971-66-4

Basic information

• Product Name: Pyridine-triphenylborane
• Synonyms: PYRIDINE-TRIPHENYLBORANE COMPLEX;Pyridine-triphenylborane;Pyridine-triPhenylborate;Pyridine-triphenylborane(1/1);Pyridine-triphenylbo;Triphenyl(pyridin-1-iuM-1-yl)borate;Boron,triphenyl(pyridine)-, (T-4)-;Triphenyl borane,pyridine complex
• CAS NO: 971-66-4
• Molecular Formula: C₂₃H₂₀BN
• Molecular Weight: 321.22
• Mol File: 971-66-4.mol
• Article Data: 9

Chemical Properties

• Melting Point: 214-215 °C (decomp)
• Boiling Point: 348 °C at 760 mmHg
• Flash Point: 161.1 °C
• Appearance: /
• Vapor Pressure: 0.000104mmHg at 25°C
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• CAS DataBase Reference: Pyridine-triphenylborane(CAS DataBase Reference)
• NIST Chemistry Reference: Pyridine-triphenylborane(971-66-4)
• EPA Substance Registry System: Pyridine-triphenylborane(971-66-4)

Safety Data

• Hazardous Substances Data: 971-66-4(Hazardous Substances Data)

Usage

InChI:InChI=1/C18H15B.C5H5N/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18;1-2-4-6-5-3-1/h1-15H;1-5H

Synthetic route

sodium tetraphenyl borate (143-66-8) + copper(ll) bromide (7789-45-9) → triphenylborane pyridine complex (971-66-4) + tetraphenyl-boric acid ; copper (I)-salt (14637-33-3)

Conditions

Yield

With pyridine In 1,2-dimethoxyethane byproducts: NaBr, biphenyl; CuBr2 added to NaBPh4 soln.; mixt. stirred at 25°C for 48 h; DME removed in vac.; residue extd. under N2 with hexane and diethyl ether; pyridine added to combined extracts; Ph3B*pyridine ppt. filtered and recrystd.; identified by m.p. and IR spectrum; filtrate evapd. to give biphenyl; further extn. of reactn. residue by THF; ext. evapd. under N2 to give CuBPh4;

A 95% B 85%

bis(η5-1,2,4-tri-tert-butylcyclopentadienyl)U(O)(pyridine) (863607-63-0) + triphenylborane (960-71-4) → triphenylborane pyridine complex (971-66-4) + bis(1,2,4-tri-tert-butylcyclopentadienyl)uranium oxide (863607-65-2)

Conditions	Yield
In toluene (N2); addn. of a soln. of boron compd. in toluene to a soln. of uranium complex in toluene at room temp., stirring for 2 h; rvapn., extn. with pentane, filtration, concn., cooling to -20°C,filtration; elem. anal.;	A n/a B 83%

pyridine (110-86-1) + bromobenzene (108-86-1) + boron trifluoride diethyl etherate (109-63-7) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
Stage #1: bromobenzene; boron trifluoride diethyl etherate With magnesium In tetrahydrofuran Inert atmosphere; Reflux; Stage #2: pyridine In tetrahydrofuran at 40℃; for 3h; Inert atmosphere;	75%

borane (13283-31-3) + triphenyltin chloride (639-58-7) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
With pyridine; water In tetrahydrofuran; diethyl ether to Sn compd. in THF added BH3 (B/Sn ratio 1/1) under N2 at room temp., stirred for 1 h, refluxed for 1h, cooled to room temp., added H2O, stirred for 30 min at room temp, extd. with Et2O, dried (MgSO4), heated with pentane, evapd., added Et2O and C5H5N;	70%

(2,2,6,6-tetramethylpiperidino)2AlI(pyridine) (211381-81-6) + silver tetraphenylborate (14637-35-5) → triphenylborane pyridine complex (971-66-4) + bis(2,2,6,6-tetramethylpiperidino)phenylaluminium

Conditions	Yield
In benzene byproducts: AgI; inert atmosphere, addn. of soln. of Al complex to suspension of borate at room temp., reflux (3 d); filtration, removement of volatiles (vacuum), extn. (toluene), crystn. (-78°C, overnight); elem. anal.;	A 39% B n/a
In toluene byproducts: AgI; inert atmosphere, addn. of soln. of Al complex to suspension of borate at room temp., reflux (3 d); filtration, removement of volatiles (vacuum), extn. (toluene)crystn. (-78°C, overnight);

pyridine (110-86-1) + triphenylborane (960-71-4) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
In chloroform at 65℃; for 1h; Inert atmosphere;	30%
at 20℃; Equilibrium constant; Inert atmosphere;

pyridine (110-86-1) + sodium hydroxide adduct of triphenylboron → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
In water at 20 - 45℃; for 0.5 - 1h;

