14162-95-9

Basic information

• Product Name: 4-Bromo-2,2''-bipyridine
• Synonyms: 4-Bromo-2,2''-bipyridine;4-BroMo-2,2'-bipyridine 97%;4-broMo-2-(pyridin-2-yl)pyridine;2,2'-Bipyridine,4-bromo-;4-Bromo-2,2'-bipyridyl
• CAS NO: 14162-95-9
• Molecular Formula: C₁₀H₇BrN₂
• Molecular Weight: 235.08
• Product Categories: pharmacetical
• Mol File: 14162-95-9.mol
• Article Data: 21

Chemical Properties

• Melting Point: 52 °C
• Boiling Point: 325.163 °C at 760 mmHg
• Flash Point: 150.454 °C
• Appearance: /
• Density: 1.493
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• PKA: 3.70±0.22(Predicted)
• CAS DataBase Reference: 4-Bromo-2,2''-bipyridine(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Bromo-2,2''-bipyridine(14162-95-9)
• EPA Substance Registry System: 4-Bromo-2,2''-bipyridine(14162-95-9)

Safety Data

• Hazardous Substances Data: 14162-95-9(Hazardous Substances Data)

Usage

Uses

4-bromo-2,2'-bipyridine is a useful research chemical.

Synthetic route

4-bromo-2,2’-bipyridine N-oxide (14163-03-2) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With phosphorus tribromide In chloroform at 0 - 60℃; for 2h; Inert atmosphere;	99%
With phosphorus tribromide In chloroform at 0℃; for 5h; Inert atmosphere; Reflux;	98.7%
With phosphorus tribromide In dichloromethane for 4h; Inert atmosphere; Reflux;	94%

4-nitro-2,2'-bipyridine N-oxide (14163-00-9) → 4-bromo-2,2'-bipyridyl (14162-95-9) + 4-bromo-2,2’-bipyridine N-oxide (14163-03-2)

Conditions	Yield
With Acetyl bromide; acetic acid for 4h; Inert atmosphere; Reflux;	A 14.6% B 80.3%

4-nitro-2,2'-bipyridine N-oxide (14163-00-9) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With Acetyl bromide; phosphorus tribromide; acetic acid In chloroform	75%
With Acetyl bromide; acetic acid at 130℃; for 2h; Microwave irradiation;	75%
With Acetyl bromide; phosphorus tribromide at 40℃; for 1.25h; Reflux;	56%

2,2'-bipyridyl N-oxide (33421-43-1) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With Acetyl bromide In acetic acid for 24h; Inert atmosphere; Reflux;	68%
Multi-step reaction with 3 steps 1: 49 percent / HNO3; H2SO4 / 31 h / 100 °C 2: acetyl bromide 3: PBr3 View Scheme
Multi-step reaction with 2 steps 1: fuming HNO3, conc. H2SO4 / 3 h / 100 °C 2: 36 percent / AcBr, PPh3 / 2 h / Heating View Scheme

4-bromo-2,2′-bipyridine-1,1′-dioxide (249644-59-5) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With phosphorus tribromide In chloroform for 1.25h; deoxygenation; Heating;	60%

4-tributylstannyl-<2,2'>-bipyridine → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With bromine In chloroform at -60℃;	57%

3-(pyridin-2-yl)-1,2,4-triazine (30091-53-3) + tributylethynyltin (994-89-8) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
With bromine 1.) 1,2-dichlorobenzene, 180 deg C, 16 h; 2.) CHCl3, -60 deg C; Yield given. Multistep reaction;

[2,2]bipyridinyl (366-18-7) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
Multi-step reaction with 4 steps 1: 13.48 g / magnesium monoperoxyphthalate / ethanol / 5 h / Heating 2: 49 percent / HNO3; H2SO4 / 31 h / 100 °C 3: acetyl bromide 4: PBr3 View Scheme
Multi-step reaction with 3 steps 1: aq. H2O2, AcOH / 12 h / 60 °C 2: fuming HNO3, conc. H2SO4 / 3 h / 100 °C 3: 36 percent / AcBr, PPh3 / 2 h / Heating View Scheme
With hydrogen bromide; dihydrogen peroxide In methanol at 20℃; for 20h;

[2,2']bipyridinyl 1,1'-dioxide (7275-43-6) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
Multi-step reaction with 3 steps 1: 16 percent / KNO3; H2SO4 / 24 h / 100 °C 2: 64 percent / CH3COBr; glacial AcOH / 2 h / Heating 3: 60 percent / PBr3 / CHCl3 / 1.25 h / Heating View Scheme

