14559-88-7

Basic information

• Product Name: 2,2-DIMETHYLETHENYLBORONIC ACID
• Synonyms: 2,2-DIMETHYLETHENYLBORONIC ACID;RARECHEM AH PB 0256;2,2-DIMETHYLETHENYLBORONIC ACID 97%;B-(2-methyl-1-propen-1-yl)boronic acid;Boronic acid,B-(2-methyl-1-propen-1-yl)-;(2-Methylprop-1-en-1-yl)boronic acid
• CAS NO: 14559-88-7
• Molecular Formula: C₄H₉BO₂
• Molecular Weight: 99.92
• Product Categories: Boronic acids
• Mol File: 14559-88-7.mol
• Article Data: 9

Chemical Properties

• Melting Point: 87 °C
• Boiling Point: 190.6 °C at 760 mmHg
• Flash Point: 69.1 °C
• Appearance: /
• Density: 0.952 g/cm³
• Vapor Pressure: 0.145mmHg at 25°C
• Refractive Index: 1.427
• Storage Temp.: Inert atmosphere,Store in freezer, under -20°C
• PKA: 9.82±0.43(Predicted)
• CAS DataBase Reference: 2,2-DIMETHYLETHENYLBORONIC ACID(CAS DataBase Reference)
• NIST Chemistry Reference: 2,2-DIMETHYLETHENYLBORONIC ACID(14559-88-7)
• EPA Substance Registry System: 2,2-DIMETHYLETHENYLBORONIC ACID(14559-88-7)

Safety Data

• Hazardous Substances Data: 14559-88-7(Hazardous Substances Data)

Usage

Uses

2,2-Dimethylethenylboronic acid is a useful reagent in the preparation of prostaglandins via 1,4-conjugate addition.

InChI:InChI=1/C4H9BO2/c1-4(2)3-5(6)7/h3,6-7H,1-2H3

Synthetic route

Triisopropyl borate (5419-55-6) + 2-methyl-1-propenylbromide (3017-69-4) + water (7732-18-5) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
Stage #1: Triisopropyl borate; 2-methyl-1-propenylbromide With lithium In tetrahydrofuran at -50 - -40℃; Inert atmosphere; Stage #2: water With hydrogenchloride In tetrahydrofuran at 0 - 10℃; pH=3 - 4; Temperature; Reagent/catalyst; Inert atmosphere;	60.3%

2-methylpropen-1-ylmagnesium bromide (38614-36-7) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
With Trimethyl borate; lithium chloride In tetrahydrofuran; diethyl ether at -78 - 20℃; Inert atmosphere;	55%
With Trimethyl borate In diethyl ether at -78 - 20℃;	41%
Stage #1: 2-methylpropen-1-ylmagnesium bromide With Trimethyl borate In tetrahydrofuran at -78 - 20℃; Inert atmosphere; Stage #2: With hydrogenchloride; water In tetrahydrofuran at 0 - 20℃; for 1.5h; Inert atmosphere;
Stage #1: 2-methylpropen-1-ylmagnesium bromide With Trimethyl borate In tetrahydrofuran at -70 - 20℃; for 3.58333h; Inert atmosphere; Stage #2: With N-methyliminodiacetic acid In tetrahydrofuran; dimethyl sulfoxide at 120 - 150℃; for 1h; Inert atmosphere; Stage #3: With water; sodium hydroxide In tetrahydrofuran at 20℃; for 0.25h;

2-methyl-1-propenylbromide (3017-69-4) + chloro-bis(dimethylamino)borane (6562-41-0) + water (7732-18-5) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
Stage #1: 2-methyl-1-propenylbromide; chloro-bis(dimethylamino)borane With lithium In tetrahydrofuran at -78 - -70℃; Inert atmosphere; Stage #2: water With hydrogenchloride In tetrahydrofuran at 0 - 10℃; pH=3 - 4; Inert atmosphere;	46.9%

Trimethyl borate (121-43-7) + 2-methylprop-1-enyllithium (29917-94-0) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
und anschliessend mit wss.HCl;

Trimethyl borate (121-43-7) + 2-methylpropen-1-ylmagnesium bromide (38614-36-7) → 2,2-dimethylethenylboronic acid (14559-88-7)

tris(ethylenedioxyboryl)methane (59278-44-3) + acetone (67-64-1) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
(i) MeLi, Et2O, THF, CH2Cl2, (ii) /BRN= 635680/; Multistep reaction;

Trimethyl borate (121-43-7) + 2-methyl-propenyl magnesium halide → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
und Erwaermen des Reaktionsprodukts mit wss.H2SO4;

