2456-81-7

Basic information

• Product Name: 4-Pyrrolidinopyridine
• Synonyms: 1-(4-PYRIDYL)PYRROLIDINE;4-PYRROLIDIN-1-YL-PYRIDINE;4-PYRROLIDINOPYRIDINE;4-(1-PYRROLIDINO)PYRIDINE;4-(1-PYRROLIDINYL)PYRIDINE;TIMTEC-BB SBB004083;N-(4-PYRIDYL)PYRROLIDINE;4-(1-Pyrrolidyl) pyridine
• CAS NO: 2456-81-7
• Molecular Formula: C₉H₁₂N₂
• Molecular Weight: 148.2
• EINECS: 219-534-2
• Product Categories: Pyridine;Pyridines derivates;Pyridines;Condensation & Active Esterification;Synthetic Organic Chemistry;C9 to C46;Heterocyclic Building Blocks;Heterocycle-Pyridine series
• Mol File: 2456-81-7.mol
• Article Data: 17

Chemical Properties

• Melting Point: 54-58 °C(lit.)
• Boiling Point: 171-173 °C (20.2527 mmHg)
• Flash Point: >230 °F
• Appearance: White to yellow to light brown/Crystalline Mass, Crystals and/or Chunks
• Density: 1.0628 (rough estimate)
• Vapor Pressure: 0.0105mmHg at 25°C
• Refractive Index: 1.5378 (estimate)
• Storage Temp.: Store at RT.
• Solubility: methanol: 0.1 g/mL, clear
• PKA: 9.58±0.10(Predicted)
• Water Solubility: 3 g/L (21 ºC)
• BRN: 472443
• CAS DataBase Reference: 4-Pyrrolidinopyridine(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Pyrrolidinopyridine(2456-81-7)
• EPA Substance Registry System: 4-Pyrrolidinopyridine(2456-81-7)

Safety Data

• Hazard Codes: T
• Statements: 25-34-41-23/24/25
• Safety Statements: 26-36/37/39-45
• RIDADR: UN 2923 8/PG 3
• WGK Germany: 3
• F: 8-10-23
• HazardClass: 8
• PackingGroup: II
• Hazardous Substances Data: 2456-81-7(Hazardous Substances Data)

Usage

Description

4-Pyrrolidinopyridine is the pyridine derivative. It can be used as catalyst employed in polymerization reactions or Hypernucleophilic acylation catalyst. For example, it can be used as the catalyst for the geometry-selective (E-selective) acylation of tetrasubstituted α, α'-alkenediols. It can also be used as the ligand in metal complexes such as the Chloride and pseudohalide hydride-carbonyl ruthenium(II) complexes.

Chemical Properties

white to light brown crystalline mass

Uses

Catalyst employed in polymerization reactions. Ligand in metal complexes.

Synthesis Reference(s)

Synthetic Communications, 9, p. 251, 1979 DOI: 10.1080/00397917908064147Synthesis, p. 985, 1988 DOI: 10.1055/s-1988-27777

References

http://www.sigmaaldrich.com/catalog/product/aldrich/213373?lang=en®ion=US http://www.sigmaaldrich.com/catalog/product/sial/83275?lang=en®ion=US Yamanaka M et al. "Origin of High E -Selectivity in 4-Pyrrolidinopyridine-Catalyzed Tetrasubstituted α,α′-Alkenediol: A Computational and Experimental Study." Journal of Organic Chemistry 80.6(2015):3075-82. J. G. Ma?ecki, and A. Maroń. "Chloride and pseudohalide hydride-carbonyl ruthenium(II) complexes with 4-pyrrolidinopyridine as co-ligand."Transition Metal Chemistry 38.2(2013):133-142.