4-nitro-2,2′-bipyridine N-oxide (14163-01-0) → 4-bromo-2,2'-bipyridyl (14162-95-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: 64 percent / CH3COBr; glacial AcOH / 2 h / Heating 2: 60 percent / PBr3 / CHCl3 / 1.25 h / Heating View Scheme

potassium hexafluorophosphate (17084-13-8) + {bis(2-(2'-phenylato)pyridine)Cliridium(III)}2 + 4-bromo-2,2'-bipyridyl (14162-95-9) → C32H23BrIrN4(1+)*F6P(1-)

Conditions	Yield
Stage #1: {bis(2-(2'-phenylato)pyridine)Cliridium(III)}2; 4-bromo-2,2'-bipyridyl In methanol; dichloromethane for 1.5h; Reflux; Stage #2: potassium hexafluorophosphate In water; acetonitrile	98%

4-bromo-2,2'-bipyridyl (14162-95-9) + trimethylsilylacetylene (1066-54-2) → 4-<2-(trimethylsilyl)-1-ethynyl>-2,2'-bipyridine (146548-23-4)

Conditions	Yield
With diisopropylamine; tetrakis(triphenylphosphine) palladium(0)	97%
With tetrakis(triphenylphosphine) palladium(0); diisopropylamine In benzene at 80℃;	97%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine at 95℃; for 7h; Inert atmosphere;
Sonogashira Cross-Coupling;
With tetrakis(triphenylphosphine) palladium(0); diisopropylamine In benzine at 80℃;

2,5-dimethyl-4-trimethylsilyl-1-phenylboronic acid (1059575-28-8) + 4-bromo-2,2'-bipyridyl (14162-95-9) → C21H24N2Si

Conditions	Yield
Stage #1: 2,5-dimethyl-4-trimethylsilyl-1-phenylboronic acid; 4-bromo-2,2'-bipyridyl With sodium carbonate In tetrahydrofuran; water for 0.25h; Inert atmosphere; Stage #2: With tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran; water at 85℃; for 21h; Inert atmosphere;	96%

([2,2':5',2''-terthiophen]-3'-ylethynyl)trimethylsilane + 4-bromo-2,2'-bipyridyl (14162-95-9) → 4-([2,2':5',2''-terthiophen]-3'-ylethynyl)-2,2'-bipyridine

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; 1,8-diazabicyclo[5.4.0]undec-7-ene; triethylamine In water; benzene for 18h; Inert atmosphere; Sealed tube;	95%

potassium hexafluorophosphate (17084-13-8) + [Rh2(4-(2-pyridyl)benzaldehyde(-1H))4Cl2] + 4-bromo-2,2'-bipyridyl (14162-95-9) → C34H23BrN4O2Rh(1+)*F6P(1-)

Conditions	Yield
Stage #1: [Rh2(4-(2-pyridyl)benzaldehyde(-1H))4Cl2]; 4-bromo-2,2'-bipyridyl In methanol; dichloromethane for 1.5h; Reflux; Stage #2: potassium hexafluorophosphate In water; acetonitrile	94%

10H-phenothiazine (92-84-2) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 10-(2,2'-bipyridin-4-yl)-10H-phenothiazine

Conditions	Yield
With chloro(2-dicyclohexylphosphino-2’,6’-diisopropoxy-1,1’-biphenyl)[2-(2’-amino-1,1‘-biphenyl)]palladium(II) 2nd generation; potassium tert-butylate In 1,4-dioxane at 110℃; for 18h; Inert atmosphere; Sealed tube;	93%

4-bromo-2,2'-bipyridyl (14162-95-9) → <2,2';4',4";2",2'">-quaterpyridine (133930-39-9)

Conditions	Yield
With bis(triphenylphosphine)nickel(II) chloride; zinc In N,N-dimethyl-formamide at 20℃; for 10h;	92%
With bis(triphenylphosphine)nickel(II) chloride; zinc In N,N-dimethyl-formamide at 20℃; for 12h; Inert atmosphere;	92%
With nickel(II) chloride hexahydrate; triphenylphosphine; zinc In N,N-dimethyl-formamide at 50℃; for 12h; Inert atmosphere;	19%

Thien-3-ylboronic acid (6165-69-1) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 4-(thiophen-3-yl)-2,2'-bipyridine

