40307-11-7

Basic information

• Product Name: 4-Ethylphenylacetylene
• Synonyms: 4-ETHYLPHENYLACETYLENE;1-ETHYL-4-ETH-1-YNYLBENZENE;1-ETHYL-4-ETHYNYL-BENZENE;BENZENE, 1-ETHYL-4-ETHYNYL-;Benzene, 1-ethyl-4-ethynyl- (6CI, 9CI);4-Ethylphenylacetylene 97%;4-Ethylphenylacetylene97%;1-ETH-1-YNYL-4-ETHYLBENZENE
• CAS NO: 40307-11-7
• Molecular Formula: C₁₀H₁₀
• Molecular Weight: 130.19
• Product Categories: Aromatic Compounds;Acetylenes;Acetylenic Hydrocarbons having Benzene Ring;Alkynes;Organic Building Blocks;Terminal;Liquid crystal intermediates
• Mol File: 40307-11-7.mol
• Article Data: 7

Chemical Properties

• Boiling Point: 30 °C0.05 mm Hg(lit.)
• Flash Point: 160 °F
• Appearance: /
• Density: 0.930 g/mL at 25 °C(lit.)
• Vapor Pressure: 1.04mmHg at 25°C
• Refractive Index: n20/D 1.5420(lit.)
• Storage Temp.: Keep in dark place,Sealed in dry,Room Temperature
• CAS DataBase Reference: 4-Ethylphenylacetylene(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Ethylphenylacetylene(40307-11-7)
• EPA Substance Registry System: 4-Ethylphenylacetylene(40307-11-7)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 16-26-36-37/39
• RIDADR: UN 3334
• WGK Germany: 3
• Hazardous Substances Data: 40307-11-7(Hazardous Substances Data)

Usage

Chemical Properties

Yellow liquid

Uses

Different sources of media describe the Uses of 40307-11-7 differently. You can refer to the following data:
1. Intermediates of Liquid Crystals
2. 1-Ethyl-4-ethynylbenzene may be used to synthesize:2,4-bis[(4-ethylphenyl)ethynyl]-6-methoxy-1,3,5-triazine 2-[(4-ethylphenyl)ethynyl]-4-methoxy-6-(phenylethynyl)-1,3,5-triazine 2-chloro-4-[(4-ethylphenyl)ethynyl]-6-methoxy-1,3,5-triazine 4-chloro-6-[(4-ethylphenyl)ethynyl]-N,N-diphenyl-1,3,5-triazin-2-amine

General Description

1-Ethyl-4-ethynylbenzene undergoes homocoupling reaction in the presence of copper(I) chloride (catalyst) and air (oxidant) to yield symmetrical 1,4-disubstituted 1,3-diyne.

InChI:InChI=1/C10H10/c1-3-9-5-7-10(4-2)8-6-9/h1,5-8H,4H2,2H3

Synthetic route

(2-(4-ethylphenyl)ethynyl)trimethylsilane → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
With potassium trimethylsilonate In dimethyl sulfoxide at 70℃; for 6h; Sealed tube; Schlenk technique;	90%
With potassium carbonate In methanol at 20℃; for 7h;	79%
With potassium carbonate In methanol at 20℃; Inert atmosphere;
With potassium carbonate In methanol; water at 20℃;

4-ethylacetophenone (937-30-4) → 1-ethyl-4-ethynylbenzene (40307-11-7)

4-Ethyl-β,β'-dibromostyrene (59931-57-6) → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
With n-butyllithium In tetrahydrofuran 1.) -78 deg C, 1 h, 2.) r.t., 1 h;
With n-butyllithium In tetrahydrofuran; hexane; water

3-<4-ethyl-phenyl>-acrylic acid ethyl ester → 1-ethyl-4-ethynylbenzene (40307-11-7)

4-ethyl-1-<α.β-dichloro-vinyl>-benzene → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
With diethyl ether; sodium

4-ethylbenzylaldehyde (4748-78-1) → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1.) Ph3P, Zn / 1.) CH2Cl2, r.t., 48 h, 2.) 2 h 2: n-BuLi / tetrahydrofuran / 1.) -78 deg C, 1 h, 2.) r.t., 1 h View Scheme
Multi-step reaction with 2 steps 1: tetrachloromethane; dichloromethane; Petroleum ether 2: n-butyllithium / tetrahydrofuran; hexane; water View Scheme

dichlorotriphenylphosphine palladium + 4-ethyl-1-iodobenzene (25309-64-2) + copper(I) iodide (7681-65-4) + trimethylsilylacetylene (1066-54-2) → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
With potassium carbonate; triethylamine In methanol