C10H21BO2 → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
With water; ammonium chloride In pentane at 20℃; for 0.5h;

C6H13BO2 (90011-02-2) → 2,2-dimethylethenylboronic acid (14559-88-7)

Conditions	Yield
With hydrogenchloride; water In tetrahydrofuran at 0 - 20℃; for 1.5h;

2,2-dimethylethenylboronic acid (14559-88-7) + methyl 3-bromo-4-(tetrahydro-2H-pyran-2-yloxy)benzoate (1142224-41-6) → methyl 3-(2-methyl-1-propenyl)-4-(tetrahydro-2H-pyran-2-yloxy)benzoate (1142225-87-3)

Conditions	Yield
With dicyclohexyl-(2',6'-dimethoxybiphenyl-2-yl)-phosphane; potassium phosphate; palladium diacetate In water; N,N-dimethyl-formamide at 70℃; for 23h; Inert atmosphere;	100%
With potassium phosphate; 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl; palladium diacetate In water; N,N-dimethyl-formamide at 70℃; for 23h; Suzuki Coupling; Inert atmosphere;	100%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-(pyrazin-2-yl)but-3-en-2-one (1414846-58-4) → 6-methyl-4-(pyrazin-2-yl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 70℃; for 8h; Molecular sieve; Inert atmosphere; enantioselective reaction;	99%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-(2,4,6-trimethoxyphenyl)but-3-en-2-one (42811-79-0) → 6-methyl-4-(2,4,6-trimethoxyphenyl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 115℃; for 1h; Molecular sieve; Inert atmosphere; enantioselective reaction;	99%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-(2-thienyl)but-3-en-2-one (874-83-9, 33603-63-3) → 6-methyl-4-(thiophen-2-yl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 115℃; for 2h; Molecular sieve; Inert atmosphere; enantioselective reaction;	99%

2,2-dimethylethenylboronic acid (14559-88-7) + (Z)-7-[(3R)-3-(tert-butyldimethylsilanyloxy)-5-oxo-cyclopent-1-enyl]hept-5-enoic acid isopropyl ester (474944-36-0) → (Z)-7-[(2R,3R)-3-(tert-butyl-dimethylsilanyloxy)-2-(2-methyl-prop-1-enyl)-5-oxo-cyclopentyl]hept-5-enoic acid isopropyl ester

Conditions	Yield
With chloro(1,5-cyclooctadiene)rhodium(I) dimer; potassium hydroxide In methanol; water at 3℃; for 72h; Temperature; Inert atmosphere; diastereoselective reaction;	99%

2,2-dimethylethenylboronic acid (14559-88-7) + N-(5-chloro[1,2,4]triazolo[1,5-a]pyridin-2-yl)nicotinamide (1124382-78-0) → N-[5-(2-methylprop-1-en-1-yl)[1,2,4]triazolo[1,5-a]pyridin-2-yl]nicotinamide dihydrochloride

Conditions	Yield
Stage #1: 2,2-dimethylethenylboronic acid; N-(5-chloro[1,2,4]triazolo[1,5-a]pyridin-2-yl)nicotinamide With cesium fluoride; bis-triphenylphosphine-palladium(II) chloride In tetrahydrofuran; water at 120℃; Suzuki-Miyaura reaction; Stage #2: With hydrogenchloride In diethyl ether; dichloromethane	96%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-(quinolin-2-yl)but-3-en-2-one (137479-63-1) → 6-methyl-4-(quinolin-2-yl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 70℃; for 5h; Molecular sieve; Inert atmosphere; enantioselective reaction;	96%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-(1-methyl-1H-imidazol-2-yl)but-3-en-2-one (1414846-63-1) → 6-methyl-4-(1-methyl-1H-imidazol-2-yl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 115℃; for 12h; Molecular sieve; Inert atmosphere; enantioselective reaction;	94%

2,2-dimethylethenylboronic acid (14559-88-7) + 2-(3-bromo-2-methylbenzoylamino)indan-2-carboxylic acid ethyl ester (1092449-74-5) → 2-[2-methyl-3-(2-methyl-1-propenyl)benzoylamino]indan-2-carboxylic acid ethyl ester (1092449-75-6)

Conditions	Yield
With sodium hydrogencarbonate; tetrakis(triphenylphosphine) palladium(0) In water; N,N-dimethyl-formamide at 110℃; for 5h;	92%

