24485-01-6

Basic information

• Product Name: 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro-
• Synonyms: 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro-;5,7-dichloro-1H-imidazo[4,5-b]pyridine;Nsc264046;5,7-Dichloroimidazo[4,5-b]pyridine;7-dichloro-1H-iMidazo[4;1H-IMidazo[4,5-b]pyridine, 5,7-dichloro-
• CAS NO: 24485-01-6
• Molecular Formula: C₆H₃Cl₂N₃
• Molecular Weight: 188.01
• Product Categories: CHIRAL CHEMICALS;Heterocycle-Pyridine series
• Mol File: 24485-01-6.mol
• Article Data: 8

Chemical Properties

• Melting Point: 273-274 °C
• Boiling Point: 416.867 °C at 760 mmHg
• Flash Point: 238.425 °C
• Appearance: /
• Density: 1.675 g/cm³
• Vapor Pressure: 0.00936mmHg at 25°C
• Refractive Index: 1.768
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• PKA: 5.37±0.40(Predicted)
• CAS DataBase Reference: 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro-(CAS DataBase Reference)
• NIST Chemistry Reference: 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro-(24485-01-6)
• EPA Substance Registry System: 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro-(24485-01-6)

Safety Data

• Hazardous Substances Data: 24485-01-6(Hazardous Substances Data)

Usage

General Description

5,7-dichloro-3H-Imidazo[4,5-b]pyridine is a chemical compound with a molecular formula C7H3Cl2N3. It belongs to the class of imidazopyridine compounds and is characterized by the presence of two chlorine atoms at the 5th and 7th positions. 3H-Imidazo[4,5-b]pyridine, 5,7-dichloro- is a heterocyclic organic molecule that is used in various fields including pharmaceuticals, agrochemicals, and material science. It has been studied for its potential biological activities and pharmacological properties, making it an important molecule for drug discovery and development. The presence of chlorine atoms in its structure can influence its reactivity and biological interactions, making it a valuable compound for further research and applications.

InChI:InChI=1/C6H3Cl2N3/c7-3-1-4(8)11-6-5(3)9-2-10-6/h1-2,5H

Synthetic route

7-nitro-1H-imidazo[4,5-b]pyridine 4-oxide (14432-11-2) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
With trichlorophosphate In N,N-dimethyl-formamide at 0 - 120℃; for 3h;	90%
With trichlorophosphate at 100℃; for 2.5h;	86%
Multi-step reaction with 2 steps 1: 51 percent / H2 / 5percent Pd on charcoal / ethanol / 5 h / 2280 Torr / Ambient temperature 2: phosphoryl chloride View Scheme

7-nitroimidazo<4,5-b>pyridine 4-oxide (14432-11-2) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
With trichlorophosphate In N,N-dimethyl-formamide for 2h; Heating;	80%
With trichlorophosphate In N,N-dimethyl-formamide at 115℃; for 0.166667h;	50%
With trichlorophosphate In N,N-dimethyl-formamide
With trichlorophosphate In N,N-dimethyl-formamide

7-Amino-3H-imidazo<4,5-b>pyridine 4-N-Oxide (77712-93-7) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
With trichlorophosphate

3H-Imidazo<4,5-b>pyridine 4-N-oxide (6863-46-3) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 67 percent / trifluoroacetic acid; HNO3 / 3 h / 90 °C 2: 80 percent / POCl3 / dimethylformamide / 2 h / Heating View Scheme
Multi-step reaction with 2 steps 1: trifluoroacetic acid; nitric acid / 4 h / 90 °C 2: trichlorophosphate / N,N-dimethyl-formamide / 0.17 h / 115 °C View Scheme

3H-imidazo[4,5-b]pyridine (273-21-2) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: 96 percent / aq. H2O2; acetic acid / 19 h / 60 - 70 °C 2: 67 percent / trifluoroacetic acid; HNO3 / 3 h / 90 °C 3: 80 percent / POCl3 / dimethylformamide / 2 h / Heating View Scheme
Multi-step reaction with 3 steps 1: 3-chloro-benzenecarboperoxoic acid / 72 h / 20 °C 2: trifluoroacetic acid; nitric acid / 4 h / 90 °C 3: trichlorophosphate / N,N-dimethyl-formamide / 0.17 h / 115 °C View Scheme

7-chloro-3H-imidazo[4,5-b]pyridine-4-oxide → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
With trichlorophosphate In water

1H-Imidazo[4,5-b]pyridine (273-21-2) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: dihydrogen peroxide / acetic acid / 50 - 70 °C 2: nitric acid / trifluoroacetic acid / 3.5 h / 0 - 90 °C 3: trichlorophosphate / N,N-dimethyl-formamide / 3 h / 0 - 120 °C View Scheme

