626-05-1

Basic information

• Product Name: 2,6-Dibromopyridine
• Synonyms: 2,6-DIBROMOPYRIDINE;2,6-dibromo-pyridin;2,6-Dibromopyridine,98%;Pyridine, 2,6-dibromo-;2,6-DibroMopyridine, 98% 25GR;2,4-dibroMo-6-nitropyridine
• CAS NO: 626-05-1
• Molecular Formula: C₅H₃Br₂N
• Molecular Weight: 236.89
• EINECS: 210-926-9
• Product Categories: Pyridine;Pyridine Series;Pyridines, Pyrimidines, Purines and Pteredines;Pyridines;Bromopyridines;Halopyridines;C5Heterocyclic Building Blocks;Halogenated Heterocycles;Heterocyclic Building Blocks;Building Blocks;C5;Chemical Synthesis;Halogenated Heterocycles;Heterocyclic Building Blocks;alkyl bromide
• Mol File: 626-05-1.mol
• Article Data: 7

Chemical Properties

• Melting Point: 117-119 °C(lit.)
• Boiling Point: 255°C
• Flash Point: 213 °C
• Appearance: White to gray or buff/Crystalline Powder
• Density: 2.0383 (rough estimate)
• Vapor Pressure: 0.0255mmHg at 25°C
• Refractive Index: 1.5800 (estimate)
• Storage Temp.: Store below +30°C.
• Solubility: Chloroform (Slightly), Methanol (Slightly)
• PKA: -3.65±0.10(Predicted)
• Water Solubility: insoluble
• BRN: 108922
• CAS DataBase Reference: 2,6-Dibromopyridine(CAS DataBase Reference)
• NIST Chemistry Reference: 2,6-Dibromopyridine(626-05-1)
• EPA Substance Registry System: 2,6-Dibromopyridine(626-05-1)

Safety Data

• Hazard Codes: Xi,T,T+
• Statements: 36/37/38-25-20/21-52-28-52/53-36/38
• Safety Statements: 26-37/39-45-36/37/39-36-36/37-28-61
• RIDADR: 2811
• WGK Germany: 3
• RTECS: US7883000
• HazardClass: 6.1
• PackingGroup: II
• Hazardous Substances Data: 626-05-1(Hazardous Substances Data)

Usage

Chemical Properties

White to light yellow crystalline powder

Uses

2,6-Dibromopyridine is used as a tridentate chelating ligand and in the formation of macrocycles containing the terpyridine moiety. It is also used to produce 6-bromo-2-methoxypyridine.

Purification Methods

Purify 2,6-dibromopyridine by steam distillation, then recrystallise it twice from EtOH. It does not form an HgCl2 salt. [den Hertog & Wibaut Recl Trav Chim Pays Bas 51 381 1932, Beilstein 20/5 V 435.]

InChI:InChI=1/C5H3Br2N/c6-4-2-1-3-5(7)8-4/h1-3H

Synthetic route

2,6-dibromopyridin N-oxide (25373-69-7) → 2,6-Dibromopyridine (626-05-1)

pyridine N-oxide (694-59-7) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
With carbon tetrabromide; lithium tert-butoxide In m-xylene at 100℃; for 1h; Inert atmosphere;	30%

pyridine (110-86-1) → 2-bromo-pyridine (109-04-6) + 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
With bromine at 500℃; Leiten ueber Bimsstein;
With bromine at 500℃; Leiten ueber Glas;

2,6-dichloropyridine (2402-78-0) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
With acetic acid

2-bromo-pyridine (109-04-6) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
With bromine at 300℃; Leiten ueber mit Kupfer(I)-bromid impraegnierten Bimsstein;

silver salt of/the/ 2.6-dibromo-isonicotinic acid → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
at 226℃;

2,6-dibromo-3-aminopyridine (39856-57-0) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
With ethanol; sulfuric acid anschliessend Behandeln mit wss. Natriumnitrit-Loesung;

pyridin-3-ylamine (462-08-8) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: methanol; bromine 2: ethanol; concentrated sulfuric acid / anschliessend Behandeln mit wss. Natriumnitrit-Loesung View Scheme

pyridine (110-86-1) + bromine (7726-95-6) + pumice stone → 2-bromo-pyridine (109-04-6) + 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
at 500℃;

6-bromo-1-methyl-1,2-dihydropyridin-2-one (873383-11-0) + phosphorus tribromide (7789-60-8) + phosphorus pentabromide (7789-69-7) → 2,6-Dibromopyridine (626-05-1)

