144025-03-6

Basic information

• Product Name: 2,4-Difluorophenylboronic acid
• Synonyms: B-(2,4-Difluorophenyl)boronic acid;RARECHEM AH PB 0168;2,4-DIFLUOROBENZENEBORONIC ACID;2,4-DIFLUOROPHENYLBORONIC ACID;2,4-FLUOROBENZENE BORONIC ACID;AKOS BRN-0089;2,4-Difluorophenylboric acid;2,4-difluorophenylboroic acid
• CAS NO: 144025-03-6
• Molecular Formula: C₆H₅BF₂O₂
• Molecular Weight: 157.91
• EINECS: -0
• Product Categories: blocks;BoronicAcids;FluoroCompounds;Boric Acid;Substituted Boronic Acids;Fluorobenzene;Boronic Acid;Aryl;Halogenated;Organoborons;B (Classes of Boron Compounds);Boronic Acids;Boronic Acids;Boronic Acids and Derivatives;6
• Mol File: 144025-03-6.mol
• Article Data: 8

Chemical Properties

• Melting Point: 247-250 °C
• Boiling Point: 251 ºC at 760 mmHg
• Flash Point: 105.6 ºC
• Appearance: Off-white to light beige or yellow/Powder
• Density: 1.35 g/cm³
• Vapor Pressure: 1.14mmHg at 25°C
• Storage Temp.: 0-6°C
• Solubility: Chloroform (Slightly, Sonicated), DMSO (Slightly), Methanol (Slightly)
• PKA: 8.47±0.58(Predicted)
• BRN: 8616257
• CAS DataBase Reference: 2,4-Difluorophenylboronic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2,4-Difluorophenylboronic acid(144025-03-6)
• EPA Substance Registry System: 2,4-Difluorophenylboronic acid(144025-03-6)

Safety Data

• Hazard Codes: Xn,Xi
• Statements: 36/37/38-22
• Safety Statements: 37/39-26-36
• WGK Germany: 3
• Hazardous Substances Data: 144025-03-6(Hazardous Substances Data)

Usage

Chemical Properties

off-white to light beige or yellow powder

Uses

Different sources of media describe the Uses of 144025-03-6 differently. You can refer to the following data:
1. suzuki reaction
2. 2,4-Difluorophenylboronic Acid is used as a reagent in suzuki-miyaura coupling reactions such as in the synthesis of enantiomerically pure 3,3''-bis-arylated BINOL derivatives. Also used in the synthesis of highly efficient phospherescent iridium (III) complexes which are used for light-emiiting diodes.

InChI:InChI=1/3CHF3O3S.Sc/c3*2-1(3,4)8(5,6)7;/h3*(H,5,6,7);/q;;;+3/p-3

Synthetic route

Trimethyl borate (121-43-7) + (2,4-difluorophenyl)magnesium bromide (144025-04-7) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
With sulfuric acid In tetrahydrofuran; water	84.3%
With sulfuric acid In tetrahydrofuran; water	84.3%
In tetrahydrofuran	74.8%
In tetrahydrofuran	74.8%
Stage #1: Trimethyl borate; (2,4-difluorophenyl)magnesium bromide In tetrahydrofuran at -60℃; for 5h; Stage #2: With hydrogenchloride In tetrahydrofuran; water at 0℃; pH=1; Inert atmosphere;	40%

2,4-difluorobromobenzene (348-57-2) + Trimethyl borate (121-43-7) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions

Yield

With n-butyllithium In diethyl ether; hexane n-BuLi (2.5 M, hexane) was added to C6F2BrH3 in Et2O at -70 °C, 1.5 equiv. of cold soln. of B(OMe)3 was added in Et2O, stirring at -60 °C for 1 h, mixt. was allowed to warm to 15 °C within 1 h; poured into 5 % HCl, org. layer was sepd., aq. layer was twice extd. with ether, extracts were combined, dried with MgSO4, evapn., solid was stored over water at 15 °C for 1 month;

77%

C6H3BF5(1-) (871300-65-1) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
In phosphate buffer pH=6.9 - 7.0; Kinetics;

tris(2,4-difluorophenyl)boroxine (512198-16-2) + water (7732-18-5) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
In acetonitrile
In diethyl ether