Imidazo<4,5-b>pyridine 4-Oxide (6863-46-3) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: nitric acid / trifluoroacetic acid / 3.5 h / 0 - 90 °C 2: trichlorophosphate / N,N-dimethyl-formamide / 3 h / 0 - 120 °C View Scheme

2,3-Diaminopyridine (452-58-4) → 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: orthoformic acid triethyl ester / 3 h / 145 °C 1.2: 2 h / 110 °C 1.3: activated charcoal / 20 °C 2.1: 3-chloro-benzenecarboperoxoic acid / 72 h / 20 °C 3.1: trifluoroacetic acid; nitric acid / 4 h / 90 °C 4.1: trichlorophosphate / N,N-dimethyl-formamide / 0.17 h / 115 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + 1,2,3,5-tetraacetylribose (13035-61-5) → 1-(5,7-dichloro-imidazo[4,5-b]pyridin-3-yl)-O2,O3-isopropylidene-β-D-1-deoxy-ribofuranose (57521-46-7)

Conditions	Yield
With tin(IV) chloride In acetonitrile at 20℃;	82%
With tin(IV) chloride
Stage #1: 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine With N,O-bis-(trimethylsilyl)-acetamide In acetonitrile at 85℃; for 1h; Stage #2: 1,2,3,5-tetraacetylribose With trimethylsilyl trifluoromethanesulfonate In acetonitrile at 85℃; for 4h;

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + (2S,3R,5S)-5-((benzoyloxy)methyl)tetrahydrofuran-2,3-diyl diacetate (90580-88-4) → 3-(2-O-acetyl-5-O-benzoyl-3-deoxy-D-ribofuranosyl)-5,7-dichloro-3H-imidazo[4,5-b]pyridine

Conditions	Yield
With toluene-4-sulfonic acid at 160℃;	81%

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + (2S,3R,5S)-5-((benzoyloxy)methyl)tetrahydrofuran-2,3-diyl diacetate (90580-88-4) → 3-(2-O-acetyl-5-O-benzoyl-3-deoxy-β-D-ribofuranosyl)-5,7-dichloro-3H-imidazo[4,5-b]pyridine (232277-31-5)

Conditions	Yield
With tin(IV) chloride In acetonitrile Substitution;	69%
With tin(IV) chloride In acetonitrile	69%

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + (2S,3R,5S)-5-((benzoyloxy)methyl)tetrahydrofuran-2,3-diyl diacetate (90580-88-4) → 5,7-dichloro-3-deoxy-3-deoxy-β-D-ribofuranosyl-3H-imidazo[4,5-b]pyridine (232277-32-6) + 5,7-dichloro-3-(3-deoxy-α-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridine (232277-35-9)

Conditions	Yield
Stage #1: 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine; (2S,3R,5S)-5-((benzoyloxy)methyl)tetrahydrofuran-2,3-diyl diacetate With toluene-4-sulfonic acid Stage #2: With ammonia In methanol	A 56% B 29%

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + (2S,3R,5S)-5-((benzoyloxy)methyl)tetrahydrofuran-2,3-diyl diacetate (90580-88-4) → 3-(2-O-acetyl-5-O-benzoyl-3-deoxy-β-D-ribofuranosyl)-5,7-dichloro-3H-imidazo[4,5-b]pyridine (232277-31-5) + 3-(2-O-acetyl-5-O-benzoyl-3-deoxy-α-D-ribofuranosyl)-5,7-dichloro-3H-imidazo[4,5-b]pyridine

Conditions	Yield
toluene-4-sulfonic acid at 160℃; for 0.166667h; Glycosylation;	A 52% B 29%
With toluene-4-sulfonic acid at 160℃; for 0.166667h; Substitution; Title compound not separated from byproducts;
With toluene-4-sulfonic acid Heating;

1-(bromomethyl)-2-methyl-3-(trifluoromethyl)benzene (261952-16-3) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-dichloro-3-(2-methyl-3-(trifluoromethyl)benzyl)-3H-imidazo[4,5-b]pyridine (1445877-12-2)

Conditions	Yield
Stage #1: 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine With potassium carbonate In N,N-dimethyl-formamide for 0.416667h; Stage #2: 1-(bromomethyl)-2-methyl-3-(trifluoromethyl)benzene In N,N-dimethyl-formamide at 20℃;	47.6%

benzyl chloride (100-44-7) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 2,6-dichloro-9-benzyl-1-deazapurine (500896-84-4)

Conditions	Yield
Stage #1: 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine With potassium carbonate In N,N-dimethyl-formamide for 0.5h; Stage #2: benzyl chloride In N,N-dimethyl-formamide at 20℃; for 16h;	42%