4-ethyl-1-iodobenzene (25309-64-2) → 1-ethyl-4-ethynylbenzene (40307-11-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: tetrakis(triphenylphosphine) palladium(0); triethylamine; copper(I) bromide / toluene / 4 h / 20 °C / Inert atmosphere; Schlenk technique 2: potassium carbonate / methanol / 7 h / 20 °C View Scheme
Multi-step reaction with 2 steps 1: tetrakis(triphenylphosphine) palladium(0); copper(l) iodide; triethylamine / toluene / 5 h / 20 °C / Inert atmosphere 2: potassium carbonate / methanol / 20 °C / Inert atmosphere View Scheme
Multi-step reaction with 2 steps 1: bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine / tetrahydrofuran / 20 °C 2: potassium carbonate / methanol; water / 20 °C View Scheme

1-ethyl-4-ethynylbenzene (40307-11-7) + m-tolyl aldehyde (620-23-5) → 1-(4′-methylphenyl)isoquinoline (101273-46-5)

Conditions	Yield
With palladium diacetate; sodium carbonate; triphenylphosphine In toluene at 80℃; for 2h; Inert atmosphere;	100%

1-ethyl-4-ethynylbenzene (40307-11-7) + m-tolyl aldehyde (620-23-5) → 3-(4-ethylphenyl)-1-(m-tolyl)prop-2-yn-1-ol

Conditions	Yield
Stage #1: 1-ethyl-4-ethynylbenzene With n-butyllithium In tetrahydrofuran at -78℃; for 0.5h; Inert atmosphere; Stage #2: m-tolyl aldehyde In tetrahydrofuran at -78℃; for 3h; Inert atmosphere;	100%

1-ethyl-4-ethynylbenzene (40307-11-7) + 4-amino-3-iodobenzoic acid methyl ester (19718-49-1) → methyl 4-amino-3-((4-ethylphenyl)ethynyl)benzoate

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In toluene at 20℃;	100%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine at 20℃; Inert atmosphere;

1-ethyl-4-ethynylbenzene (40307-11-7) → 1,4-bis(p-ethylphenyl)buta-1,3-diyne (35672-48-1)

Conditions	Yield
With copper(l) iodide; ethyl bromoacetate; N-ethyl-N,N-diisopropylamine; bis-triphenylphosphine-palladium(II) chloride In tetrahydrofuran at 20℃;	99%
With N,N,N,N,-tetramethylethylenediamine; oxygen; 1,8-diazabicyclo[5.4.0]undec-7-ene; copper(l) chloride In acetonitrile at 24℃; for 24h;	99%
With pyridine; oxygen In ethanol at 80℃; for 8h; Glaser Coupling;	99%

1-ethyl-4-ethynylbenzene (40307-11-7) + benzyl bromide (100-39-0) → 1-benzyl-4-(4-ethyl-phenyl)-1H-1,2,3-triazole (1314406-59-1)

Conditions	Yield
With sodium azide; sodium 2-(1,2-dihydroxyethyl)-4-hydroxy-5-oxo-2,5-dihydro-furan-3-olate In ethanol at 80℃; for 8h;	99%
With sodium azide In ethanol at 80℃; for 8h;	99%
With copper(l) iodide; sodium azide; diethylamine In glycerol at 20℃; for 5.5h; Schlenk technique; Inert atmosphere; Green chemistry;	99%

4-iodobenzoic acid ethyl ester (51934-41-9) + 1-ethyl-4-ethynylbenzene (40307-11-7) → ethyl 4-((4-ethylphenyl)ethynyl)benzoate (1425541-80-5)

Conditions	Yield
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine at 0℃; Sonogashira Cross-Coupling; Inert atmosphere;	99%
With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine at 0℃; Kinetics; Sonogashira Cross-Coupling; Inert atmosphere;

4-toluenesulfonyl azide (941-55-9) + 1-ethyl-4-ethynylbenzene (40307-11-7) + methyl 3-(2-hydroxyphenyl)propiolate (425686-45-9) → C27H25NO5S (1241956-44-4)

Conditions	Yield
With copper(l) iodide; triethylamine In dichloromethane at 20℃; for 24h; Inert atmosphere;	98%

1-ethyl-4-ethynylbenzene (40307-11-7) + benzyl-methyl-amine (103-67-3) + Benzoylformic acid (611-73-4) → N-benzyl-3-(4-ethylphenyl)-N-methyl-1-phenylprop-2-yn-1-amine (1329710-08-8)