2-methoxy-ethanol (109-86-4) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
With sodium carbonate In water; acetylacetone

diisopropyl 2,4-difluorophenylboronate → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
With hydrogenchloride In water	1.15 g

2,4-difluorobromobenzene (348-57-2) + tri-n-propyl borate (688-71-1) + water (7732-18-5) → 2,4-difluorophenylboronic acid (144025-03-6)

Conditions	Yield
Stage #1: 2,4-difluorobromobenzene With magnesium Stage #2: tri-n-propyl borate Stage #3: water Acidic conditions;

2,4-difluorophenylboronic acid (144025-03-6) + 3-Iodobenzoic acid (618-51-9) → 2',4'-difluoro-[1,1'-biphenyl]-3-carboxylic acid

Conditions

Yield

Stage #1: 3-Iodobenzoic acid With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine; Wang resin In dichloromethane at 20℃; for 22h; Stage #2: 2,4-difluorophenylboronic acid With tris(dibenzylideneacetone)dipalladium (0); potassium carbonate In N,N-dimethyl-formamide at 20℃; Stage #3: With trifluoroacetic acid In dichloromethane at 20℃; for 13h;

100%

2-bromo-pyridine (109-04-6) + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenyl)pyridine (391604-55-0)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In tetrahydrofuran at 70℃; for 24h; Suzuki coupling;	100%
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In tetrahydrofuran; water at 70℃; Inert atmosphere;	98%
With sodium carbonate; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran; water at 70℃; for 24h;	97%

trifluoromethanesulfonic acid 6-methoxy-1-[4-(2-piperidin-1-ylethoxy)phenoxy]naphthalen-2-yl ester (648904-46-5) + 2,4-difluorophenylboronic acid (144025-03-6) → 1-(2-{4-[2-(2,4-difluoro-phenyl)-6-methoxy-naphthalen-1-yloxy]-phenoxy}-ethyl)-piperidine hydrochloride

Conditions	Yield
Stage #1: trifluoromethanesulfonic acid 6-methoxy-1-[4-(2-piperidin-1-ylethoxy)phenoxy]naphthalen-2-yl ester; 2,4-difluorophenylboronic acid With cesium fluoride; tricyclohexylphosphine; palladium diacetate In acetonitrile at 90℃; for 0.166667h; Suzuki Coupling; Stage #2: With hydrogenchloride In diethyl ether	100%

4-Iodophenol (540-38-5) + 2,4-difluorophenylboronic acid (144025-03-6) → 4-(2,4-difluorophenyl)-phenol (59089-68-8)

Conditions	Yield
With potassium carbonate; palladium(0)bis(tricyclohexylphosphine) In water; N,N-dimethyl-formamide Inert atmosphere; Reflux;	100%

(6-Bromopyridin-2-yl)-[5-(2-tert-butyl-pyrimidin-4-yl)-2-methylphenyl]amine (1380281-66-2) + 2,4-difluorophenylboronic acid (144025-03-6) → [5-(2-tert-Butyl-pyrimidin-4-yl)-2-methylphenyl]-[6-(2,4-difluorophenyl)-pyridin-2-yl]amine (1380281-67-3)

Conditions	Yield
With sodium carbonate; tetrakis(triphenylphosphine) palladium(0) In ethanol; water at 75℃; for 3h; Suzuki Coupling;	100%

2,4-difluorophenylboronic acid (144025-03-6) → 2-bromo-6-(2,4-difluorophenyl)pyridine (1380281-57-1)

Conditions	Yield
With sodium carbonate; tetrakis(triphenylphosphine) palladium(0) In ethanol; water at 75℃; for 2.5h; Product distribution / selectivity; Suzuki Coupling;	100%

3-fluoro-5-iodosalicylic acid + 2,4-difluorophenylboronic acid (144025-03-6) → 2′,4′,5-trifluoro-4-hydroxy-[1,1′-biphenyl]-3-carboxylic acid

Conditions	Yield
With palladium diacetate; sodium carbonate In water at 20℃; for 3h; Suzuki Coupling; Inert atmosphere;	100%

para-nitrophenyl bromide (586-78-7) + 2,4-difluorophenylboronic acid (144025-03-6) → 2,4-difluoro-4′-nitrobiphenyl (1178888-74-8)

