyridine (2402-77-9) → 1-(3-chloropyridin-2-yl)piperidin-4-ol (1250282-78-0)

Conditions	Yield
In dimethyl sulfoxide at 120℃;	93%
In N,N-dimethyl-formamide at 80 - 90℃; for 3h;	1.76 g

2,3-dichloro-pyridine (2402-77-9) + 3-bromo-4,5-dihydro-1H-pyrazole-5-carboxylic acid methyl ester → 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid methyl ester

Conditions	Yield
With sodium methylate In methanol at 80℃; for 3h;	92.7%

2,3-dichloro-pyridine (2402-77-9) + 4,4-ethylenedioxy-piperidine (177-11-7) → C12H15ClN2O2 (828265-97-0)

Conditions	Yield
With potassium carbonate In dimethyl sulfoxide at 150℃; for 16h;	92.5%
With triethylamine In ethanol at 160℃;
With N-ethyl-N,N-diisopropylamine In dimethyl sulfoxide at 125℃; for 12h;

2,3-dichloro-pyridine (2402-77-9) + tris(4-methoxyphenyl)bismuth (33397-21-6) → 3-chloro-2-(4-methoxyphenyl)pyridine

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); caesium carbonate In N,N-dimethyl acetamide at 90℃; for 4h; Inert atmosphere; Schlenk technique; regioselective reaction;	92%

2-Aminopyrazine (5049-61-6) + 2,3-dichloro-pyridine (2402-77-9) → (2-pyrazyl)(3-chloro-2-pyridyl)amine

Conditions	Yield
With potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; palladium diacetate In toluene for 18h; Heating;	91%

2,3-dichloro-pyridine (2402-77-9) + 2-methoxy-phenylamine (90-04-0) → 3-chloro-N-(2-methoxyphenyl)pyridin-2-amine (1005499-19-3)

Conditions	Yield
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene for 18h; Buchwald-Hartwig reaction; Reflux; regioselective reaction;	91%
Stage #1: 2,3-dichloro-pyridine With palladium diacetate; triphenylphosphine; sodium t-butanolate In toluene under 20 Torr; for 0.166667h; Buchwald-Hartwig Coupling; Inert atmosphere; Stage #2: 2-methoxy-phenylamine In toluene at 100℃; for 16h; Buchwald-Hartwig Coupling; Inert atmosphere;	82%
With potassium carbonate; palladium diacetate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 120℃; for 2h;	81%

2,3-dichloro-pyridine (2402-77-9) + benzylamine (100-46-9) → N-benzyl-3-chloro-2-pyridinamine (1042512-03-7)

Conditions	Yield
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 130℃; for 16h; Inert atmosphere;	91%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 130℃; for 16h; Buchwald-Hartwig Coupling; Inert atmosphere;	91%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 130℃; for 16h; Inert atmosphere;	91%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 130℃; for 16h; Inert atmosphere;	90%
With palladium diacetate; potassium carbonate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 180℃; for 0.5h; Buchwald-Hartwig amination; Inert atmosphere; Microwave irradiation; regioselective reaction;	52%

2,3-dichloro-pyridine (2402-77-9) + 4-tert-butylphenylboronic acid (123324-71-0) → C15H16ClN

Conditions	Yield
With palladium diacetate; potassium carbonate; nixantphos In tetrahydrofuran; water at 20℃; for 6h; Suzuki-Miyaura Coupling;	91%

2,3-dichloro-pyridine (2402-77-9) + benzyl(bromo)zinc (62673-31-8) → 2-benzyl-3-chloropyridine

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran at 70℃; for 18h; Inert atmosphere;	91%

Upstream product

• 5470-18-8 2-Chloro-3-nitropyridine 
• 626-60-8 3-Chloropyridine 
• 6636-78-8 2-chloro-3-hydroxypyridine 
• 462-08-8 pyridin-3-ylamine 
• 120-92-3 cyclopentanone 
• 45506-41-0 2-hydroxy-piperidine 
• 675-20-7 piperidin-2-one 
• 1192-28-5 Cyclopentanone oxime 
• 14121-36-9 2,3,4,6-Tetrachloropyridine 
• 16867-04-2 dihydroxypyridine 
• 6332-56-5 2-hydroxy-3-nitropyridine 
• 57266-69-0 3-chloropyridine-2-carboxylic acid 
• 74885-85-1 3-(Formyloxy)pyridin 
• 109-00-2 3-HYDROXYPYRIDINE 