Conditions	Yield
With Fe3O4(at)CuSiO3 In neat (no solvent) at 100℃; for 16h; Inert atmosphere;	98%
With copper(I) bromide In toluene at 100℃; for 0.416667h; Microwave irradiation; Sealed vessel;	94%

trimethylsilyl cyanide (7677-24-9) + 1-ethyl-4-ethynylbenzene (40307-11-7) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → C28H32N4

Conditions

Yield

Stage #1: 1-ethyl-4-ethynylbenzene With n-butyllithium In tetrahydrofuran; hexane at -40℃; for 1h; Inert atmosphere; Schlenk technique; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; hexane at -40 - 20℃; for 1h; Inert atmosphere; Schlenk technique; Stage #3: trimethylsilyl cyanide In tetrahydrofuran; hexane at -78 - 20℃; for 4.5h; Inert atmosphere; Schlenk technique; regioselective reaction;

98%

(3-azidopropyl)benzene (27126-20-1) + 1-ethyl-4-ethynylbenzene (40307-11-7) + trifluoroacetic anhydride (407-25-0) → 6-(4-ethylphenyl)-4-(3-phenylpropyl)-3-(trifluoromethyl)-1,2,4-triazin-5(4H)-one

Conditions	Yield
With copper(l) iodide; triethylamine In tetrahydrofuran at 20℃; for 14h; Glovebox; Inert atmosphere; Sealed tube;	98%

1-ethyl-4-ethynylbenzene (40307-11-7) + N-Benzyl-2-iodo-N-(2-methyl-allyl)-benzamide → (R)-2-benzyl-4-(3-(4-ethylphenyl)prop-2-yn-1-yl)-4-methyl-3,4-dihydroisoquinolin-1(2H)-one

Conditions	Yield
With (R)-N-((R)-(3,5-di-tert-butylphenyl)(2-(diphenylphosphanyl)phenyl)methyl)-2-methylpropane-2-sulfinamide; palladium diacetate; caesium carbonate In dichloromethane; pentane at 60℃; for 48h; Inert atmosphere; Sealed tube; enantioselective reaction;	98%

1-ethyl-4-ethynylbenzene (40307-11-7) + benzyl chloride (100-44-7) → 1-benzyl-4-(4-ethyl-phenyl)-1H-1,2,3-triazole (1314406-59-1)

Conditions	Yield
With sodium azide; Cu2O#Al2O3 In water at 20℃; for 0.333333h;	97%
With sodium azide In water at 20℃; for 0.166667h;	96%
With sodium azide In water at 20℃; for 72h;	95%

1-ethyl-4-ethynylbenzene (40307-11-7) + benzaldehyde (100-52-7) → (E)-1-(4-ethylphenyl)-3-phenylprop-2-en-1-one (26708-48-5)

Conditions	Yield
With amberlyst-15 resin at 90℃; Microwave irradiation; Neat (no solvent);	97%

1-ethyl-4-ethynylbenzene (40307-11-7) + benzyl azide (622-79-7) → 1-benzyl-4-(4-ethyl-phenyl)-1H-1,2,3-triazole (1314406-59-1)

Conditions	Yield
With copper(l) iodide; ammonia; ascorbic acid at 20℃; for 10h;	97%
Stage #1: 1-ethyl-4-ethynylbenzene; benzyl azide With copper(I) oxide In water at 60℃; for 0.333333h; Stage #2: Huisgen Cycloaddition; regioselective reaction;	96%
With [(1-phenylisoquinoline)2Ir(acetylacetonate)] In dichloromethane at 20℃; Irradiation; regioselective reaction;	95%

1-ethyl-4-ethynylbenzene (40307-11-7) + 1,2-diamino-benzene (95-54-5) → C16H14N2O

Conditions	Yield
With oxygen; potassium carbonate; copper(l) chloride In methanol; acetonitrile at 25℃; for 2h; Irradiation; Green chemistry;	97%

1,1,1-trifluoroacetophenone (434-45-7) + 1-ethyl-4-ethynylbenzene (40307-11-7) → C18H15F3O

Conditions	Yield
With copper(I) oxide; potassium phosphate tribasic trihydrate In 1-methyl-pyrrolidin-2-one at 50℃; for 24h;	97%
With copper diacetate; potassium carbonate In dimethyl sulfoxide at 50℃; for 24h;	89%

1-ethyl-4-ethynylbenzene (40307-11-7) + 3-(1H-indol-3-yl)-3-oxo-propionitrile (20356-45-0) → 1-(4-ethylphenyl)-4-hydroxy-9H-carbazole-3-carbonitrile