Conditions	Yield
at 190℃;

2-bromo-pyridine (109-04-6) + bromine (7726-95-6) + copper (I)-bromide → 2,6-Dibromopyridine (626-05-1) + pentabromopyridine (2402-94-0)

Conditions	Yield
at 300℃;

2,6-Dibromopyridine (626-05-1) + carbon monoxide (201230-82-2) + 4-chloro-aniline (106-47-8) → N,N'-bis(4'-chlorophenyl)pyridine-2,6-dicarboxamide (126230-11-3)

Conditions	Yield
With triethylamine; tetrakis(triphenylphosphine) palladium(0) In toluene at 100℃; under 2574.3 Torr; for 8h;	100%

2,6-Dibromopyridine (626-05-1) + trimethylsilylacetylene (1066-54-2) → 2,6-bis(2-(trimethylsilyl)ethynyl)pyridine (75867-44-6)

Conditions	Yield
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine In toluene at 20℃; Sonogashira Cross-Coupling;	100%
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine In tetrahydrofuran at 50℃; for 6h; Inert atmosphere;	98%
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); N-ethyl-N,N-diisopropylamine In toluene for 90h; Sonogashira Cross-Coupling; Inert atmosphere; Darkness;	98%

2,6-Dibromopyridine (626-05-1) → 2-bromo-pyridine (109-04-6)

Conditions	Yield
With n-butyllithium; butyl magnesium bromide In toluene at -10℃;	100%
With n-butyllithium; isopropyl alcohol In hexane; dichloromethane 1.) -78 deg C, 1 h, 2.) -78 deg C, 30, min; warm to room temperature;	90%
With n-butyllithium; formaldehyd In tetrahydrofuran at -70 - -40℃;	90%

2,6-Dibromopyridine (626-05-1) + benzylamine (100-46-9) → 2-N-benzylamino-6-bromopyridine (427900-17-2)

Conditions	Yield
at 150℃; for 0.5h; Microwave irradiation;	100%
With potassium fluoride on basic alumina; palladium diacetate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl at 90 - 100℃; for 8h;	90%
at 150℃; for 5h; Autoclave;	48%

2,6-Dibromopyridine (626-05-1) + 4-chlorobenzylamine (104-86-9) → (6-bromopyridin-2-yl)(4-chlorobenzyl)amine (866546-12-5)

Conditions	Yield
at 150℃; for 0.5h; Neat (no solvent); Microwave irradiation;	100%

2,6-Dibromopyridine (626-05-1) + pentanal (110-62-3) → 1-(6-bromo-2-pyridinyl)-1-pentanol (638214-52-5)

Conditions	Yield
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; hexanes at -78℃; for 1h; Stage #2: pentanal In tetrahydrofuran; hexanes at -78℃; for 0.266667h;	100%

2,6-Dibromopyridine (626-05-1) + dinaphthalen-1-ylzinc → 2,6-di(naphthalen-1-yl)pyridine (1256169-52-4)

Conditions	Yield
With dichloro{bis[1-(dicyclohexylphosphanyl)piperidine]}palladium(II) In tetrahydrofuran; 1-methyl-pyrrolidin-2-one at 100℃; for 0.5h; Negishi cross-coupling reaction; In air;	100%

2,6-Dibromopyridine (626-05-1) + benzyl alcohol (100-51-6) → 2-(benzyloxy)-6-bromopyridine (117068-71-0)

Conditions	Yield
With potassium hydroxide; 18-crown-6 ether In toluene for 1h; Heating;	99.9%
Stage #1: benzyl alcohol With sodium hydride In tetrahydrofuran for 0.5h; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran at 20℃; for 18h;	90%
With sodium hydride In N,N-dimethyl-formamide at 0 - 100℃; for 18h;	79%

2,6-Dibromopyridine (626-05-1) + acetonitrile (75-05-8) → 2-(6-bromopyridin-2-yl)acetonitrile (112575-11-8)

Conditions	Yield
Stage #1: acetonitrile With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.5h; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran; hexane at -78 - 20℃; for 1.25h;	99%
Stage #1: acetonitrile With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.75h; Metallation; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran; hexane at -78 - 20℃; for 2.5h; Alkylation;	91%
With n-butyllithium 1.) hexane, THF,-70 deg C, 1 h, 2.) -70 deg C,1 h; Yield given. Multistep reaction;
Stage #1: acetonitrile With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.5h; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran; hexane at -78 - 20℃; for 1.5h;
Stage #1: acetonitrile With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.5h; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran; hexane at -78℃; for 0.75h;