(2,2,6,6-tetramethylpiperidino)2AlI(pyridine) (211381-81-6) + sodium tetraphenyl borate (143-66-8) → triphenylborane pyridine complex (971-66-4) + bis(2,2,6,6-tetramethylpiperidino)phenylaluminium

Conditions	Yield
In toluene byproducts: AgI; inert atmosphere, addn. of soln. of Al complex to suspension of borate at room temp., 110°C (3 d); filtration, removement of volatiles (vacuum), extn. (toluene)crystn. (-78°C, overnight);

sodium tetraphenyl borate (143-66-8) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
With pyridine In 1,2-dimethoxyethane byproducts: C6H6; Irradiation (UV/VIS); under N2; photolysis; treating photolysate soln. with pyridine; Ph3B*pyridine was isolated;

triphenylborane (960-71-4) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
With pyridine In diethyl ether recrystn. from warm pyridine/ether;
With pyridine In diethyl ether to soln. of BPh3 in Et2O added 1 equiv of pyridine under N2;

pyridine (110-86-1) → triphenylborane pyridine complex (971-66-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: hexane 2: benzene View Scheme
Multi-step reaction with 2 steps 1: hexane 2: toluene View Scheme

triphenylborane (960-71-4) + C39H49Cl2N3Ru → triphenylborane pyridine complex (971-66-4) + C68H88Cl4N4Ru2

Conditions	Yield
In dichloromethane-d2 at 25℃; Equilibrium constant; Inert atmosphere; Sealed tube;

dichloro(N,N'-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene)(pyridine)ruthenium(II) + triphenylborane (960-71-4) → triphenylborane pyridine complex (971-66-4) + C56H64Cl4N4Ru2

Conditions	Yield
In dichloromethane-d2 at -10℃; Equilibrium constant; Inert atmosphere; Sealed tube;

triphenylborane pyridine complex (971-66-4) + tetrabutylammomium bromide (1643-19-2) + 4-methoxyphenylacetylen (768-60-5) → tetrabutylammonium [(4-methoxyphenyl)ethynyl]triphenylborate

Conditions	Yield
Stage #1: 4-methoxyphenylacetylen With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1.5h; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran; hexane at -78 - 20℃; for 1h; Inert atmosphere; Stage #3: tetrabutylammomium bromide In methanol Inert atmosphere;	96%

triphenylborane pyridine complex (971-66-4) + m-iodonitrobenzene (645-00-1) → 3-nitro-1,1'-biphenyl (2113-58-8)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 4h; Suzuki-Miyaura Coupling; Inert atmosphere;	95%

triphenylborane pyridine complex (971-66-4) + 1-Chloro-4-iodobenzene (637-87-6) → 4'-biphenyl chloride (2051-62-9)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	95%

triphenylborane pyridine complex (971-66-4) + 4-fluoro-1-iodobenzene (352-34-1) → 4-fluoro-biphenyl (324-74-3)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	95%

triphenylborane pyridine complex (971-66-4) + tetramethlyammonium chloride (75-57-0) + propargyl alcohol methyl ether (627-41-8) → tetramethylammonium (methoxymethylethynyl)triphenylborate (1160604-78-3)

Conditions	Yield
Stage #1: propargyl alcohol methyl ether With n-butyllithium In tetrahydrofuran at -78℃; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran at 20℃; for 1h; Stage #3: tetramethlyammonium chloride In methanol	92%

triphenylborane pyridine complex (971-66-4) + 4-tolyl iodide (624-31-7) → 4-Methylbiphenyl (644-08-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 4h; Suzuki-Miyaura Coupling; Inert atmosphere;	91%

2-ethynylpyridine (1945-84-2) + triphenylborane pyridine complex (971-66-4) + tetramethlyammonium chloride (75-57-0) → tetramethylammonium triphenyl(2-pyridinylethynyl)borate (1160605-01-5)