Conditions	Yield
With tert.-butylhydroperoxide; N-Bromosuccinimide In tetrahydrofuran; water at 80℃; for 24h; regioselective reaction;	97%

1-ethyl-4-ethynylbenzene (40307-11-7) + α-bromoacetophenone (70-11-1) → C18H17N3O

Conditions	Yield
With sodium azide In water at 20℃; for 1.5h; Green chemistry;	97%

1-benzylisatin (1217-89-6) + 1-ethyl-4-ethynylbenzene (40307-11-7) + tert-butyl 2-(2-chlorophenyl)-2-diazoacetate → tert-butyl 4-(1-benzyl-3-hydroxy-2-oxoindolin-3-yl)-2-(2-chlorophenyl)-4-(4-ethylphenyl)buta-2,3-dienoate

Conditions	Yield
With YBr3; C50H71N5O3S*BrH; copper(I) bromide In chloroform at 30℃; for 3h; Inert atmosphere; stereoselective reaction;	97%

2-Iodophenol (533-58-4) + 1-ethyl-4-ethynylbenzene (40307-11-7) → 2‐(4‐ethylphenyl)benzofuran

Conditions	Yield
With potassium phosphate; C45H51Cl4N7Pd2 In dimethyl sulfoxide at 90℃; for 16h; Reagent/catalyst; Schlenk technique;	97%
With potassium phosphate; C43H36N4O4Pd In dimethylsulfoxide-d6 at 90℃; for 10h; Reagent/catalyst; Heck Reaction;	84%

1-ethyl-4-ethynylbenzene (40307-11-7) → 1-ethyl-4-(iodoethynyl)benzene

Conditions	Yield
With [bis(acetoxy)iodo]benzene; triethylamine; potassium iodide; copper(l) iodide In acetonitrile at 20℃; for 0.5h;	96%
With [bis(acetoxy)iodo]benzene; trimethylsulphonium iodide In acetonitrile at 20℃; for 0.5h; chemoselective reaction;	92%
With dmap; iodine In dichloromethane for 10h; Heating;	87%
With sodium 4-methylbenzenesulfinate; potassium iodide In ethanol at 20℃; for 12h;	82%
With tert.-butylhydroperoxide; potassium iodide In methanol at 20℃;

4-toluenesulfonyl azide (941-55-9) + N-(4-Methoxyphenyl)-3-phenylpropenaldimine (15286-52-9, 22835-33-2, 80542-40-1, 88315-63-3, 101535-86-8, 123525-44-0) + 1-ethyl-4-ethynylbenzene (40307-11-7) → (Z)-2-(4-ethylbenzylidene)-1-(4-methoxyphenyl)-4-phenyl-3-tosyl-1,2,3,4-tetrahydropyrimidine (1203703-51-8)

Conditions	Yield
With triethylamine; copper(I) bromide In toluene at 20℃; for 3h; Inert atmosphere; regioselective reaction;	96%

1-ethyl-4-ethynylbenzene (40307-11-7) + (3R,4R)-3-[(R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-acetoxyazetidin-2-one (76899-07-5, 78963-47-0, 78963-48-1, 78963-60-7, 80951-41-3, 81275-02-7, 85647-75-2, 85954-95-6, 92217-74-8, 104527-11-9, 76855-69-1) → C21H32N4O2Si (1219035-40-1)

Conditions	Yield
With copper(l) iodide; sodium azide In water at 70℃; for 3h; Inert atmosphere; stereoselective reaction;	96%

1-ethyl-4-ethynylbenzene (40307-11-7) → 4-ethylacetophenone (937-30-4)

Conditions	Yield
With silver hexafluoroantimonate In methanol; water at 120℃; for 24h; Sealed tube;	96%
With water at 60℃; for 20h; Sealed tube;	96%
With p-toluenesulfonic acid monohydrate; acetic acid In dichloromethane at 50℃; for 3h; Sealed tube;	95%

1-ethyl-4-ethynylbenzene (40307-11-7) + phenylacetylene (536-74-3) → 1-[4-(4-ethylphenyl)buta-1,3-diynyl]benzene (1402831-16-6)

Conditions	Yield
With pyrrolidine; 1-(4-nitrophenyl)-3-N,N-dimethylamino-2-propen-1-one; copper(ll) bromide In dichloromethane at 25℃; for 12h;	96%
With copper(II) bis(trifluoromethanesulfonate); 1,8-diazabicyclo[5.4.0]undec-7-ene In acetone at 25℃; Glaser Coupling;	82%

1-ethyl-4-ethynylbenzene (40307-11-7) + 4-methoxy-aniline (104-94-9) → 2-(4-ethylphenyl)-N-(4-methoxyphenyl)-2-oxoacetamide