2,6-Dibromopyridine (626-05-1) → 2-bromo-6-deuteropyridine (74126-93-5)

Conditions	Yield
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; hexane at -75℃; for 0.25h; Inert atmosphere; Stage #2: With deuteromethanol In tetrahydrofuran; hexane at -75℃; for 1.01667h;	99%
Stage #1: 2,6-Dibromopyridine With isopropylmagnesium chloride In tetrahydrofuran at 20℃; for 2h; Substitution; Stage #2: With water-d2 In tetrahydrofuran at 20℃; for 18h; Substitution;	95%
With n-butyllithium; Isopropanol-d1 In hexane; dichloromethane 1.) -78 deg C, 1 h, 2.) -78 deg C, 30, min; warm to room temperature;	86%
Stage #1: 2,6-Dibromopyridine In tetrahydrofuran at 20℃; for 1h; Stage #2: With water-d2 In tetrahydrofuran for 0.5h;

2,6-Dibromopyridine (626-05-1) + tris((2-phenyl)ethynyl)indium (250643-76-6) → 2,6-bis(2-phenylethynyl)pyridine (83965-72-4)

Conditions	Yield
(1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride In tetrahydrofuran Heating;	99%

2,6-Dibromopyridine (626-05-1) + phenylboronic acid (98-80-6) → 2,6-diphenylpyridine (3558-69-8)

Conditions	Yield
With C37H28N8O*2Cl(1-)*Pd(2+); potassium carbonate In ethanol at 70℃; for 2h; Suzuki-Miyaura Coupling;	99%
With potassium phosphate tribasic trihydrate; trans-[(2-mesitylpy)2PdCl2] In methanol; water at 80℃; for 1h; Suzuki-Miyaura Coupling;	99%
With {2,6-bis[(di-1-piperidinylphosphino)amino]phenyl}palladium(II) chloride; potassium carbonate In 1,4-dioxane; water; butan-1-ol at 100℃; for 2h; Suzuki-Miyaura reaction;	96%

2,6-Dibromopyridine (626-05-1) + 2-Methylphenylboronic acid (16419-60-6) → 2,6-di(2-methylphenyl)pyridine

Conditions	Yield
With potassium phosphate tribasic trihydrate; trans-[(2-mesitylpy)2PdCl2] In methanol; water at 80℃; for 1h; Catalytic behavior; Solvent; Time; Reagent/catalyst; Suzuki-Miyaura Coupling;	99%
With tris(dibenzylideneacetone)dipalladium (0); tri-tert-butyl phosphine In tetrahydrofuran for 16h; Heating;	65%
With tri-tert-butyl phosphine; tris-(dibenzylideneacetone)dipalladium(0) In tetrahydrofuran	65%
With potassium phosphate; dichloro{bis[1-(dicyclohexylphosphanyl)piperidine]}palladium(II) In toluene at 80℃; for 4h; Suzuki-Miyaura cross-coupling reaction; Air;	64%

2,6-Dibromopyridine (626-05-1) + phenylacetylene (536-74-3) → 2,6-bis(2-phenylethynyl)pyridine (83965-72-4)

Conditions	Yield
With C19H16ClNPdS; potassium carbonate In N,N-dimethyl-formamide at 110℃; for 24h; Reagent/catalyst; Sonogashira Cross-Coupling;	99%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In N,N-dimethyl-formamide at 80℃; Inert atmosphere;	96%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In N,N-dimethyl-formamide at 80℃; Inert atmosphere;	96%

2,6-Dibromopyridine (626-05-1) + 3,4,5-Trimethoxyaniline (24313-88-0) → 6-bromo-N-(3,4,5-trimethoxyphenyl)pyridin-2-amine (1130556-36-3)

Conditions	Yield
With potassium hexamethylsilazane In 1,4-dioxane at 20℃; for 1h;	99%
With potassium phosphate In 1,4-dioxane at 25℃; for 0.333333h; metal-free Buchwald-Hartwig amination; Inert atmosphere;	98%

2,6-Dibromopyridine (626-05-1) + N-methylaniline (100-61-8) → N,N'-dimethyl-N,N'-diphenylpyridine-2,6-diamine (1130556-33-0)

Conditions	Yield
With potassium hexamethylsilazane In 1,4-dioxane at 100℃; for 0.5h; metal-free Buchwald-Hartwig amination; Inert atmosphere;	99%

