14432-16-7

Basic information

• Product Name: 2-Chloro-4-nitropyridine 1-oxide
• Synonyms: OTAVA-BB BB7017520053;AURORA 23245;(2-CHLOROPYRIDIN-4-YL)(HYDROXY)OXOAMMONIUM;2-CHLORO-4-NITROPYRIDINE 1-OXIDE;2-CHLORO-4-NITROPYRIDINE-N-OXIDE;AKOS BBS-00001358;2-Chloro-4-nitro-1-oxidopyridin-1-ium;2-Chloro-4-nitropyridine-N-oxide ,97%
• CAS NO: 14432-16-7
• Molecular Formula: C₅H₃ClN₂O₃
• Molecular Weight: 174.54
• EINECS: 238-404-6
• Product Categories: Pyridine;Pyridines;C5Heterocyclic Building Blocks;Halogenated Heterocycles;Heterocyclic Building Blocks
• Mol File: 14432-16-7.mol
• Article Data: 17

Chemical Properties

• Melting Point: 52-56 °C(lit.)
• Boiling Point: 405.9 °C at 760 mmHg
• Flash Point: 223 °F
• Appearance: light yellow solid
• Density: 1.62 g/cm³
• PKA: -2.53±0.10(Predicted)
• BRN: 145697
• CAS DataBase Reference: 2-Chloro-4-nitropyridine 1-oxide(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Chloro-4-nitropyridine 1-oxide(14432-16-7)
• EPA Substance Registry System: 2-Chloro-4-nitropyridine 1-oxide(14432-16-7)

Safety Data

• Hazard Codes: T
• Statements: 23/24/25-36/37/38
• Safety Statements: 26-36-45-36/37/39-28
• RIDADR: UN 2811 6.1/PG 3
• WGK Germany: 3
• HazardClass: 6.1
• PackingGroup: III
• Hazardous Substances Data: 14432-16-7(Hazardous Substances Data)

Usage

Chemical Properties

light yellow solid

InChI:InChI=1/C5H4ClN2O3/c6-5-3-4(8(10)11)1-2-7(5)9/h1-3,5H/q+1

Synthetic route

2-chloropyridine-N-oxide (2402-95-1) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
nitration;	93%
With sulfuric acid; nitric acid at 90℃; for 4h;	78%
With sulfuric acid; nitric acid for 2h; Nitration;	72%

2-chloro-4-nitropyridine (23056-36-2) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
Stage #1: 2-chloro-4-nitropyridine With urea hydrogen peroxide adduct; trifluoroacetic acid In dichloromethane at 0 - 20℃; for 72h; Stage #2: With sodium dithionite In dichloromethane; water for 0.25h; Stage #3: With hydrogenchloride In dichloromethane; water	90%
With urea hydrogen peroxide adduct; trifluoroacetic anhydride In dichloromethane at 0 - 20℃; for 4.5h;	84%

2-chloropyridine N-oxide hydrochloride (20295-64-1) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
With sulfuric acid; nitric acid at 90 - 100℃; for 2.5h;	82.5%
With sodium hydroxide; nitric acid In sulfuric acid	37%
With sulfuric acid; nitric acid In (2S)-N-methyl-1-phenylpropan-2-amine hydrate
With sulfuric acid; nitric acid In (2S)-N-methyl-1-phenylpropan-2-amine hydrate

2-chloropyridine (109-09-1) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: 91 percent / aq. H2O2 / trifluoroacetic acid / 4 h 2: 72 percent / aq. HNO3, H2SO4 / 2 h View Scheme
Multi-step reaction with 2 steps 1: 30percent aq. H2O2, AcOH / 48 h / 60 °C 2: HNO3, conc. H2SO4 / 2.5 h / 90 °C View Scheme
Multi-step reaction with 2 steps 1: H2O2 / acetic anhydride 2: HNO3, H2SO4 View Scheme

2-aminopyridine N-oxide (14150-95-9) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
Multi-step reaction with 3 steps 1: concentrated sulfuric acid; peroxomonosulfuric acid 3: concentrated sulfuric acid; nitric acid View Scheme

4-carboxy-2-nitropyridine N-oxide (2403-02-3) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7)

Conditions	Yield
Multi-step reaction with 2 steps 2: concentrated sulfuric acid; nitric acid View Scheme

2-chloropyridine-N-oxide (2402-95-1) → 2-chloro-4-nitropyridine-N-oxide (14432-16-7) + 2-Chloro-4-nitropyidine-N oxide

Conditions	Yield
With sulfuric acid; nitric acid

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + 1-amino-propan-2-ol → 1-(4-nitro-1-oxy-pyridin-2-ylamino)-propan-2-ol