Conditions	Yield
With 1,1',1'',1'''-benzene-1,2,4,5-tetrayltetrakis(methylene)tetrakis-(piperidin-4-ol); palladium diacetate; potassium carbonate In ethanol; water at 20℃; Suzuki-Miyaura Coupling;	100%

5-ethyl-4-iodo-2(5H)-furanone (1015792-46-7) + 2,4-difluorophenylboronic acid (144025-03-6) → 4-(2,4-difluorophenyl)-5-ethylfuran-2(5H)-one

Conditions	Yield
With 1,1',1'',1'''-benzene-1,2,4,5-tetrayltetrakis(methylene)tetrakis-(piperidin-4-ol); palladium diacetate; potassium carbonate In ethanol; water at 20℃; for 0.25h; Suzuki-Miyaura Coupling;	100%

4-(methylcyclohexyloxy)-2-chloropyridine + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenyl)-4-(methylcyclohexyloxy)pyridine

Conditions	Yield
With palladium diacetate; sodium carbonate; triphenylphosphine In 1,4-dioxane; water Suzuki-Miyaura Coupling; Inert atmosphere; Reflux;	100%

5-bromosalicyclic acid (89-55-4) + 2,4-difluorophenylboronic acid (144025-03-6) → 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid (22494-42-4)

Conditions	Yield
With 2-[5-(4-methylphenyl)isoxazol-3-yl]-5-(5-phenylisoxazol-3-yl)-1,3,4-oxadiazole·2PdCl2; potassium carbonate In water; N,N-dimethyl-formamide at 100℃; for 0.0166667h; Suzuki Coupling;	99%
With potassium carbonate; palladium dichloride In water; N,N-dimethyl-formamide at 75℃; Temperature; Solvent; Reagent/catalyst; Sonication; Cooling;	98.37%
With C11H8Cl4N2O3Pd; potassium carbonate In methanol; water; N,N-dimethyl-formamide at 100℃; for 0.0833333h; Suzuki Coupling;	97%

4-chloromethoxybenzene (623-12-1) + 2,4-difluorophenylboronic acid (144025-03-6) → 2,4-difluoro-4'-methoxybiphenyl (90101-30-7)

Conditions	Yield
With dicyclohexyl-(2',6'-dimethoxybiphenyl-2-yl)-phosphane; potassium phosphate; palladium diacetate In toluene at 80℃; for 16h; Suzuki-Miyaura coupling;	99%
With potassium carbonate; 2-(dicyclohexylphosphino)-2'-methylbiphenyl; palladium on activated charcoal In N,N-dimethyl acetamide; water at 100℃; for 2h; Suzuki-Miyaura cross-coupling;	64%

C29H29N3O4S (1144042-97-6) + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenylthio)-N-isopropylbenzamide (1144043-13-9) + (+)-(S)-2-(benzyloxycarbonylamino)-1-(2,4-difluorophenyl)-3-(1H-indol-3-yl)propan-1-one (1144042-90-9)

Conditions	Yield
With copper(I) 2-hydroxy-3-methylbenzoate; oxygen In N,N-dimethyl-formamide at 23℃; for 3h; optical yield given as %ee;	A 99% B 97%

4-bromo-5H-furan-2-one (56634-50-5) + 2,4-difluorophenylboronic acid (144025-03-6) → 4-(2,4-difluorophenyl)furan-2(5H)-one

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; potassium fluoride In tetrahydrofuran; water for 5h; Inert atmosphere; Reflux;	99%

C17H18BrNS2 (1201683-05-7) + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenyl)-4-(5-hexylthieno[3,2-b]thien-2-yl)pyridine (1341232-96-9)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In tetrahydrofuran; water at 70℃; for 0.333333h; Suzuki coupling; Inert atmosphere; Microwave irradiation;	99%

4-methoxyphenyl p-toluenesulfonate (3899-91-0) + 2,4-difluorophenylboronic acid (144025-03-6) → 2,4-difluoro-4'-methoxybiphenyl (90101-30-7)

Conditions	Yield
With potassium phosphate; nickelocene; tricyclohexylphosphine In tetrahydrofuran at 20℃; for 8h; Reagent/catalyst; Glovebox; Inert atmosphere;	99%

naphthalen-2-yl tosylate (7385-85-5) + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenyl)naphthalene