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); cetyltrimethylammonim bromide; potassium carbonate In water at 150℃; for 2h; Temperature; Suzuki-Miyaura Coupling; Inert atmosphere; Micellar solution; Microwave irradiation; Green chemistry;	92%
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In 1,2-dimethoxyethane at 80℃; for 0.5h; Inert atmosphere; Microwave irradiation;	80%

1,4-diethinyl-2,5-di(octadecyloxy)benzene (128424-46-4) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 1,4-bis(2',2"-bipyridine-4"-ylethinyl)-2,5-di(octadecyloxy)benzene

Conditions	Yield
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine In tetrahydrofuran for 24h; Condensation; Heating;	90%

4-bromo-2,2'-bipyridyl (14162-95-9) + lithium phenylacetylide (4440-01-1) → 4-(phenylethynyl)-2,2’-bipyridine (444085-26-1)

Conditions	Yield
Stage #1: lithium phenylacetylide With 9-methoxy-9-borabicyclo[3.3.1]nonane In tetrahydrofuran; hexane at -78℃; for 2h; Stage #2: 4-bromo-2,2'-bipyridyl; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran for 18h; Suzuki-type coupling; Heating; Further stages.;	90%

C28H34BNO4 + 4-bromo-2,2'-bipyridyl (14162-95-9) → C32H29N3O2

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In tetrahydrofuran; water at 85℃; for 23h; Inert atmosphere;	90%

4-bromo-2,2'-bipyridyl (14162-95-9) + potassium vinyltrifluoroborate → 4-ethynyl-2,2'-bipyridine (82761-36-2)

Conditions	Yield
With palladium diacetate; caesium carbonate; triphenylphosphine In tetrahydrofuran; water at 85℃; for 48h; Suzuki-Miyayra cross-coupling; Inert atmosphere; Sealed tube;	89%

4′-(4-boronatophenyl)-2,2′:6′,2′′-terpyridine (381218-96-8) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 4′-(2,2′-bipyridin-4-yl)-2,2′:6′-2′′-terpyridine

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In ethanol; water; toluene at 20℃; Suzuki Coupling; Inert atmosphere; Reflux; Schlenk technique;	89%

rhenium(I) pentacarbonyl bromide (14220-21-4) + 4-bromo-2,2'-bipyridyl (14162-95-9) → facial-bromotricarbonyl(4-bromo-2,2'-bipyridine)rhenium(I)

Conditions	Yield
In toluene for 2h; Reflux; Inert atmosphere;	86%

4,4,5,5-tetramethyl-2-(perylene-3-yl)-1,3,2-dioxaborolane (950761-81-6) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 3-(2,2’-bipyridine-4-yl)perylene (1456736-21-2)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); potassium carbonate In ethanol; toluene at 85 - 100℃; for 22.33h; Suzuki-Miyaura Coupling; Inert atmosphere;	85.9%

ethyl 3,5-diethynylbenzoate (437707-60-3) + 4-bromo-2,2'-bipyridyl (14162-95-9) → ethyl 3,5-bis(2,2’-bipyridin-4-ylethynyl)benzoate (1392217-94-5)

Conditions	Yield
With tris-(dibenzylideneacetone)dipalladium(0); copper(l) iodide; triethylamine; triphenylphosphine at 70℃; for 48h; Inert atmosphere;	85%

4-formylphenylboronic acid, (87199-17-5) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 4-(2,2'-bipyridyl-4-yl)benzaldehyde

Conditions	Yield
With 1,1'-bis(diphenylphosphino)ferrocene-palladium(II)dichloride dichloromethane complex; potassium carbonate In 1,4-dioxane; water for 6h; Suzuki-Miyaura Coupling; Reflux;	85%

ruthenium trichloride hydrate + 4-bromo-2,2'-bipyridyl (14162-95-9) → [RuCl2(4-bromo-2,2'-bipyridine)2] (1228182-23-7)

Conditions	Yield
With glucose; L-ascorbic acid In ethane-1,2-diol; H2O Ar; Ru compd. (7.3 mmol) heated at 80°C for 15 min in EG/H2O mixt. (3/1 v/v), ligand (14.4 mmol) added, heated at 100°C, glucose (1.1 mmol) added, stirred for 10 min, L-ascorbic acid (2.8 mmol) added, stirred for 30 min; cooled to 0°C, ppt. filtered off, washed (ether/acetone=4/1, ether);	84%