2,6-Dibromopyridine (626-05-1) + 4-(ethoxycarbonyl)phenylzinc iodide (131379-16-3) → diethyl 4,4'-pyridine-2,6-diyldibenzoate (1256169-65-9)

Conditions	Yield
With dichloro{bis[1-(dicyclohexylphosphanyl)piperidine]}palladium(II) In tetrahydrofuran; 1-methyl-pyrrolidin-2-one at 100℃; for 0.5h; Negishi cross-coupling reaction; In air;	99%

2,6-Dibromopyridine (626-05-1) + N-ethyl-N-phenylamine (103-69-5) → 6-bromo-N-ethyl-N-phenylpyridin-2-amine (1309609-43-5)

Conditions	Yield
With potassium hexamethylsilazane In 1,4-dioxane at 20℃; for 0.25h;	99%

2,6-Dibromopyridine (626-05-1) + 4-methylphenylboronic acid (5720-05-8) → 2,6-di-p-tolylpyridine (14435-88-2)

Conditions	Yield
With potassium phosphate tribasic trihydrate; trans-[(2-mesitylpy)2PdCl2] In methanol; water at 80℃; for 1h; Suzuki-Miyaura Coupling;	99%
With [Pd(Cl)κ2-S,N-C6H4CS=N-(4-Py)(PPh3)]; potassium carbonate In toluene at 80℃; for 5h; Suzuki coupling;	82%

2,6-Dibromopyridine (626-05-1) + 4-((tert-butyldimethylsilyl)oxy)-N,N,2,2-tetramethylbutanamide → 1-(6-bromopyridin-2-yl)-4-((tert-butyldimethylsilyl)oxy)-2,2-dimethylbutan-1-one

Conditions	Yield
Stage #1: 4-((tert-butyldimethylsilyl)oxy)-N,N,2,2-tetramethylbutanamide With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.5h; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran; hexane at -78 - 20℃; for 1h;	99%

piperidine (110-89-4) + 2,6-Dibromopyridine (626-05-1) → 2-bromo-6-(piperidin-1-yl)pyridine (24255-97-8)

Conditions	Yield
With potassium phosphate In 1,4-dioxane at 100℃; for 7h;	98%
With copper(l) iodide; potassium carbonate at 50℃; for 1h;	88%
With potassium phosphate In 1,4-dioxane at 105℃; for 10h; Inert atmosphere;	88%

2,6-Dibromopyridine (626-05-1) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 2-bromo-6-(hydroxymethyl)pyridine (33674-96-3)

Conditions	Yield
Stage #1: 2,6-Dibromopyridine; N,N-dimethyl-formamide With n-butyllithium Stage #2: With sodium tetrahydroborate	98%
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; hexane at -70℃; for 0.25h; Inert atmosphere; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; hexane at -78℃; for 0.25h; Further stages;	92%
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; light petroleum at -78℃; for 3.16667h; Inert atmosphere; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; light petroleum at -78℃; Inert atmosphere; Stage #3: With sodium tetrahydroborate In tetrahydrofuran; methanol; light petroleum; acetic acid at 20℃; Inert atmosphere;	82%

2,6-Dibromopyridine (626-05-1) + (1R)-fenchone (7787-20-4) → (1R,2R,4S)-2-(6-bromopyridine-2-yl)-1,3,3-trimethylbicyclo[2.2.1]heptan-2-ol (256428-16-7)

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane at -78℃; diastereoselective reaction;	98%
Stage #1: 2,6-Dibromopyridine With n-butyllithium In diethyl ether; hexane at -78℃; for 0.5h; Stage #2: (1R)-fenchone In diethyl ether; hexane Further stages.;	90%
Stage #1: 2,6-Dibromopyridine With n-butyllithium In diethyl ether; hexane at -78 - -45℃; for 0.25h; Metallation; Stage #2: (1R)-fenchone In diethyl ether; hexane at -78 - 20℃; for 3.5h; Addition;	48%

2,6-Dibromopyridine (626-05-1) + 4-methoxy-2,6-dimethylphenylboronic acid (361543-99-9) → 2,6-bis-(4-methoxy-2,6-dimethyl-phenyl)-isonicotinic acid methyl ester

Conditions	Yield
With tri-tert-butyl phosphine; tris-(dibenzylideneacetone)dipalladium(0) In tetrahydrofuran	98%

2,6-Dibromopyridine (626-05-1) + C9H15N3 (155511-82-3) → C14H17BrN4

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene In DMF (N,N-dimethyl-formamide) at 100℃; for 9h;	98%