3,4-dihydro-2H-pyran (110-87-2) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5 ,7-dichloro-3-(tetrahydro-2H-pyran-2-yl)-3H-imidazo[4,5-b]pyridine

Conditions	Yield
With toluene-4-sulfonic acid In tetrahydrofuran at 70℃; for 16h;	35.53%

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) + 2-(bromomethyl)naphthalene (3163-27-7) → 5,7-dichloro-3-(1-naphthalenylmethyl)-3H-imidazo[4,5-b]pyridine (1445877-14-4)

Conditions	Yield
Stage #1: 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine With potassium carbonate In N,N-dimethyl-formamide for 25h; Stage #2: 2-(bromomethyl)naphthalene at 20℃;	26.2%

Hoffer's chlorosugar (3601-89-6, 4330-21-6, 52304-86-6, 3056-12-0, 141846-57-3) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-dichloro-1-(2-deoxy-β-D-erythro-pentofuranosyl)-1H-imidazo<4,5-b>pyridine + 5,7-dichloro-3-(2-deoxy-α-D-erythro-pentofuranosyl)-3H-imidazo<4,5-b>pyridine + 5,7-dichloro-3-(2-deoxy-β-D-erythro-pentofuranosyl)-3H-imidazo[4,5-b]pyridine (159944-82-8)

Conditions	Yield
With ammonia; sodium hydride 1.) CH3CN, 0 deg C, 3 h, 2.) MeOH, RT, 36 h; Yield given. Multistep reaction. Yields of byproduct given;

Hoffer's chlorosugar (3601-89-6, 4330-21-6, 52304-86-6, 3056-12-0, 141846-57-3) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-dichloro-3-(2-deoxy-3,5-di-O-p-toluoyl-β-D-erythro-pentofuranosyl)-3H-imidazo<4,5-b>pyridine + 5,7-dichloro-3-(2-deoxy-3,5-di-O-p-toluoyl-α-D-erythro-pentofuranosyl)-3H-imidazo<4,5-b>pyridine

Conditions	Yield
With sodium hydride at 0℃; for 3h;

2,3-dideoxy-5-O-<(1,1-dimethylethyl)dimethylsilyl>-α/β-D-glycero-pentofuranosyl chloride (131487-19-9) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 3-[(2R,5S)-5-(tert-Butyl-dimethyl-silanyloxymethyl)-tetrahydro-furan-2-yl]-5,7-dichloro-3H-imidazo[4,5-b]pyridine

Conditions	Yield
Yield given;

methyl 2,3-dideoxy-5-O-(4-methylbenzoyl)-D-glycero-pentofuranoside (133635-44-6) + 5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-dichloro-3-(2,3-dideoxy-5-O-p-toluoyl-α-D-glycero-pentofuranosyl)-3H-imidazo<4,5-b>pyridine + 5,7-dichloro-3-(2,3-dideoxy-5-O-p-toluoyl-β-D-glycero-pentofuranosyl)-3H-imidazo<4,5-b>pyridine (165126-97-6)

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-diphenyl-3H-imidazo[4,5-b]pyridine

Conditions	Yield
Multi-step reaction with 3 steps 1.1: K2CO3 / dimethylformamide / 0.5 h 1.2: 42 percent / dimethylformamide / 16 h / 20 °C 2.1: 91 percent / K2CO3 / Pd(PPh3)4 / toluene / 0.5 h / 150 °C / microwave irradiation 3.1: 41 percent / ammonium formate / Pd(OH)2/C / ethanol / 0.33 h / 140 - 150 °C / microwave irradiation View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 3-benzyl-5,7-diphenyl-3H-imidazo[4,5-b]pyridine (929533-19-7)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: K2CO3 / dimethylformamide / 0.5 h 1.2: 42 percent / dimethylformamide / 16 h / 20 °C 2.1: 91 percent / K2CO3 / Pd(PPh3)4 / toluene / 0.5 h / 150 °C / microwave irradiation View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → (3R,5S)-2-(5,7-Dichloro-imidazo[4,5-b]pyridin-3-yl)-5-hydroxymethyl-tetrahydro-furan-3-ol

Conditions	Yield
Multi-step reaction with 2 steps 1: 81 percent / TsOH / 160 °C 2: 85 percent / NH3 / methanol / 20 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5-chloro-7-benzylsulfanyl-3-β-D-ribofuranosyl-3H-imidazo[4,5-b]pyridine

Conditions	Yield
Multi-step reaction with 3 steps 1: SnCl4 2: 85 percent / triethylamine / dimethylformamide / 18 h / 20 °C 3: 65 percent / ammonia / methanol / 18 h / 0 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5-chloro-7-(4-nitrobenzylsulfanyl)-3-β-D-ribofuranosyl-3H-imidazo[4,5-b]pyridine