InChI:InChI=1/C9H12N2/c1-2-8-11(7-1)9-3-5-10-6-4-9/h3-6H,1-2,7-8H2/p+1

Synthetic route

pyrrolidine (123-75-1) + 4-chlorpyridine hydrochloride (7379-35-3) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
With sodium hydroxide; water In 1,4-dioxane at 70℃; under 6000480 Torr; for 20h; Substitution;	90%
With sodium hydride; 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazolium chloride; tert-butyl alcohol; bis(acetylacetonate)nickel(II) In tetrahydrofuran at 65℃; for 2.5h;	90%
In water at 130℃; for 0.5h; Microwave irradiation;	90%
With copper; caesium carbonate; methyl-alpha-D-glucopyranoside In water; dimethyl sulfoxide at 110℃; for 14h; Sealed tube; Green chemistry;	89%
at 130℃; for 0.5h; microwave irradiation;	85%

pyrrolidine (123-75-1) + 4-Chloropyridine (626-61-9) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
With zinc(II) nitrate hexahydrate In acetonitrile at 75℃; for 24h; Sealed tube; Green chemistry;	89%
With potassium phosphate; benzoin oxime; copper diacetate In dimethyl sulfoxide at 80℃; Inert atmosphere;	86%
at 130℃; for 0.5h; microwave irradiation;	85%

N-Pyridin-4-yl-succinamic acid methyl ester; hydrochloride (121409-81-2) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
With dimethylsulfide borane complex In tetrahydrofuran for 9h; Heating;	58%

pyrrolidine (123-75-1) + 3-Bromopyridine (626-55-1) → N-(pyridine-3-yl)pyrrolidine (69698-09-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
With sodium amide; sodium t-butanolate 1) THF, 40 deg C, 2 h 2) 40 deg C, 4.7 h; Yield given. Multistep reaction. Yields of byproduct given;

pyrrolidine (123-75-1) + 4-((trimethylsilyl)oxy)pyridine (27248-04-0) + N-trimethylsilylpyrrolidine (15097-49-1) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
With ammonium sulfate In pyridine at 150℃; for 15h; Yield given;

4-pyridone (108-96-3) + N-trimethylsilylpyrrolidine (15097-49-1) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In pyridine at 150 - 160℃; 1) 6 h; 12 h, 2) 40 h; Yield given;

pyrrolidine (123-75-1) + pyridine-4-carbonitrile (100-48-1) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
Stage #1: pyrrolidine With n-butyllithium In tetrahydrofuran; hexane at 0 - 20℃; for 0.25h; Stage #2: pyridine-4-carbonitrile With cesium fluoride In tetrahydrofuran; hexane at 65℃; for 2h; Further stages.;	80 % Chromat.

4-aminopyridine (504-24-5) → 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: 90 percent / diethyl ether; tetrahydrofuran / 1 h / Heating 2: 58 percent / 10M Me2S*BH3 / tetrahydrofuran / 9 h / Heating View Scheme

pyridin-4-ol (626-64-2) + phosphorus pentaoxide (337913-25-4) → 2-(Dimethylamino)pyridine (5683-33-0) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In dibutylamine
In dibutylamine

C33H49BrN2Si (1349883-23-3) → (E)-1,2-dibromo-1,2-bis(1,1,7,7-tetraethyl-3,3,5,5-tetramethyl-s-hydrindacen-4-yl)disilene (1349883-19-7) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In benzene-d6 at 25℃; Equilibrium constant;

C37H57BrN2Si (1349883-35-7) → (E)-1,2-dibromo-1,2-bis(1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl)-disilene (1187770-53-1) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In benzene-d6 at 25℃; Equilibrium constant;

C30H30N3(1+)*BF4(1-) → C21H18N(1+)*BF4(1-) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In dichloromethane at 20℃; Equilibrium constant;

C30H32N3(1+)*BF4(1-) → (4-dimethylaminophenyl)diphenylmethylium tetrafluoroborate (1995-50-2) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In dichloromethane at 20℃; Equilibrium constant;