Conditions	Yield
Stage #1: 2-ethynylpyridine With n-butyllithium In tetrahydrofuran at -78℃; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran at 20℃; Stage #3: tetramethlyammonium chloride In methanol	89%

triphenylborane pyridine complex (971-66-4) + iodobenzene (591-50-4) → biphenyl (92-52-4)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 4h; Suzuki-Miyaura Coupling; Inert atmosphere;	88%

triphenylborane pyridine complex (971-66-4) + 4-Iodoacetophenone (13329-40-3) → biphenyl-4-acetaldehyde (92-91-1)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	88%

triphenylborane pyridine complex (971-66-4) + para-iodoanisole (696-62-8) → 4-methoxylbiphenyl (613-37-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Reagent/catalyst; Solvent; Temperature; Suzuki-Miyaura Coupling; Inert atmosphere;	87%

triphenylborane pyridine complex (971-66-4) + para-diiodobenzene (624-38-4) → [1,1';4',1'']terphenyl (92-94-4)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	87%

bromobenzene (108-86-1) + triphenylborane pyridine complex (971-66-4) → biphenyl (92-52-4)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	87%

triphenylborane pyridine complex (971-66-4) + 1-Bromo-4-fluorobenzene (460-00-4) → 4-fluoro-biphenyl (324-74-3)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	87%

triphenylborane pyridine complex (971-66-4) + 4-iodoanisol (529-28-2) → 2-methoxy-1,1'-biphenyl (86-26-0)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	84%

triphenylborane pyridine complex (971-66-4) + 3-methoxy-1-iodobenzene (766-85-8) → 3-methoxybiphenyl (2113-56-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 8h; Suzuki-Miyaura Coupling; Inert atmosphere;	83%

1-bromo-4-methoxy-benzene (104-92-7) + triphenylborane pyridine complex (971-66-4) → 4-methoxylbiphenyl (613-37-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	82%

triphenylborane pyridine complex (971-66-4) + p-trifluoromethylphenyl bromide (402-43-7) → 1-phenyl-4-(trifluoromethyl)benzene (398-36-7)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	80%

triphenylborane pyridine complex (971-66-4) + m-trifluoromethylphenyl iodide (401-81-0) → 3-(trifluoromethyl)biphenyl (366-04-1)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 50℃; for 4h; Suzuki-Miyaura Coupling; Inert atmosphere;	79%

triphenylborane pyridine complex (971-66-4) + 4-Phenyl-1-butyne (16520-62-0) + tetramethylammonium halide → tetramethylammonium triphenyl(4-phenylbut-1-ynyl)borate

Conditions	Yield
Stage #1: 4-Phenyl-1-butyne With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1.5h; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran; hexane at -78 - 20℃; for 1h; Inert atmosphere; Stage #3: tetramethylammonium halide In methanol Inert atmosphere;	78%

triphenylborane pyridine complex (971-66-4) + 1-chloro-2-fluorobenzene (348-51-6) → 2-fluorobiphenyl (321-60-8)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	77%

triphenylborane pyridine complex (971-66-4) + 4-methoxyphenylacetylen (768-60-5) → 4-(phenylethynyl)anisole (7380-78-1)

Conditions	Yield
Stage #1: 4-methoxyphenylacetylen With n-butyllithium In tetrahydrofuran; hexane at 20℃; for 1.5h; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran; hexane at 20℃; for 1h; Inert atmosphere; Stage #3: With oxovanadium(V) ethoxydichloride In dichloromethane; acetonitrile at 20℃; for 2h; Inert atmosphere;	76%

triphenylborane pyridine complex (971-66-4) + para-bromotoluene (106-38-7) → 4-Methylbiphenyl (644-08-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	73%

triphenylborane pyridine complex (971-66-4) + 2-bromo-1-chlorobenzene (694-80-4) → 2-chloro-1,1'-biphenyl (2051-60-7)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	71%

3-Bromothiophene (872-31-1) + triphenylborane pyridine complex (971-66-4) → 3-phenylthiophene (2404-87-7)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	70%

triphenylborane pyridine complex (971-66-4) + n-octyne (629-05-0) + tetramethylammonium halide → tetramethylammonium oct-1-ynyltriphenylborate

Conditions	Yield
Stage #1: n-octyne With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1.5h; Inert atmosphere; Stage #2: triphenylborane pyridine complex In tetrahydrofuran; hexane at -78 - 20℃; for 1h; Inert atmosphere; Stage #3: tetramethylammonium halide In methanol Inert atmosphere;	69%

triphenylborane pyridine complex (971-66-4) + 3-methoxyphenyl bromide (2398-37-0) → 3-methoxybiphenyl (2113-56-6)