4-pyridylboronic acid (1692-15-5) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 2,2':6,2''-terpyridine (1148-79-4)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); potassium carbonate In 1,2-dimethoxyethane for 96h; Suzuki Coupling; Inert atmosphere; Schlenk technique; Reflux;	82.9%

4-bromo-2,2'-bipyridyl (14162-95-9) + (Sa)-2-(2,2'-bis(methoxymethoxy)-3'-(4,4,5-trimethyl-1,3,2-dioxaborolan-2-yl)-1,1'-binaphthyl-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane → (S)-3,3'-bis(2,2'-bipyridin-4-yl)-2,2'-bis(methoxymethoxy)-1,1'-binaphthyl

Conditions	Yield
Stage #1: 4-bromo-2,2'-bipyridyl With tetrakis(triphenylphosphine) palladium(0) In toluene at 20℃; for 0.166667h; Inert atmosphere; Stage #2: (Sa)-2-(2,2'-bis(methoxymethoxy)-3'-(4,4,5-trimethyl-1,3,2-dioxaborolan-2-yl)-1,1'-binaphthyl-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane With sodium carbonate In toluene for 72h; Inert atmosphere; Reflux;	82%

4′-ethynyl-2,2′-bipyridine (146548-24-5) + 4-bromo-2,2'-bipyridyl (14162-95-9) → bis(2,2'-bipyridin-4-yl)ethyne (146548-30-3)

Conditions	Yield
tetrakis(triphenylphosphine) palladium(0) In benzene at 80℃;	80%
With tetrakis(triphenylphosphine) palladium(0); diisopropylamine In benzene at 80℃;	80%

bis(4-methoxyphenyl)amine (101-70-2) + 4-bromo-2,2'-bipyridyl (14162-95-9) → C24H21N3O2

Conditions	Yield
With 1,1'-bis-(diphenylphosphino)ferrocene; tris-(dibenzylideneacetone)dipalladium(0); sodium t-butanolate In toluene at 140℃; for 48h; Inert atmosphere;	80%

cis-dichlorobis(2,2′-bipyridine)ruthenium(II) (345911-20-8, 19542-80-4, 158060-65-2, 34795-02-3, 15746-57-3) + ammonium hexafluorophosphate + 4-bromo-2,2'-bipyridyl (14162-95-9) → rac-[Ru(4-Br-2,2’-bipyridine)(2,2’-bipyridine)2](PF6)2

Conditions	Yield
Stage #1: cis-dichlorobis(2,2′-bipyridine)ruthenium(II); 4-bromo-2,2'-bipyridyl In ethanol; water for 4h; Reflux; Stage #2: ammonium hexafluorophosphate In water at 0℃; for 1h; Saturated solution;	80%

N,N-dimethyl-formamide (68-12-2, 33513-42-7) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 2,2'-bipyridine-4-carboxaldehyde (146581-82-0)

Conditions	Yield
Stage #1: 4-bromo-2,2'-bipyridyl With n-butyllithium In diethyl ether; hexane; toluene at -78℃; for 1.5h; Inert atmosphere; Stage #2: N,N-dimethyl-formamide In diethyl ether; hexane; toluene at -78℃; for 1.5h; Inert atmosphere;	80%

(rac)-3,3'-bis(pinacolboryl)-2,2'-bis(methoxymethoxy)-1,1'-binaphhyl (955405-38-6, 260441-99-4, 260442-17-9) + 4-bromo-2,2'-bipyridyl (14162-95-9) → ((C10H5)(OCH2OCH3)(C5H3N)(C5H4N))2 (1269460-56-1, 1246528-38-0, 1257519-10-0)

Conditions	Yield
Stage #1: 4-bromo-2,2'-bipyridyl With tetrakis(triphenylphosphine) palladium(0) In toluene at 20℃; for 0.166667h; Inert atmosphere; Stage #2: (rac)-3,3'-bis(pinacolboryl)-2,2'-bis(methoxymethoxy)-1,1'-binaphhyl With sodium carbonate In toluene for 72h; Suzuki coupling; Inert atmosphere; Reflux;	79%

ammonium hexafluorophosphate + mer-Re(CO)3(PEt3)2Br (178212-01-6) + 4-bromo-2,2'-bipyridyl (14162-95-9) → [Re(4-bromo-2,2'-bipyridine)(CO)2(PEt3)2](PF6)