C23H26IN2(1+)*CF3O3S(1-) → bis(4-methylphenyl)iodonium trifluoromethanesulfonate (123726-16-9) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H20Br2IN2(1+)*CF3O3S(1-) → 4-pyrrolidin-1-ylpyridine (2456-81-7) + bis(4-bromophenyl)iodonium triflate (139139-81-4)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H20F2IN2(1+)*CF3O3S(1-) → bis(4-fluorophenyl)iodonium triflate (732306-64-8) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C18H22ClIO6 → C15H16IO3(1+)*F6P(1-) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H20IN2(1+)*CF3O3S(1-) → [1,1'-biphenyl]-2,2'-iodonium trifluoromethanesulfonate (189999-35-7) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H22IN2(1+)*CF3O3S(1-) → Diphenyliodonium triflate (66003-76-7) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C22H21F3IN2(1+)*CF3O3S(1-) → (3-trifluoromethylphenyl)(phenyl)iodonium triflate + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C23H20F6IN2(1+)*F6P(1-) → (3,5-bis(trifluoromethyl)phenyl)(phenyl)iodonium hexafluorophosphate + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H17F5IN2(1+)*F6P(1-) → (perfluorophenyl)(phenyl)iodonium hexafluorophosphate (951037-67-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C21H21IN3O2(1+)*CF3O3S(1-) → [(4-nitrophenyl)(phenyl)iodonium trifluoromethanesulfonate] (905718-45-8) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

C24H27IN3O2(1+)*CF3O3S(1-) → (4-nitrophenyl)(2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate (1146127-11-8) + 4-pyrrolidin-1-ylpyridine (2456-81-7)

Conditions	Yield
In acetonitrile at 20℃; Equilibrium constant; Inert atmosphere;

2,4,6-trichloropyrimidine (3764-01-0) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 1,1',1''-(pyrimidin-2,4,6-triyl)-tris-4-(pyrrolidin-1-yl)pyridinium tri-iodide

Conditions	Yield
With sodium iodide In acetone Ambient temperature;	100%

4-pyrrolidin-1-ylpyridine (2456-81-7) + 2-amino-6-chloro-4-pyrimidinol (1194-21-4) → 1-(2-amino-6-oxo-1,6-diydropyrimidin-4-yl)-4-(pyrrolidin-1-yl)pyridinium chloride

Conditions	Yield
In 1,2-dichloro-benzene for 0.5h; Heating;	100%

2,3,4,5,6-pentachloropyridine (2176-62-7) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 1,1',1''-tris[4-pyrrolidino-(3,5-dichloropyridine-2,4,6-triyl)-pyridinium] trichloride

Conditions	Yield
In N,N-dimethyl-formamide at 120℃; for 2h;	100%

(4R,6R)-6-{2[(1S,2S,6S,8S,8AR)-1,2,6,7,8,8a-hexahydro-6-t-butyldimethylsilyloxy-8-hydroxy-2-methyl-1-naphthyl]ethyl}-tetrahydro-4-t-butyldimethylsilyloxy-2H-pyran-2-one + 2-ethyl-2-methylbutyryl chloride (60545-29-1) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (4R,6R)-6-{2-[(1S,2S,6S,8S,8aR)-1,2,6,7,8,8a-hexahydro-6-t-butyldimethylsilyloxy-8-(2-ethyl-2-methylbutyryloxy)-2-methyl-1-naphthyl]ethyl}tetrahydro-4-t-butyldimethylsilyloxy-2H-pyran-2-one (159224-70-1)

Conditions	Yield
With sodium chloride; sodium hydrogencarbonate; triethylamine; citric acid In hexane; water; ethyl acetate; benzene	100%

4-pyrrolidin-1-ylpyridine (2456-81-7) + 1-Iodohexane (638-45-9) → 1-n-hexyl-4-pyrorridinopyridinium iodide (1220834-53-6)

Conditions	Yield
at 120℃; for 16h;	100%

2,3,5,6-tetrachloropyridine (2402-79-1) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 1,1'-bis[4-pyrrolidino-(3,5-dichloro-pyridine-2,6-diyl)pyridinium]dichloride

Conditions	Yield
In N,N-dimethyl-formamide at 120℃; for 3h;	99%

4-pyrrolidin-1-ylpyridine (2456-81-7) → 4-(pyrrolidin-1-yl)pyridine borane complex (1260245-71-3)