Conditions	Yield
In ethanol at 80℃; for 13h;	99%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 4-Amino-2-chloropyridine (14432-12-3)

Conditions	Yield
With hydrogenchloride; iron In ethanol for 3h; Reduction; Heating;	95%
With hydrogen; Ra-Ni In methanol	90%
With hydrogenchloride; iron In ethanol; water Reflux;	85%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2,4-dichloropyridine 1-oxide (13602-59-0)

Conditions	Yield
With acetyl chloride at 70 - 75℃; for 0.416667h;	94%
With acetyl chloride for 0.666667h;	80%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + sodium methylate (124-41-4) → 2-chloro-4-methoxypyridine N-oxide (38608-87-6)

Conditions	Yield
With sulfuric acid; nitric acid In methanol at 20℃; for 48h;	94%
In methanol

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + dimethyl amine (124-40-3) → 2-(dimethylamino)-4-nitropyridine 1-oxide (36100-42-2)

Conditions	Yield
In tetrahydrofuran; ethanol at 90℃; for 5h;	91%
In water at 100℃; Inert atmosphere; Sealed tube;

(S)-N-(2,6-diisopropyl-phenyl)pyrrolidine-2-carboxamide (943784-90-5) + 2-chloro-4-nitropyridine-N-oxide (14432-16-7) → (S)-2-(2-((2,6-diisopropylphenyl)carbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	90%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2-chloro-4-nitropyridine (23056-36-2)

Conditions	Yield
With phosphorus trichloride In dichloromethaneu for 4h; Reflux;	88%
With phosphorus trichloride In chloroform at 20℃; Heating / reflux;	78%
With ethyl acetate; phosphorus trichloride

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + (2S)-N-benzhydrylpyrrolidine-2-carboxamide (748149-61-3) → (S)-2-(2-(benzhydrylcarbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	88%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + histamine (51-45-6) → 4-{[2-(1H-Imidazol-4-yl)ethyl]amino}-2-chloropyridine + [2-(1H-Imidazol-4-yl)-ethyl]-(5-nitro-1-oxy-pyridin-2-yl)-amine

Conditions	Yield
With potassium hydrogencarbonate In isopropyl alcohol at 21℃; for 72h;	A 87% B n/a
With potassium hydrogencarbonate In isopropyl alcohol at 21℃; for 72h;

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + ethyl spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-13-5) → ethyl 1'-(4-nitro-1-oxidopyridin-2-yl)spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-16-8)

Conditions	Yield
With triethylamine In tert-Amyl alcohol at 50℃;	87%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + 1-thiopropane (107-03-9) → 2-chloro-4-(propylsulfanyl)pyridine-N-oxide (1186127-82-1) + 4-nitro-2-(propylsulfanyl)pyridine-N-oxide (1186127-84-3)

Conditions	Yield
With sodium acetate In ethanol at 50℃;	A 86% B 10%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + (2S)-N-phenylpyrrolidine-2-carboxamide (25746-83-2, 64030-43-9, 104261-87-2) → (S)-4-nitro-2-(2-(phenylcarbamoyl)pyrrolidin-1-yl)pyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	86%

(S)-N-(2,6-diethylphenyl)pyrrolidine-2-carboxamide + 2-chloro-4-nitropyridine-N-oxide (14432-16-7) → (S)-2-(2-((2,6-diethylphenyl)carbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	85%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + L-proline tert-butylamide (128018-18-8) → (S)-2-(2-(tert-butylcarbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	82%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + methyl spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-12-4) → methyl 1'-(4-nitro-1-oxidopyridin-2-yl)spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-15-7)

Conditions	Yield
With triethylamine In tert-Amyl alcohol at 50℃;	79%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + (S)-N-(3,5-bis(trifluoromethyl)phenyl)pyrrolidine-2-carboxamide (875542-94-2) → (S)-2-(2-((3,5-bis(trifluoromethyl)phenyl)carbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	78%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + cyclohexylamine (108-91-8) → cyclohexyl-(4-nitro-1-oxy-pyridin-2-yl)-amine (75291-50-8)

Conditions	Yield
In ethanol at 80℃; for 13h;	76%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + isopropyl spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-14-6) → isopropyl 1'-(4-nitro-1-oxidopyridin-2-yl)spiro[indole-3,4'-piperidine]-1(2H)-dicarboxylate (937255-17-9)