2,2-dimethylethenylboronic acid (14559-88-7) + 4-(pyridin-4-yl)-3-buten-2-one (94445-75-7) → 6-methyl-4-(pyridin-4-yl)hept-5-en-2-one

Conditions	Yield
With (R)-3,3’-bis(2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl)-1,1’-binaphthyl-2,2’-diol; magnesium 2-methylpropan-2-olate In toluene at 115℃; for 22h; Molecular sieve; Inert atmosphere; enantioselective reaction;	91%

2,2-dimethylethenylboronic acid (14559-88-7) + (S)-(5-(hydroxymethyl)-1-tosyl-7-(((trifluoromethyl)sulfonyl)oxy)-1,2,3,5-tetrahydrocyclopenta[f]indol-5-yl)methyl benzoate → (S)-(5-(hydroxymethyl)-7-(2-methylprop-1-en-1-yl)-1-tosyl-1,2,3,5-tetrahydrocyclopenta[f]indol-5-yl)methyl benzoate

Conditions	Yield
With dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH2Cl2; caesium carbonate In water; toluene at 50℃; for 6h; Inert atmosphere; Darkness;	90%

2,2-dimethylethenylboronic acid (14559-88-7) + 1,1-dimethylethyl 9-bromo-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (1055880-27-7) → tert-butyl 9-(2-methylpropa-1-ene-1-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (1055880-88-0)

Conditions	Yield
With sodium carbonate; tetrakis(triphenylphosphine) palladium(0) In 1,2-dimethoxyethane; water at 85℃; for 12h; Inert atmosphere; Saturated solution;	89.1%

2,2-dimethylethenylboronic acid (14559-88-7) + (E)-4-pyridin-3-ylbut-3-en-2-one (28447-16-7, 94445-77-9) → 6-methyl-4-(pyridin-3-yl)hept-5-en-2-one

Conditions	Yield
With (1R,3'r)-3,3'-bis(perfluorophenyl)[1,1'-binaphthalene]-2,2'-diol; magnesium 2-methylpropan-2-olate In toluene at 115℃; for 15h; Molecular sieve; Inert atmosphere; enantioselective reaction;	88%

2,2-dimethylethenylboronic acid (14559-88-7) + benzo[e][1,2,3]oxathiazine 2,2-dioxide (71730-46-6) → (R)-4-(2-methylprop-1-en-1-yl)-3,4-dihydrobenzo[e][1,2,3]oxathiazine 2,2-dioxide

Conditions	Yield
With nickel(II) perchlorate hexahydrate; C30H28NOP In 2,2,2-trifluoroethanol at 70℃; for 48h;	87%
With (1R,1’R,2S,2’S)-2,2’-di-tert-butyl-2,3,2’,3’-tetrahydro-1H,1‘H-(1,1‘)biisophosphindolyl; potassium carbonate; cobalt(II) bromide In tetrahydrofuran at 70℃; for 24h; Inert atmosphere; enantioselective reaction;	70%

1-Benzenesulfonyl-5-bromo-3-[2-(1-methyl-piperidin-4-yl)-thiazol-4-yl]-1H pyrrolo[2,3-b]pyridine (1046793-45-6) + 2,2-dimethylethenylboronic acid (14559-88-7) → 1-Benzenesulfonyl-3-[2-(1-methyl-piperidin-4-yl)-thiazol-4-yl]-5-(2-methyl-propenyl)-1H-pyrrolo[2,3-b]pyridine

Conditions	Yield
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene Suzuki-Miaura reaction; Heating / reflux;	86%
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene at 110℃; for 1.5h; Suzuki Coupling;	86%

4-(1-Benzenesulfonyl-5-bromo-1H-pyrrolo[2,3-b]pyridin-3-yl)-thiazole-2-carboxylic acid ethyl ester (1046793-41-2) + 2,2-dimethylethenylboronic acid (14559-88-7) → 4-[1-Benzenesulfonyl-5-(2-methyl-propenyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]-thiazole-2-carboxylic acid ethyl ester

Conditions	Yield
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene at 110℃; for 1.5h; Suzuki-Miaura reaction; Heating / reflux;	85%
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene at 110℃; for 1.5h; Suzuki Coupling;	85%

2,2-dimethylethenylboronic acid (14559-88-7) + indole-2,3-dione (91-56-5) → (S)-3-hydroxy-3-(2-methylprop-1-en-1-yl)indolin-2-one

Conditions	Yield
With (1R,1’R,2S,2’S)-2,2’-di-tert-butyl-2,3,2’,3’-tetrahydro-1H,1‘H-(1,1‘)biisophosphindolyl; potassium carbonate; cobalt(II) bromide In tetrahydrofuran at 70℃; for 40h; Inert atmosphere; enantioselective reaction;	80%