Conditions	Yield
With borane-THF In toluene for 2h; Cooling with ice;	97%

C66H82Br2N6O7Zn + 4-pyrrolidin-1-ylpyridine (2456-81-7) → C75H92Br2N8O6Zn

Conditions	Yield
In dichloromethane for 0.00833333h;	97%

4-pyrrolidin-1-ylpyridine (2456-81-7) → C9H10(2)H2N2

Conditions	Yield
With water-d2; hydrogen chloride at 190℃; for 2h; Microwave irradiation;	97%

pyridin-2-yl trifluoromethanesulfonate (65007-00-3) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → C14H16N3(1+)*CF3O3S(1-)

Conditions	Yield
at 150 - 180℃; Inert atmosphere;	97%

4-pyrrolidin-1-ylpyridine (2456-81-7) + saccharin (81-07-2) → 4-(1-pyrrolidinyl)pyridinium saccharinate

Conditions	Yield
In tetrahydrofuran at 60℃; for 12h; Inert atmosphere;	96.7%
In tetrahydrofuran at 60℃;	95%

4-pyrrolidin-1-ylpyridine (2456-81-7) + Propiolic acid (471-25-0) → 4-(Pyrrolidino)-pyridinium propynoate

Conditions	Yield
In ethanol at 25℃; for 30h;	96.2%

4-pyrrolidin-1-ylpyridine (2456-81-7) → C9H8(2)H4N2 (121697-81-2)

Conditions	Yield
With water-d2 at 190℃; for 2h; Microwave irradiation;	96%
With water-d2 at 260℃; for 24h; in a sealed glass tube;

4-pyrrolidin-1-ylpyridine (2456-81-7) + 2-propynyl chloride (624-65-7) → 1-Prop-2-ynyl-4-pyrrolidin-1-yl-pyridinium; perchlorate

Conditions	Yield
In dichloromethane for 0.5h; Ambient temperature;	95%

2,3,4,5,6-pentachloropyridine (2176-62-7) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 1-(4-pyrrolidino)-[2,3,5,6-tetrachloropyridin-4-yl]-pyridinium chloride

Conditions	Yield
In 1,2-dichloro-benzene at 20℃; for 24h;	95%

4-pyrrolidin-1-ylpyridine (2456-81-7) + saccharin (81-07-2) → 4‐(1‐pyrrolidinyl)pyridinium saccharinate

Conditions	Yield
In tetrahydrofuran at 60℃;	95%

p-phenylbenzyl bromide (2567-29-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 1-([1,1'-biphenyl]-4-ylmethyl)-4-(pyrrolidin-1-yl)pyridin-1-ium bromide

Conditions	Yield
at 140℃; Sealed tube; Microwave irradiation;	94%

1,3,5-Tris(bromomethyl)benzene (18226-42-1) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → C36H45N6(3+)*3Br(1-)

Conditions	Yield
In butanone at 100℃; for 192h;	93%

tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidine][benzylidene]ruthenium(II) dichloride (246047-72-3) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (IMesH2)(C9H12N2)2(Cl)2Ru=CHP

Conditions	Yield
at 20 - 25℃; for 12h;	93%

bis(pentamethylcyclopentadienyl)dizinc (849926-75-6, 773895-85-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (η5-C5Me5)Zn2(4-pyrrolidinopyridine)2(η5-C5Me5)

Conditions	Yield
In diethyl ether (under Ar, Schlenk); soln. of ligand in Et2O added slowly to soln. of Zn-complex in Et2O at -10°C, reacted at room temp. and stirred for 30 min; solvent evapd. under reduced pressure, pentane added at -20°C, filtered, washed with pentane, dried under vac.;	93%

3,5-bistrifluoromethylphenylisothiocyanate (23165-29-9) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (Z)-N-[3,5-bis(trifluoromethyl)phenyl]-4-(pyrrolidinium-1-ylidene)pyridine-1(4H)-carbimidothioate (1027640-50-1)

Conditions	Yield
In toluene at 20℃;	92%

4-pyrrolidin-1-ylpyridine (2456-81-7) + methyl iodide (74-88-4) → 1-methyl-4-(pyrrolidin-1-yl)pyridin-1-ium iodide