Conditions	Yield
With palladium diacetate; caesium carbonate In N,N-dimethyl-formamide at 80℃; for 12h; Suzuki-Miyaura Coupling; Inert atmosphere;	65%

Upstream product

• 110-86-1 pyridine 
• 211381-81-6 (2,2,6,6-tetramethylpiperidino)2AlI(pyridine) 
• 143-66-8 sodium tetraphenyl borate 
• 14637-35-5 silver tetraphenylborate 
• 7789-45-9 copper(ll) bromide 
• 13283-31-3 borane 
• 639-58-7 triphenyltin chloride 
• 960-71-4 triphenylborane 
• 863607-63-0 bis(η5-1,2,4-tri-tert-butylcyclopentadienyl)U(O)(pyridine) 
• 108-86-1 bromobenzene 
• 109-63-7 boron trifluoride diethyl etherate 

Downstream Products

• 12775-96-1 copper 
• 92-52-4 biphenyl 
• 92-94-4 [1,1';4',1'']terphenyl 
• 71-36-3 butan-1-ol 
• 7380-78-1 4-(phenylethynyl)anisole 
• 1160604-78-3 tetramethylammonium (methoxymethylethynyl)triphenylborate 
• 1160605-01-5 tetramethylammonium triphenyl(2-pyridinylethynyl)borate 
• 1160604-84-1 tetramethylammonium triphenylethynylborate 
• 1309647-76-4 C₂₅H₂₀BNO 
• 1309647-77-5 C₂₆H₂₂BNO₂ 
• 1309647-78-6 C₂₆H₁₉BF₃NO 
• 1309647-79-7 C₂₉H₂₂BNO 
• 1309647-80-0 C₂₆H₂₂BNO₂ 
• 1309647-81-1 C₂₆H₂₂BNO 

Relevant articles and documents

Lewis Acidic Boranes, Lewis Bases, and Equilibrium Constants: A Reliable Scaffold for a Quantitative Lewis Acidity/Basicity Scale

A quantitative Lewis acidity/basicity scale toward boron-centered Lewis acids has been developed based on a set of 90 experimental equilibrium constants for the reactions of triarylboranes with various O-, N-, S-, and P-centered Lewis bases in dichloromethane at 20 °C. Analysis with the linear free energy relationship log KB=LAB+LBB allows equilibrium constants, KB, to be calculated for any type of borane/Lewis base combination through the sum of two descriptors, one for Lewis acidity (LAB) and one for Lewis basicity (LBB). The resulting Lewis acidity/basicity scale is independent of fixed reference acids/bases and valid for various types of trivalent boron-centered Lewis acids. It is demonstrated that the newly developed Lewis acidity/basicity scale is easily extendable through linear relationships with quantum-chemically calculated or common physical–organic descriptors and known thermodynamic data (ΔH (Formula presented.)). Furthermore, this experimental platform can be utilized for the rational development of borane-catalyzed reactions.

Palladium-catalyzed suzuki-miyaura type coupling reaction of aryl halides with triphenylborane-pyridine

The Suzuki-Miyaura type coupling reaction of aryl halides with triphenylborane-pyridine was described. The reaction can be catalyzed by Pd(OAc)2 (5 mol%) in presence of Cs2CO3 at 50°C or 80°C, and functionalized biaryls were obtained in good to excellent yields. This protocol is general and can tolerate a wide range of functional groups. The Suzuki-Miyaura type coupling reaction of aryl halides with triphenylborane-pyridine was described. The reaction can be catalyzed by Pd(OAc)2 (5 mol%) in the presence of Cs2CO3 at 50°C or 80°C, and functionalized biaryls were obtained in good to excellent yields. This protocol is general and can tolerate a wide range of functional groups. Copyright

Process for making solid triphenylboron-pyridine or its adduct

A process for producing solid triphenylboron-pyridine (TPBP) spherical particles by separately feeding into a vigorously agitated reaction zone (i) a stream of pyridine and a (ii) stream comprising a solution of sodium hydroxide adduct of triphenylboron (TPBA) whereby the total concentration of TPBA in the combined feed streams is in the range of from 1 wt % to 6 wt %, and simultaneously removing a product stream from said reaction zone and recovering the triphenylboron-pyridine (TPBP) particles.