Conditions	Yield
With oxygen; copper(l) chloride In methanol; acetonitrile at 20℃; for 8h; Irradiation;	96%

1-ethyl-4-ethynylbenzene (40307-11-7) + 2-iodo-N-methyl-benzamide (58084-22-3) → (Z)-3-(4-ethylbenzylidene)-2-methylisoindolin-1-one

Conditions	Yield
With tetrabutylammomium bromide; caesium carbonate; triphenylphosphine; copper(l) chloride In water at 130℃; for 0.5h; Glovebox; Inert atmosphere; stereoselective reaction;	96%

1-benzyl-7-(trifluoromethyl)indoline-2,3-dione (1263090-20-5) + 1-ethyl-4-ethynylbenzene (40307-11-7) → (S)-1-benzyl-3-hydroxy-3-(4-ethylphenylethynyl)-7-trifluoromethyloxindole

Conditions	Yield
With copper(l) iodide; (S)-N-((1R,2R)-2-(diphenylphosphanyl)-cyclohexyl)-2-((4-methylphenyl)sulfonamido)-3-phenylpropanamide; triethylamine In tert-butyl methyl ether at 40℃; for 72h; Inert atmosphere; Sealed tube; enantioselective reaction;	96%
With copper(l) iodide; (S)-N-((1R,2R)-2-(diphenylphosphanyl)-cyclohexyl)-2-((4-methylphenyl)sulfonamido)-3-phenylpropanamide; triethylamine In tert-butyl methyl ether at 40℃; for 72h; Inert atmosphere; enantioselective reaction;	96%

1-ethyl-4-ethynylbenzene (40307-11-7) + 4-(bromoacetyl)toluene (619-41-0) → C19H19N3O

Conditions	Yield
With sodium azide In water at 20℃; for 1.5h; Green chemistry;	96%

1-ethyl-4-ethynylbenzene (40307-11-7) + Benzoylformic acid (611-73-4) + benzylamine (100-46-9) → 3-benzyl-5-(4-ethylbenzylidene)-4-phenyloxazolidin-2-one

Conditions	Yield
With copper(l) iodide; copper(ll) bromide In isopropyl alcohol at 100℃; for 35h; Sealed tube;	96%

Upstream product

• 937-30-4 4-ethylacetophenone 
• 25309-64-2 4-ethyl-1-iodobenzene 
• 393857-27-7 (2-(4-ethylphenyl)ethynyl)trimethylsilane 
• 7681-65-4 copper(I) iodide 
• 1066-54-2 trimethylsilylacetylene 
• 4748-78-1 4-ethylbenzylaldehyde 
• 59931-57-6 4-Ethyl-β,β'-dibromostyrene 

Downstream Products

• 639516-96-4 [5-chloro-2-(4-ethyl-phenylethynyl)-phenyl]-phosphonic acid diethyl ester 
• 639517-03-6 [2-(4-ethyl-phenylethynyl)-5-nitro-phenyl]-phosphonic acid diethyl ester 
• 1011736-38-1 1-(4-methoxybenzyl)-5-chloro-3-(2-(4-ethylphenyl)ethynyl)-6-(4-methoxyphenyl)pyrazin-2(1H)-one 
• 1032724-08-5 1-allyl-2-(2-(4-ethylphenyl)ethynyl)-4,5-dimethylbenzene 
• 1086707-55-2 C₂₂H₁₈ 
• 1383274-53-0 2-((4-ethylphenyl)ethynyl)benzaldehyde 
• 1217554-45-4 1-ethyl-4-((4-methoxyphenyl)buta-1,3-diyn-1-yl)benzene 
• 1229168-47-1 7-((4-ethylphenyl)ethynyl)-2-fluoro-6-(4-methoxybenzyl)-6,7-dihydro-5H-dibenzo[c,e]azepine 
• 1315379-41-9 3-(4-(ethyl)phenyl)-1-phenylpropan-2-yn-1-one 
• 1315379-52-2 3-(4-ethylphenyl)-2-(phenylthio)-1H-inden-1-one 
• 1369593-24-7 3-(4-ethylphenyl)-1-phenylpropynol 
• 1310052-28-8 3β-acetoxy-16β-[4-(4-ethylphenyl)-1H-1,2,3-triazol-1-ylmethyl]androst-5-en-17β-ol 
• 1310052-15-3 16β-[4-(4-ethylphenyl)-1H-1,2,3-triazol-1-ylmethyl]androst-5-ene-3β,17β-diol 

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