Conditions	Yield
With potassium phosphate; bis(tricyclohexylphosphine)nickel(II) bromide In tetrahydrofuran; water at 20℃; Reagent/catalyst; Glovebox;	99%

2,4-difluorophenylboronic acid (144025-03-6) + 3-methoxycarbonylphenyl tosylate → methyl 3-(2,4-difluorophenyl)benzoate

Conditions	Yield
With potassium phosphate; bis(tricyclohexylphosphine)nickel(II) bromide In tetrahydrofuran; water at 20℃; Glovebox;	99%

2,6-dichloro-4-iodopyridine (98027-84-0) + 2,4-difluorophenylboronic acid (144025-03-6) → 2,6-dichloro-4-(2,4-difluorophenyl)pyridine

Conditions	Yield
With (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; sodium hydrogencarbonate In 1,2-dimethoxyethane; water at 90℃; for 1h; Inert atmosphere;	98.5%

para-bromoacetophenone (99-90-1) + 2,4-difluorophenylboronic acid (144025-03-6) → 1-(2',4'difluoro[1,1']biphenyl-4-yl)ethanone (53591-79-0)

Conditions	Yield
With C20H12N2O8PdS2(2-)*2Na(1+); sodium hydroxide In water at 100℃; for 6h;	98%
With C40H56Cl2FeN2O4P2; sodium carbonate In water; acetone at 20℃; for 4h; Suzuki coupling;	92%
With [Pd(N-(3-chloro-2-quinoxalinyl)-N'-(2,6-diisopropylphenyl)imidazolium)(PPh3)Cl2]; potassium carbonate In water at 70℃; for 3h; Catalytic behavior; Suzuki-Miyaura Coupling;	55%
With cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclope; potassium carbonate; bis(η3-allyl-μ-chloropalladium(II)) In xylene at 130℃; for 20h; Suzuki cross-coupling reaction;
With (R,R)-N,N'-bis[(2,4-dimethoxyphenyl)methyl]-1,2-cyclohexanediamine PdCl2 complex; potassium carbonate In N,N-dimethyl-formamide at 120℃; for 24h; Reactivity; Reagent/catalyst; Suzuki coupling; Aerobic conditions;	99 %Spectr.

6-bromo-N-phenyl-N-(pyridin-2-yl)pyridin-2-amine (1246612-19-0) + 2,4-difluorophenylboronic acid (144025-03-6) → F2C6H3C5H3NN(C6H5)C5H4N (1246612-18-9)

Conditions	Yield
With palladium diacetate; potassium carbonate; triphenylphosphine In 1,2-dimethoxyethane; water for 6h; Inert atmosphere; Reflux;	98%

n-butyldiethanolamine (102-79-4) + 2,4-difluorophenylboronic acid (144025-03-6) → 6-butyl-2-(2',4'-difluorophenyl)-(N-B)-1,3,6,2-dioxazaborocane

Conditions	Yield
With magnesium sulfate In acetone at 35℃; for 1h;	98%

2-chloro-4-methylquinoline (634-47-9) + 2,4-difluorophenylboronic acid (144025-03-6) → 2-(2,4-difluorophenyl)-4-methylquinoline

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); sodium carbonate In ethanol; water; toluene at 110℃; for 16h; Suzuki-Miyaura Coupling; Inert atmosphere;	98%
Suzuki Coupling; Inert atmosphere; Schlenk technique;

C16H19NO4S + 2,4-difluorophenylboronic acid (144025-03-6) → C20H19F2NO2S

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; potassium phosphate In 1,4-dioxane at 50℃; for 8h; Inert atmosphere; regioselective reaction;	98%

2-bromo-9H-fluorene (1133-80-8) + 2,4-difluorophenylboronic acid (144025-03-6) → C19H12F2

Conditions	Yield
With C35H40N4O9(2+)*2Cl(1-); palladium diacetate; potassium hydroxide In ethanol at 100℃; for 1.5h; Suzuki Coupling; Green chemistry;	98%

2-hydroxy-5-iodobenzoic acid (119-30-2) + 2,4-difluorophenylboronic acid (144025-03-6) → 2',4'-difluoro-4-hydroxybiphenyl-3-carboxylic acid (22494-42-4)