2,2-dimethylethenylboronic acid (14559-88-7) + N-methyl-2-iodoaniline (57056-93-6) → N-methyl-N-[2-(2-methylpropenyl)phenyl]amine (41652-76-0)

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); potassium carbonate In ethanol; water; toluene at 80℃; for 12h;	80%

2,2-dimethylethenylboronic acid (14559-88-7) + tert-butyl 2-[3-acetyl-5-bromo-7-(prop-2-en-1-yl)indazol-1-yl]acetate → tert-butyl 2-(3-acetyl-7-allyl-5-(2-methylprop-1-en-1-yl)-1H-indazol-1-yl)acetate

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); potassium carbonate In 1,4-dioxane; water at 90℃; for 16h; Inert atmosphere;	79.9%

2,2-dimethylethenylboronic acid (14559-88-7) + (3S,8aR)-5-oxo-1,2,3,5,8,8a-hexahydroindolizine-3-carboxylic acid methyl ester → (3S,8aR)-6-(2-methylprop-1-en-1-yl)-5-oxo-1,2,3,5,8,8a-hexahydroindolizine-3-carboxy methyl ester

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); caesium carbonate In 1,4-dioxane; water at 100℃; for 12h; Sealed tube; Inert atmosphere;	78.1%

2,2-dimethylethenylboronic acid (14559-88-7) + 2-(2-iodo-3-methyl-benzoylamino)-indane-2-carboxylic acid ethyl ester (1092447-82-9) → 2-[3-methyl-2-(2-methyl-propenyl)-benzoylamino]-indan-2-carboxylic acid ethyl ester (1092447-84-1)

Conditions	Yield
With caesium carbonate; (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride In 1,4-dioxane; water at 110℃; for 2h; Microwave irradiation;	78%

2,2-dimethylethenylboronic acid (14559-88-7) + anthranilic acid amide (28144-70-9) → 2-(2-methylprop-1-en-1-yl)-2,3-dihydrobenzo[d][1,3,2]diazaborinin-4(1H)-one

Conditions	Yield
With dibromobis(triphenylphosphine)nickel(II); triethylamine; palladium dichloride In ethanol at 20℃; for 2h; Green chemistry; chemoselective reaction;	75%

2,2-dimethylethenylboronic acid (14559-88-7) + methyl (3S,9aS)-6-bromo-5-oxo-2,3,5,8,9,9a-hexahydro-1H-pyrrolo[1,2-a]azepine-3-carboxylate → (3S,9aS)-6-(2-methylprop-1-en-1-yl)-5-oxo-2,3,5,8,9,9a-hexahydro-1H-pyrrolo[1,2-a]azepine-3-carboxylic acid methyl ster

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); caesium carbonate In 1,4-dioxane; water at 100℃; for 12h; Sealed tube; Inert atmosphere;	74.6%

2,2-dimethylethenylboronic acid (14559-88-7) → tris(2-methylpropene-1-yl) boroxine (1010113-27-5)

Conditions	Yield
With magnesium sulfite In pyridine; diethyl ether at 20℃;	73%
byproducts: H2O; dehydration;;
byproducts: H2O; dehydration;;

2,2-dimethylethenylboronic acid (14559-88-7) + 5-fluoro-2-(2-iodo-3-methyl-benzoylamino)indan-2-carboxylic acid ethyl ester (1092446-64-4) → 5-fluoro-2-[3-methyl-2-(2-methyl-propenyl)-benzoylamino]-indan-2-carboxylic acid ethyl ester (1092447-88-5)

Conditions	Yield
With potassium carbonate; palladium anchored homogeneous catalyst, FibreCatPd(0) (4.84percentPd) In 1,4-dioxane; ethanol; water at 120℃; for 7h; Microwave irradiation;	73%

2,2-dimethylethenylboronic acid (14559-88-7) + 5,5-bis(hydroxymethyl)-1-tosyl-1,2,3,5-tetrahydrocyclopenta[f]indol-7-yl trifluormethansulfonate → (7-(2-methylprop-1-en-1-yl)-1-tosyl-1,2,3,5-tetrahydrocyclopenta[f]indole-5,5-diyl)dimethanol

Conditions	Yield
With dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH2Cl2; caesium carbonate In water; toluene at 50℃; for 6h; Suzuki-Miyaura Coupling; Sonication; Darkness;	71%