Conditions	Yield
With triethylamine In tert-Amyl alcohol at 50℃;	75%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + 7-methoxy-3-piperidin-4-yl-1,3,4,5-tetrahydro-benzo[d][1,3]diazepin-2-one (291509-79-0) → 7-methoxy-3-(4'-nitro-1'-oxy-3,4,5,6-tetrahydro-2H-[1,2']bipyridinyl-4-yl)-1.3.4,5-tetrahydro-benzo[d][1,3]diazepin-2-one (1231750-46-1)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 60℃; for 2h;	75%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + methylamine (74-89-5) → 2-methylamino-4-nitropyridine N-oxide (75291-48-4)

Conditions	Yield
	74%

methanol (67-56-1) + 2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2-chloro-4-methoxypyridine N-oxide (38608-87-6)

Conditions	Yield
With sodium hydride at 0℃; for 0.5h;	70%

methanol (67-56-1) + 2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2,4-dimethoxypyridine N-oxide (6890-63-7)

Conditions	Yield
With sodium for 1h; Heating;	70%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2,6-dichloro-4-nitro-pyridine (25194-01-8)

Conditions	Yield
With trichlorophosphate at 110℃; for 2.5h;	70%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + 2,3-dihydrospiro[indene-1,4-piperidine]-3-amine (937254-70-1) → 1'-(4-nitro-1-oxidopyridin-2-yl)-2,3-dihydrospiro[indene-1,4'-piperidin]-3-amine (937254-71-2)

Conditions	Yield
Stage #1: 2,3-dihydrospiro[indene-1,4-piperidine]-3-amine With sodium carbonate In 4-methyl-2-pentanone at 110℃; for 3h; Stage #2: 2-chloro-4-nitropyridine-N-oxide In 4-methyl-2-pentanone at 80℃;	70%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + (S)-N-methyl-N-phenyl-pyrrolidine-2-carboxamide (1173169-85-1) → (S)-2-(2-(methyl(phenyl)carbamoyl)pyrrolidin-1-yl)-4-nitropyridine 1-oxide

Conditions	Yield
With triethylamine In tetrahydrofuran at 70℃; for 10h;	70%

2-chloro-4-nitropyridine-N-oxide (14432-16-7) + tert-butyl 3-aminopiperidine-1-carboxylate → 3-(4-nitro-1-oxy-pyridin-2-ylamino)-piperidine-1-carboxylic acid tert-butyl ester

Conditions	Yield
In ethanol at 80℃; for 13h;	67%

morpholine (110-91-8) + 2-chloro-4-nitropyridine-N-oxide (14432-16-7) → 2-(N-morpholinyl)-4-nitropyridine N-oxide (35981-62-5)

Conditions	Yield
In ethanol at 20℃; for 3h;	63%
In ethanol

Upstream product

• 23056-36-2 2-chloro-4-nitropyridine 
• 2402-95-1 2-chloropyridine-N-oxide 
• 20295-64-1 2-chloropyridine N-oxide hydrochloride 
• 2403-02-3 4-carboxy-2-nitropyridine N-oxide 
• 14150-95-9 2-aminopyridine N-oxide 
• 109-09-1 2-chloropyridine 

Downstream Products

• 129836-41-5 2-allyloxy-4-nitropyridine N-oxide 
• 129836-50-6 2-benzyloxy-4-nitropyridine N-oxide 
• 13602-59-0 2,4-dichloropyridine-N-oxide 
• 1029803-69-7 4-(2-benzyloxyethoxy)-2-chloropyridine 
• 881844-11-7 4-chloro-1-(p-methoxybenzyl)-1H-imidazo[4,5-c]pyridine 
• 6811-77-4 3-deazaadenine 
• 39217-08-8 2-chloropyridine-3,4-diamine 

Relevant articles and documents

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A 2 - chloro -4 - aminopyridine preparation method

The invention belongs to the field of organic synthesis, in particular relates to a 2 - chloro - 4 - aminopyridine preparation method, comprises the following steps: (1) to 2 - chloro pyridine as raw materials, chloroform as solvent, under the action of the meta-chloroperoxybenzoic acid to produce 2 - chloro pyridine oxide; (2) 2 - chloro pyridine oxide by the concentrated nitric acid in concentrated sulfuric acid the acid produced by the reaction of a 2 - chloro - 4 - nitro pyridine nitrogen oxides; (3) 2 - chloro - 4 - nitro pyridine nitrogen oxide reduction is 2 - chloro - 4 - aminopyridine. The beneficial effect of the invention is: mild reaction conditions, is easy to operate, after treatment is simple, and easy to enlarge production, is extremely suitable for industrial production; good catalytic effect, high yield; low prices of raw materials, the production cost is low.

9H-PYRROLO-DIPYRIDINE DERIVATIVES

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