2,6-Dibromopyridine (626-05-1) + acetone (67-64-1) → 2-(6-bromopyridin-2- yl)propan-2-ol (638218-78-7)

Conditions	Yield
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; hexane at -76 - -60℃; Stage #2: acetone In tetrahydrofuran; hexane at 20℃; Cooling with dry ice; Stage #3: With ammonium chloride In tetrahydrofuran; hexane; water	98%
With n-butyllithium In tetrahydrofuran; hexane at -76 - 20℃; for 1.25h; Cooling with ice;	94.3%
Stage #1: 2,6-Dibromopyridine With n-butyllithium In tetrahydrofuran; hexane at -76℃; for 0.75h; Cooling with acetone-dry ice; Stage #2: acetone In tetrahydrofuran; hexane at 20℃; for 1.25h; Cooling with acetone-dry ice;	94%

2,6-Dibromopyridine (626-05-1) + 2,6-diisopropylbenzenamine (24544-04-5) → N-[2,6-bis(1-methylethyl)phenyl]-6-bromopyridin-2-amine (1127647-91-9)

Conditions	Yield
With potassium phosphate In 1,4-dioxane at 25℃; for 0.333333h; metal-free Buchwald-Hartwig amination; Inert atmosphere;	98%
With potassium hexamethylsilazane In 1,4-dioxane at 20℃; for 1h;	78%
With 2,2,6,6-tetramethyl-piperidine at 230℃; for 6h; Sealed tube;	20%

2,6-Dibromopyridine (626-05-1) + N-methylaniline (100-61-8) → 6-bromo-N-methyl-N-phenylpyridin-2-amine (25194-53-0)

Conditions	Yield
With potassium phosphate In 1,4-dioxane at 25℃; for 0.333333h; metal-free Buchwald-Hartwig amination; Inert atmosphere;	98%
With potassium hexamethylsilazane In 1,4-dioxane at 20℃; for 0.5h;	98%

2,6-Dibromopyridine (626-05-1) + 2-(methylamino)-6-bromopyridine (89026-79-9) → N-methyl-bis(6-bromopyridin-2-yl)amine (1032745-39-3)

Conditions	Yield
Stage #1: 2-bromo-6-(methylamino)pyridine With sodium hydride In tetrahydrofuran at 20℃; Reflux; Stage #2: 2,6-Dibromopyridine In tetrahydrofuran for 6h; Reflux;	98%

Upstream product

• 110-86-1 pyridine 
• 109-04-6 2-bromo-pyridine 
• 39856-57-0 2,6-dibromo-3-aminopyridine 
• 873383-11-0 6-bromo-1-methyl-1,2-dihydropyridin-2-one 
• 7789-60-8 phosphorus tribromide 
• 7789-69-7 phosphorus pentabromide 
• 7726-95-6 bromine 
• 694-59-7 pyridine N-oxide 
• 2402-78-0 2,6-dichloropyridine 
• 462-08-8 pyridin-3-ylamine 
• 25373-69-7 2,6-dibromopyridin N-oxide 

Downstream Products

• 24255-97-8 2-bromo-6-(piperidin-1-yl)pyridine 
• 49669-22-9 6,6'-Dibromo-2,2'-bipyridine 
• 161584-87-8 Bis(6-bromo-2-pyridyl)<4-((tert-butyldimethylsilyl)oxy)phenyl>methanol 
• 100366-66-3 6,6-dibromo-2,2':6',2-terpyridine 
• 49669-16-1 tris<2-(6-bromopyridyl)>phosphine 
• 130897-00-6 6-bromo-6′-methyl-2,2′-bipyridine 
• 33777-92-3 6,6-dimethyl-2,2':6',2-terpyridine 
• 35299-71-9 2,6-bis(thiophen-2-yl)pyridine 
• 220196-07-6 2-bromo-6-(2'-thienyl)pyridine 
• 21190-88-5 6-bromopyridine-2-carboxylic acid ethyl ester 
• 214465-03-9 2,6-bis-(3-(2,4,6-trimethylphenyl)pyrazol-1-yl)pyridine 
• 41727-17-7 pyridine-2,6-dicarboxylic acid dibutyl ester 
• 251640-60-5 N,N'-bis[4-(methoxymethoxy)benzoyl]-2,6-bis[(6-aminopyrid-2-yl)ethynyl]pyridine 
• 2402-92-8 2,3,6-tribromopyridine 

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