2,2-dimethylethenylboronic acid (14559-88-7) + 3-methyl-3-phenylcyclopropene (65051-83-4) → ((1S,2R)-1-methyl-2-(2-methylprop-1-en-1-yl)cyclopropyl)benzene

Conditions	Yield
With potassium carbonate; cobalt(II) chloride; [2R-[1(2'R*,5'R*),2a,5b]]-1,1'-(1,2-phenylene)bis[2,5-dimethylphospholane] In tetrahydrofuran at 70℃; for 12h; Inert atmosphere; Sealed tube; stereoselective reaction;	70%

2,2-dimethylethenylboronic acid (14559-88-7) + C10H11BrN2O2 → C14H18N2O2

Conditions	Yield
With palladium diacetate; cesium fluoride; tris-(o-tolyl)phosphine In 1,4-dioxane at 75℃; for 20h; Temperature; Solvent; Inert atmosphere;	68.2%

2,2-dimethylethenylboronic acid (14559-88-7) + 1-(4-bromo-2-chloro-phenyl)-1-cyclopropyl-2-(1,2,4-triazol-1-yl)ethanol (1615663-83-6) → 1-(2-chloro-4-(2-methylprop-1-en-1-yl)phenyl)-1-cyclopropyl-2-(1H-1,2,4-triazol-1-yl)ethan-1-ol

Conditions	Yield
With (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; tetrakis(triphenylphosphine) palladium(0); sodium carbonate In 1,2-dimethoxyethane; water at 90℃; for 14h;	67%

4-(2-(4-(5-bromo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridin-3-yl)-1H-pyrazol-1-yl)ethyl)morpholine (923584-14-9) + 2,2-dimethylethenylboronic acid (14559-88-7) → 1-Benzenesulfonyl-5-(2-methyl-propenyl)-3-[1-(2-morpholin-4-yl-ethyl)-1H-pyrazol-4-yl]-1H-pyrrolo[2,3-b]pyridine (923584-06-9)

Conditions	Yield
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene for 3h; Suzuki-Miaura reaction; Heating / reflux;	66%
With sodium carbonate; lithium chloride; bis-triphenylphosphine-palladium(II) chloride In ethanol; water; toluene at 115℃; for 3h; Suzuki Coupling;	66%

Upstream product

• 5419-55-6 Triisopropyl borate 
• 3017-69-4 2-methyl-1-propenylbromide 
• 7732-18-5 water 
• 6562-41-0 chloro-bis(dimethylamino)borane 
• 59278-44-3 tris(ethylenedioxyboryl)methane 
• 67-64-1 acetone 
• 121-43-7 Trimethyl borate 
• 38614-36-7 2-methylpropen-1-ylmagnesium bromide 
• 29917-94-0 2-methylprop-1-enyllithium 
• 90011-02-2 C₆H₁₃BO₂ 

Downstream Products

• 1380240-10-7 mesityl(2-methylprop-1-en-1-yl)iodonium trifluoromethanesulfonate 
• 86123-18-4 Benzoesaeure-(2-methyl-1-propenylester) 
• 41652-76-0 N-methyl-N-[2-(2-methylpropenyl)phenyl]amine 
• 1336967-04-4 methyl 3-(1,4'-bipiperidin-1'-ylmethyl)-7-(2-methyl-1-propen-1-yl)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxylate 

Relevant articles and documents

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Preparation of 2,2-dimethyl-vinyl boric acid method

The invention belongs to the technical field of chemical industry, and in particular discloses a method for preparing 2,2-dimethyl vinyl boric acid. The method is characterized by comprising the steps of enabling an organic solvent 1 and 3,3-dimethyl acrylic acid to react with bromine for 3-4 hours at 10-60 DEG C, adjusting the pH value to 9-10 by using alkali after reaction, reacting for 2-3 hours at 30-60 DEG C, standing for layering after reaction, and distilling an organic layer to obtain 2,2-dimethyl vinyl bromine; enabling an organic solvent 2 to react with 2,2-dimethyl vinyl bromine for 2-3 hours at minus 78 to minus 40 DEG C under the action of lithium and a boronizing agent, adjusting the pH value to 3-4 by using hydrochloric acid, performing extraction by using acetic ether, concentrating an organic layer, pulping and filtering through a non-polar hydrocarbon solvent, and drying to obtain 2,2-dimethyl vinyl boric acid. The method disclosed by the invention has the characteristics of safety, environment friendliness and easiness in operation, and is suitable for industrial production.

Enantioselective conjugate addition of alkenylboronic acids to indole-appended enones

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