Conditions	Yield
In ethanol for 5h; Reflux;	92%
In acetonitrile at 20℃; for 2h;	87%
In ethanol; water-d2

dimethylsulfide borane complex (13292-87-0) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → 4-(pyrrolidin-1-yl)pyridine borane complex (1260245-71-3)

Conditions	Yield
In toluene at 0 - 20℃; for 2.5h; Inert atmosphere; Schlenk technique;	91%

(4R,6R)-6-{2[(1S,2S,6S,8S,8AR)-1,2,6,7,8,8a-hexahydro-6-t-butyldimethylsilyloxy-8-hydroxy-2-methyl-1-naphthyl]ethyl}-tetrahydro-4-t-butyldimethylsilyloxy-2H-pyran-2-one + 2,2-diethylbutanoyl chloride (35354-15-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (4R,6R)-6-{2-[(1S,2S,6S,8S,8aR)-1,2,6,7,8,8a-Hexahydro-6-t-butyldimethylsilyloxy-8-(2,2-diethylbutyryloxy)-2-methyl-1-naphthyl]ethyl}tetrahydro-4-t-butyldimethylsilyloxyl-2H-pyran-2-one (159224-71-2)

Conditions	Yield
With triethylamine In toluene	89%

4-pyrrolidin-1-ylpyridine (2456-81-7) + 1-iodo-propane (107-08-4) → 1-propyl-4-(pyrrolidin-1-yl)pyridin-1-ium iodide

Conditions	Yield
In ethanol for 5h; Reflux;	89%
In ethanol; water-d2

(4R,6R)-6-{2[(1S,2S,6S,8S,8AR)-1,2,6,7,8,8a-hexahydro-6-t-butyldimethylsilyloxy-8-hydroxy-2-methyl-1-naphthyl]ethyl}-tetrahydro-4-t-butyldimethylsilyloxy-2H-pyran-2-one + 2-ethylbutyric anhydride (54502-37-3) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → (4R,6R)-6-{2-[(1S,2S,6S,8S,8AR)-1,2,6,7,8,8a-Hexahydro-6-t-butyldimethylsilyloxy-8-(2-ethylbutyryloxy)-2-methyl-1-naphthyl]ethyl)tetrahydro-4-t-butyldimethylsilyloxy-2H-pyran-2-one

Conditions	Yield
With sodium chloride; sodium hydrogencarbonate; triethylamine; citric acid In dichloromethane; water; ethyl acetate	88%

water (7732-18-5) + 4-pyrrolidin-1-ylpyridine (2456-81-7) + silver nitrate → [Ag(4-(pyrrolidin-1-yl)pyridine)2]NO3*1/2H2O

Conditions	Yield
In ethanol	88%

1-bromo-hexane (111-25-1) + 4-pyrrolidin-1-ylpyridine (2456-81-7) → C15H25N2(1+)*Br(1-)

Conditions	Yield
In acetonitrile at 80℃; for 12h; Inert atmosphere;	88%
In acetonitrile at 80℃; for 12h; Inert atmosphere;	88%

Upstream product

• 1349883-35-7 C₃₇H₅₇BrN₂Si 
• 1349883-23-3 C₃₃H₄₉BrN₂Si 
• 626-64-2 pyridin-4-ol 
• 337913-25-4 phosphorus pentaoxide 
• 504-24-5 4-aminopyridine 
• 123-75-1 pyrrolidine 
• 100-48-1 pyridine-4-carbonitrile 
• 626-61-9 4-Chloropyridine 
• 7379-35-3 4-chlorpyridine hydrochloride 
• 121409-81-2 N-Pyridin-4-yl-succinamic acid methyl ester; hydrochloride 
• 108-96-3 4-pyridone 

Downstream Products

• 24544-04-5 2,6-diisopropylbenzenamine 
• 121919-39-9 Ti(O)(2,6-diisopropylphenoxide)2(4-pyrrolidinopyridine)2 
• 129345-15-9 (η2-azobenzene){bis(4-pyrrolidinopyridine)}{(2,6-iPr2-C6H3O)2}titanium 

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