183438-97-3

Basic information

• Product Name: 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI)
• Synonyms: 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI);2-Pyridinecarboxaldehyde,6-ethynyl-;6-ethynylpicolinaldehyde
• CAS NO: 183438-97-3
• Molecular Formula: C₈H₅NO
• Molecular Weight: 131.1314
• Product Categories: PYRIDINE
• Mol File: 183438-97-3.mol
• Article Data: 4

Chemical Properties

• Boiling Point: 237.1±25.0 °C(Predicted)
• Appearance: /
• Density: 1.15±0.1 g/cm3(Predicted)
• PKA: 1.92±0.10(Predicted)
• CAS DataBase Reference: 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI)(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI)(183438-97-3)
• EPA Substance Registry System: 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI)(183438-97-3)

Safety Data

• Hazardous Substances Data: 183438-97-3(Hazardous Substances Data)

Usage

General Description

2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI) is a chemical compound that is also known by its systematic name 6-ethynylpyridine-2-carbaldehyde. It is a yellow to brown liquid with a molecular formula of C8H5NO and a molecular weight of 131.13 g/mol. 2-Pyridinecarboxaldehyde, 6-ethynyl- (9CI) is commonly used in various chemical reactions and as an intermediate in the synthesis of pharmaceuticals, agrochemicals, and other organic compounds. It is known to have a strong and distinct odor and should be handled with caution due to its potential irritant and toxic properties. Additionally, its unique structure and functional groups make it an important building block in organic chemistry.

Synthetic route

6-(2-trimethylsilylethynyl)pyridin-2-carbaldehyde (183438-94-0) → 6-ethynylpyridine-2-carboxaldehyde (183438-97-3)

Conditions	Yield
With potassium carbonate	98%
With potassium carbonate	98%
With methanol; potassium carbonate at 20℃; for 1h;	83.4%
With potassium carbonate In methanol at 20℃; for 1h; Inert atmosphere;	83.4%

2,6-Dibromopyridine (626-05-1) → 6-ethynylpyridine-2-carboxaldehyde (183438-97-3)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: n-butyllithium / tetrahydrofuran; hexane 1.2: 78 percent / tetrahydrofuran; hexane 2.1: 95 percent / copper(I) iodide / tetrakis(triphenylphosphine)palladium(0) 3.1: 98 percent / potassium carbonate View Scheme
Multi-step reaction with 3 steps 1.1: BuLi / tetrahydrofuran; hexane 1.2: tetrahydrofuran; hexane 1.3: 78 percent / HCl / tetrahydrofuran; hexane 2.1: 95 percent / Pd(PPh3)4; CuI 3.1: 98 percent / K2CO3 View Scheme

6-bromo-2-pyridinecarbaldehyde (34160-40-2) → 6-ethynylpyridine-2-carboxaldehyde (183438-97-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: 95 percent / copper(I) iodide / tetrakis(triphenylphosphine)palladium(0) 2: 98 percent / potassium carbonate View Scheme
Multi-step reaction with 2 steps 1: 95 percent / Pd(PPh3)4; CuI 2: 98 percent / K2CO3 View Scheme
Multi-step reaction with 2 steps 1: bis-triphenylphosphine-palladium(II) chloride; triethylamine; copper(l) iodide / 20 °C / Inert atmosphere 2: potassium carbonate; methanol / 1 h / 20 °C View Scheme
Multi-step reaction with 2 steps 1: copper(l) iodide; trans-bis(triphenylphosphine)palladium dichloride; triethylamine / 20 °C / Inert atmosphere 2: potassium carbonate / methanol / 1 h / 20 °C / Inert atmosphere View Scheme

2-bromo-6-(4-hexyl-phenylethynyl)-pyridine (762262-22-6) + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → 2-formyl-6-[6-(4-hexylphenylethynyl)pyridin-2-ylethynyl]pyridine (804555-76-8)

Conditions	Yield
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) Sonogashira coupling;	74%
With copper(l) iodide; diisopropylamine; tetrakis(triphenylphosphine) palladium(0) In toluene at 40℃; for 12h; Sonogashira coupling;	74%

pentafluoro(4-iodophenyl)-λ6-sulfane (286947-68-0) + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → 6-((4-(pentafluorothio)phenyl)ethynyl)picolinaldehyde (1401165-57-8)

Conditions	Yield
With triethylamine; bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide In acetonitrile at 20 - 80℃; for 0.5h;	57%

4-(6-(3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazole[1,5-a]pyridine-3-carbonitrile dihydrochloride + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → 4-(6-(6-((6-ethynylpyridin-2-yl)methyl)-3,6-diazabicyclo[3.1.1]hept-3-yl)pyridin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

Conditions	Yield
With sodium tris(acetoxy)borohydride In 1,2-dichloro-ethane at 35℃;	48.93%

6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → C92H66N4

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 74 percent / Pd(PPh3)4; CuI 2.1: BuLi / tetrahydrofuran; hexane / 2 h / -78 °C 2.2: ClP(O)(OEt)2 / tetrahydrofuran; hexane / 2 h / 20 °C 2.3: 53 percent / lithium hexamethyldisilazide / tetrahydrofuran; hexane / 2 h / -78 - 20 °C View Scheme

pentafluoro(4-iodophenyl)-λ6-sulfane (286947-68-0) + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → (2R)-3-methyl-2-{[(6-{[4-(pentafluoro-λ6-sulfanyl)phenyl]ethynyl}pyridin-2-yl)methyl]amino}butan-1-ol

Conditions	Yield
Multi-step reaction with 2 steps 1: triethylamine / copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / acetonitrile / 0.5 h / 20 - 80 °C 2: acetic acid / MP-cyanoborohydride / dichloromethane; methanol / 20 °C View Scheme

formaldehyd (50-00-0) + N,N-diethyl-1,4-phenylenediamine dihydrochloride (2198-58-5, 16713-15-8, 84609-46-1) + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → 2-(4-(diethylamino)phenyl)-5-ethynyl-2H-imidazo[1,5-a]pyridin-4-ium chloride

Conditions	Yield
In ethanol at 20 - 25℃;

4-(6-(3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile dihydrochloride + 6-ethynylpyridine-2-carboxaldehyde (183438-97-3) → 4-(6-(6-((6-ethynylpyridin-2-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile

Conditions	Yield
With sodium tris(acetoxy)borohydride In 1,2-dichloro-ethane at 35℃; Inert atmosphere;

Upstream product

• 183438-94-0 6-(2-trimethylsilylethynyl)pyridin-2-carbaldehyde 
• 34160-40-2 6-bromo-2-pyridinecarbaldehyde 
• 626-05-1 2,6-Dibromopyridine 

Downstream Products

• 804555-76-8 2-formyl-6-[6-(4-hexylphenylethynyl)pyridin-2-ylethynyl]pyridine 
• 1401165-57-8 6-((4-(pentafluorothio)phenyl)ethynyl)picolinaldehyde 

Relevant articles and documents

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