Downstream Products

• 100707-68-4 2-butoxy-3-chloro-pyridine 
• 85344-73-6 1-Azathianthrene 
• 170808-74-9 3-Chloro-2,3'-bipyridine 
• 626-60-8 3-Chloropyridine 
• 116383-98-3 3-chloro-2-(methoxycarbonyl)pyridine 
• 370571-31-6 3-chloro-N-(4-methoxyphenyl)pyridin-2-amine 
• 370571-30-5 3-chloro-N-(4-nitrophenyl)pyridin-2-amine 
• 483324-02-3 3-chloro-2-(4-methoxyphenyl)pyridine 
• 96424-68-9 2-bromo-3-chloropyridine 
• 77332-89-9 2-iodo-3-pyridyl chloride 
• 859826-08-7 [7-(3-Chloro-pyridin-2-yl)-2-methylsulfanyl-5,6,7,8-tetrahydro-pyrido[3,4-d]pyrimidin-4-yl]-(4-trifluoromethyl-phenyl)-amine 
• 859826-26-9 N-(4-tert-butylphenyl)-7-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-2-(methylthio)pyrido[3,4-d]pyrimidin-4-amine 
• 481049-31-4 8-chloro-2-(4-fluorophenyl)imidazo[1,2-a]pyridine 
• 481049-32-5 8-chloro-2-(4-fluorophenyl)imidazo[1,2-a]pyridine-3-carbaldehyde 

Relevant articles and documents

A PROCESS FOR THE PREPARATION OF SUBSTITUTED PYRIDINE COMPOUNDS AND INTERMEDIATES THEREOF

The present invention discloses a process for the preparation of substituted pyridine compounds of formula (I), comprises a step in which vinylogous nitriles of formula (II), are obtained from substituted α,β-unsaturated nitrile compounds of formula (III), and a further step of converting the vinylogous nitrile compounds of formula (II) into substituted pyridines of formula (I); wherein R1, R2, R3, R4 and LG are as defined in the description.

Industrial synthesis method of 2, 3-dichloropyridine

The invention discloses an industrial synthesis method of 2, 3-dichloropyridine, which comprises the following steps of S1, taking anhydrous acetaldehyde as a raw material, and carrying out dehydration reaction with benzylamine to synthesize N-substituted enamine, S2, reacting the N-substituted enamine with an acylating agent in the presence of an acid-binding agent and a solvent to synthesize N-substituted-N-(1-vinyl)-chloroacetamide, S3, carrying out cyclization reaction on the N-substituted-N-(1-vinyl)-chloroacetamide and a vilsmeier reagent in the presence of a solvent, so as to generate N-substituted-2, 3-dichloropyridine pyridinium chloride salt, S4, enabling the N-substituted-2, 3-dichloropyridine pyridinium chloride salt to be heated and then subjected to a pyrolytic reaction, and producing a 2, 3-dichloropyridine crude product, and S5, purifying the 2, 3-dichloropyridine crude product to obtain a 2, 3-dichloropyridine finished product. The method has the advantages of mild reaction conditions, wide and easy-to-purchase reaction raw materials, no focused dangerous process in the reaction process, high reaction yield, safe and easy-to-control process, less three wastes generated by the process, and suitableness for expanded production.

Preparation method of 2,3-dichloropyridine

The invention provides a preparation method of 2,3-dichloropyridine. The preparation method comprises the steps: uniformly mixing 3-chloropyridine and a solvent, adding a catalyst, adding chlorosulfonic acid, carrying out sulfonation reaction, carrying out post-reaction treatment to obtain an intermediate, and chlorinating the intermediate under the actions of hydrochloric acid and sodium chlorateto obtain 2,3-dichloropyridine. The preparation method has the advantages of short reaction steps, simple operation, few side reactions, few three wastes in the production process, low equipment requirements, no need of high equipment investment, and high product yield.