Conditions	Yield
Multi-step reaction with 3 steps 1: SnCl4 2: 75 percent / triethylamine / dimethylformamide / 18 h / 20 °C 3: 88 percent / ammonia / methanol / 18 h / 0 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5-chloro-7-(benzylsulfanyl)-3-(2',3',5'-tri-O-acetyl-β-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridine (566194-66-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: SnCl4 2: 85 percent / triethylamine / dimethylformamide / 18 h / 20 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5-chloro-7-(4-nitrobenzylsulfanyl)-3-(2',3',5'-tri-O-acetyl-β-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridine (566194-68-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: SnCl4 2: 75 percent / triethylamine / dimethylformamide / 18 h / 20 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 7-amino-3-(3-deoxy-β-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridine

Conditions	Yield
Multi-step reaction with 4 steps 1: 69 percent / SnCl4 / acetonitrile 2: NH3 / methanol 3: NH3 / 130 °C 4: H2 / Pd-C View Scheme
Multi-step reaction with 4 steps 1: TsOH / Heating 2: NH3 / methanol 3: NH3 / 130 °C 4: H2 / Pd-C View Scheme
Multi-step reaction with 3 steps 1.1: p-toluenesulfonic acid 1.2: 56 percent / NH3 / methanol 2.1: NH3 / 130 °C 3.1: H2 / Pd-C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 5,7-dichloro-3-deoxy-3-deoxy-β-D-ribofuranosyl-3H-imidazo[4,5-b]pyridine (232277-32-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 69 percent / SnCl4 / acetonitrile 2: NH3 / methanol View Scheme
Multi-step reaction with 2 steps 1: TsOH / Heating 2: NH3 / methanol View Scheme
Multi-step reaction with 2 steps 1: 69 percent / SnCl4 / acetonitrile 2: 85 percent / NH3 / methanol / 20 °C View Scheme
Multi-step reaction with 2 steps 1: p-TsOH / 0.17 h / 160 °C 2: 85 percent / NH3 / methanol / 20 °C View Scheme

5,7-dichloro-3H-imidazo<4,5-b>pyrimidine (24485-01-6) → 7-amino-5-chloro-3-(3-deoxy-β-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridine (232277-33-7)

Conditions	Yield
Multi-step reaction with 3 steps 1: 69 percent / SnCl4 / acetonitrile 2: NH3 / methanol 3: NH3 / 130 °C View Scheme
Multi-step reaction with 3 steps 1: TsOH / Heating 2: NH3 / methanol 3: NH3 / 130 °C View Scheme
Multi-step reaction with 2 steps 1.1: p-toluenesulfonic acid 1.2: 56 percent / NH3 / methanol 2.1: NH3 / 130 °C View Scheme

Upstream product

• 273-21-2 1H-Imidazo[4,5-b]pyridine 
• 6863-46-3 Imidazo<4,5-b>pyridine 4-Oxide 
• 27048-04-0 2-amino-6-chloro-3-nitropyridine 
• 40851-95-4 6-chloropyridine-2,3-diamine 
• 452-58-4 2,3-Diaminopyridine 
• 273-21-2 3H-imidazo[4,5-b]pyridine 
• 6863-46-3 3H-Imidazo<4,5-b>pyridine 4-N-oxide 
• 14432-11-2 7-nitroimidazo<4,5-b>pyridine-4-oxide 
• 14432-11-2 7-nitro-1H-imidazo[4,5-b]pyridine 4-oxide 
• 77712-93-7 7-Amino-3H-imidazo<4,5-b>pyridine 4-N-Oxide 

Downstream Products

• 165126-97-6 5,7-dichloro-3-(2,3-dideoxy-5-O-p-toluoyl-β-D-glycero-pentofuranosyl)-3H-imidazo<4,5-b>pyridine 
• 232277-31-5 3-(2-O-acetyl-5-O-benzoyl-3-deoxy-β-D-ribofuranosyl)-5,7-dichloro-3H-imidazo[4,5-b]pyridine 
• 500896-84-4 2,6-dichloro-9-benzyl-1-deazapurine 
• 929533-19-7 3-benzyl-5,7-diphenyl-3H-imidazo[4,5-b]pyridine 
• 1445877-12-2 5,7-dichloro-3-(2-methyl-3-(trifluoromethyl)benzyl)-3H-imidazo[4,5-b]pyridine 
• 1445877-04-2 3-(2-methyl-3-(trifluoromethyl)benzyl)-5-morpholino-3H-imidazo[4,5-b]pyridin-7-ol 

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