Conditions	Yield
With C32H26Cl2N8O4Pd2; potassium carbonate In methanol; water for 0.0833333h; Suzuki-Miyaura Coupling; Reflux;	98%
With choline chloride; palladium diacetate; sodium carbonate; glycerol at 60℃; for 5h; Suzuki-Miyaura Coupling;	52%

7-{[(6-bromopyridin-2-yl)oxy]methyl}-7-methyl-2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine + 2,4-difluorophenylboronic acid (144025-03-6) → 7-({[6-(2,4-difluorophenyl)pyridin-2-yl]oxy}methyl)-7-methyl-2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine

Conditions	Yield
With (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; sodium carbonate In ethanol; water; N,N-dimethyl-formamide; toluene at 86℃; for 2.66667h; Suzuki Coupling; Inert atmosphere;	97%

2-bromo-5-chlorobenzaldehyde (174265-12-4) + 2,4-difluorophenylboronic acid (144025-03-6) → 4-chloro-2',4'-difluoro-[1,1'-biphenyl]-2-carbaldehyde

Conditions	Yield
With potassium phosphate monohydrate; C66H84O10P2Pd In water; toluene at 45℃; for 3h; Reagent/catalyst; Solvent; Suzuki-Miyaura Coupling; Inert atmosphere;	97%
With potassium phosphate monohydrate; C50H64NO6PPdS In water at 45℃; for 3h; Suzuki-Miyaura Coupling; Inert atmosphere; Sealed tube;

m-bromobenzoic acid (585-76-2) + 2,4-difluorophenylboronic acid (144025-03-6) → 2',4'-difluoro-[1,1'-biphenyl]-3-carboxylic acid

Conditions	Yield
With 4-(di-tert-butylphosphino)ethyltrimethylammonium chloride; sodium carbonate; sodium tetrachloropalladate(II) In water at 20℃; Suzuki reaction;	96%

4-chloro-aniline (106-47-8) + 2,4-difluorophenylboronic acid (144025-03-6) → 2',4'-difluoro[1,1'-biphenyl]-4-amine

Conditions	Yield
With dicyclohexyl-(2',6'-dimethoxybiphenyl-2-yl)-phosphane; potassium phosphate; palladium diacetate In toluene at 80℃; for 10h; Suzuki-Miyaura coupling;	96%

Upstream product

• 121-43-7 Trimethyl borate 
• 144025-04-7 (2,4-difluorophenyl)magnesium bromide 
• 348-57-2 2,4-difluorobromobenzene 
• 688-71-1 tri-n-propyl borate 
• 7732-18-5 water 
• 109-86-4 2-methoxy-ethanol 
• 512198-16-2 tris(2,4-difluorophenyl)boroxine 
• 871300-65-1 C₆H₃BF₅^(1-) 

Downstream Products

• 59089-67-7 4-(2,4-difluorophenyl)phenyl acetate 
• 872973-93-8 7-chloro-1-(2,6-dichlorophenyl)-5-(2,4-difluorophenyl)-1,6-naphthyridin-2-(1H)-one 
• 872342-09-1 [1-(2',4'-difluoro-biphenyl-4-ylmethyl)-2-oxo-2-thiazolidin-3-yl-ethyl]-carbamic acid tert-butyl ester 
• 872342-02-4 [(S)-2-((S)-2-Cyano-pyrrolidin-1-yl)-1-(2',4'-difluoro-biphenyl-4-ylmethyl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 
• 959600-53-4 N-[5-(2,4-difluoro-phenyl)-3-(2-methoxyethyl)-1,3-thiazol-2(3H)-ylidene]acetamide 
• 852121-74-5 (+/-)-{[7-(2,4-difluorophenyl)-5-fluoro-2,3-dihydro-1-benzofuran-2-yl]methyl}amine 
• 852122-86-2 (+/-)-{[7-(2,4-difluorophenyl)-5-(trifluoromethyl)-2,3-dihydro-1-benzofuran-2-yl]methyl}amine 
• 852123-13-8 (+/-)-{[7-(2,4-difluorophenyl)-5-phenyl-2,3-dihydro-1-benzofuran-2-yl]methyl}amine 

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