Conditions	Yield
Stage #1: mer-Re(CO)3(PEt3)2Br With silver trifluoromethanesulfonate In tetrahydrofuran for 3h; Reflux; Inert atmosphere; Stage #2: 4-bromo-2,2'-bipyridyl In toluene at 90℃; for 36h; Heating; Inert atmosphere; Stage #3: ammonium hexafluorophosphate In methanol	77%

4'-ethynyl-2,2':6',6-terpyridine (149817-60-7) + 4-bromo-2,2'-bipyridyl (14162-95-9) → 4'-(2,2'-bipyridin-4-ylethynyl)-2,2':6',2''-terpyridine (146548-34-7)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); diisopropylamine In benzene at 80℃; for 22h;	75%

Upstream product

• 30091-53-3 3-(pyridin-2-yl)-1,2,4-triazine 
• 994-89-8 tributylethynyltin 
• 14163-00-9 4-nitro-2,2'-bipyridine N-oxide 
• 14163-01-0 4-nitro-2,2′-bipyridine N-oxide 
• 7275-43-6 [2,2']bipyridinyl 1,1'-dioxide 
• 33421-43-1 2,2'-bipyridyl N-oxide 
• 366-18-7 [2,2]bipyridinyl 
• 249644-59-5 4-bromo-2,2′-bipyridine-1,1′-dioxide 
• 14163-03-2 4-bromo-2,2’-bipyridine N-oxide 

Downstream Products

• 1242658-09-8 4-(4-formyl-2,6-dimethylphenyl)-2,2'-bipyridine 
• 1242658-07-6 4-(4-formyl-2-methylphenyl)-2,2'-bipyridine 
• 374561-03-2 4-(4-aminophenyl)-2,2'-bipyridine 
• 1148-79-4 2,2':6,2''-terpyridine 

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In this work, two ligands: 4-(trans-2-Methyl-2-butenoic acid)-2,2'-bipyridine) (L1) and 5-(trans-2-methyl-2-butenoic acid)-1,10-phenanthroline (L2), with the corresponding mixed-ligand heteroleptic Ru(II) complex were synthesized and characterized by FT-IR, 1H-, 13C-NMR spectroscopy and elemental analysis. The influence of the mixed functionalized polypyridyl ruthenium(II) complex on the photophysical and electrochemical properties were investigated and compared to individual single-ligand homoleptic complexes. Interestingly, the mixed-ligand complex formulated as [RuL1L2(NCS)2] exhibits broad and intense metal-to-ligand charge transfer (MLCT) absorption with a high molar extinction coefficient (λmax = 514 nm, ε = 69,700 M -1 cm-1), better than those of individual single-ligand complexes, [Ru(L1)2(NCS)2] and [Ru(L2) 2(NCS)2], and a strong photoluminescence intensity ratio in the red region at λem = 686 nm. The electrochemical properties of the complex indicated that the redox processes are ligand-based.

2-Nitroimidazole-ruthenium polypyridyl complex as a new conjugate for cancer treatment and visualization

A novel long-lifetime highly luminescent ruthenium polypyridyl complex containing 2-nitroimidazole moiety [Ru(dip)2(bpy-2-nitroIm)]Cl 2 (dip = 4,7-diphenyl-1,10-phenanthroline, bpy-2-nitroIm = 4-[3-(2-nitro-1H-imidazol-1-yl)propyl]-2,2′-bipyridine) has been designed cancer treatment and imaging. The luminescence properties of the synthesized compound strongly depend on the oxygen concentration. Under oxygen-free conditions quantum yield of luminescence and the average lifetime of emission were found to be 0.034 and 1.9 μs, respectively, which is ca. three times higher in comparison to values obtained in air-equilibrated solution. The binding properties of the investigated ruthenium complex to human serum albumin have been studied and the apparent binding constant for the formation of the protein-ruthenium adduct was determined to be 1.1 × 105 M - 1. The quantum yield and the average lifetime of emission are greatly enhanced upon binding of ruthenium compound to the protein. The DNA binding studies revealed two distinguished binding modes which lead to a decrease in luminescence intensity of ruthenium complex up to 60% for [DNA]/[Ru] 80. Preliminary biological studies confirmed fast and efficient accumulation of the ruthenium complex inside cells. Furthermore, the ruthenium complex was found to be relatively cytotoxic with LD50 of 12 and 13 μM for A549 and CT26 cell lines, respectively, under normoxic conditions. The retention and cellular uptake of ruthenium complex is enhanced under hypoxic conditions and its LD 50 decreases to 8 μM for A549 cell line.