103-63-9

Basic information

• Product Name: (2-Bromoethyl)benzene
• Synonyms: 1-BROMO-2-PHENYLETHANE;PHENYL ETHYL BROMIDE;PHENETHYL BROMIDE;(2-bromoethyl)-benzen;.beta.-Phenylethylbromide;2-Phenethyl bromide;2-phenethylbromide;2-Phenyl-1-bromoethane
• CAS NO: 103-63-9
• Molecular Formula: C₈H₉Br
• Molecular Weight: 185.06
• EINECS: 203-130-8
• Product Categories: fine chemicals
• Mol File: 103-63-9.mol
• Article Data: 128

Chemical Properties

• Melting Point: -56 °C
• Boiling Point: 220-221 °C(lit.)
• Flash Point: 193 °F
• Appearance: Clear colorless to pale yellow/Liquid
• Density: 1.355 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.167mmHg at 25°C
• Refractive Index: n20/D 1.556(lit.)
• Storage Temp.: 2-8°C
• Solubility: 0.039g/l
• Water Solubility: INSOLUBLE
• Stability: Stable. Incompatible with strong oxidizing agents.
• BRN: 507487
• CAS DataBase Reference: (2-Bromoethyl)benzene(CAS DataBase Reference)
• NIST Chemistry Reference: (2-Bromoethyl)benzene(103-63-9)
• EPA Substance Registry System: (2-Bromoethyl)benzene(103-63-9)

Safety Data

• Hazard Codes: Xn
• Statements: 22-36-36/37/38
• Safety Statements: 26-37/39-39
• RIDADR: UN 1993 / PGIII
• WGK Germany: 3
• RTECS: CY9032000
• TSCA: Yes
• Hazardous Substances Data: 103-63-9(Hazardous Substances Data)

Usage

Description

Phenethylbromide is an analytical reference material that is structurally categorized as an organobromide. It is used in the synthesis of a variety of compounds, including fentanyl. Phenethylbromide is combined with 4-piperidinone to produce N-phenethyl-4-piperidone, which, as a precursor in the synthesis of fentanyl (Item Nos. ISO60197 | 14719), is scheduled as a List I chemical in the United States. Phenethylbromide may be found as in impurity in samples of fentanyl produced using this pathway.

Chemical Properties

colourless to yellow liquid. It is miscible with ether and benzene, but insoluble in water.

Uses

(2-Bromoethyl)benzene is used in the preparation of phenelzine by reacting with hydrazine. It is also used as a starting material to prepare various beta-phenethyl derivatives, active pharmaceutical ingredients, and fragrances. It finds application as a flame retardant.

Preparation

(2-Bromoethyl)benzene is synthesized by the reaction of phenethyl alcohol with hydrogen bromide.Reaction: The phenethyl alcohol was heated to 110°C, hydrogen bromide was slowly introduced, and the reaction was refluxed. The reaction was completed, cooled, washed with water, 10% sodium carbonate solution, and water in turn. After drying with anhydrous potassium carbonate, fractional distillation under reduced pressure was carried out to collect fractions at 97-99°C (2.0 kPa) with a yield of over 90%.

Synthesis Reference(s)

The Journal of Organic Chemistry, 29, p. 2317, 1964 DOI: 10.1021/jo01031a051Synthetic Communications, 20, p. 2349, 1990 DOI: 10.1080/00397919008053179

Synthesis

Phenethylbromide is usually manufactured by the free-radical addition of HBr to styrene.The typical batch process is run in a glasslined reactor by sparging gaseous HBr through a solution of styrene in an inert solvent containing a free-radical initiator. The reaction, which is rapid and moderately exothermic, can be controlled by introducing HBr at about the rate it is consumed. When styrene is completely converted, any excess HBr that is present can be recovered by various techniques prior to recovery of solvent and product by distillation.

Purification Methods

Wash the bromide with conc H2SO4, water, aqueous 10% Na2CO3 and water again, then dry it with CaCl2 and fractionally distil it just before use. [Beilstein 5 IV 907.]

InChI:InChI=1/C8H9Br/c9-7-6-8-4-2-1-3-5-8/h1-5H,6-7H2

Synthetic route

2-phenylethanol (60-12-8) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With hydrogen bromide; Aliquat 336 In chlorobenzene at 85℃; without cat.;	98.7%
With 1,2-dibromo-1,1,2,2-tetrachloroethane; triphenylphosphine In dichloromethane at 20℃; for 0.15h; Appel Halogenation;	97%
With Silphos; bromine In acetonitrile for 0.416667h; Heating;	96%

2-phenylethyl mesylate (20020-27-3) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With 1-n-butyl-3-methylimidazolim bromide at 50℃; for 1h; Inert atmosphere; Green chemistry;	97%
With lithium bromide In tetrahydrofuran Inert atmosphere; Reflux;	94%

ethylbenzene (100-41-4) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With 2,4,4,6-Tetrabromo-2,5-cyclohexadien-1-one; silica gel for 4h; UV-irradiation;	94%
With dihydrogen peroxide; bromine In dichloromethane; water for 4h; Reagent/catalyst; Reflux;	92%

1-fluoro-2-phenylethane (458-87-7) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With boron tribromide In dichloromethane at 0℃; for 0.0833333h;	91%
With aluminum tri-bromide In chlorobenzene at 20℃; for 1h;

(2-(methoxymethoxy)ethyl)benzene (54673-12-0) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With phosphotungstic acid; tetrabutylammomium bromide at 130 - 142℃; for 0.0333333h; Microwave irradiation; Ionic liquid; chemoselective reaction;	90%
With tetrabutylammomium bromide; 1-(n-butyl)-3-methylimidazolium tetrachloroindate at 135 - 140℃; for 0.0666667h; Microwave irradiation; Neat (no solvent); chemoselective reaction;	83%

4-(4-Chloro-phenyl)-1-phenethyl-2,3,5,6-tetraphenyl-pyridinium; bromide (76192-15-9) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With 2,4,6-triphenylpyridine at 180 - 220℃; under 0.5 - 1.5 Torr;	75%

4,4,5,5-tetramethyl-2-phenethyl-1,3,2-dioxaborolane (165904-22-3) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With trimethylsilyl trifluoromethanesulfonate; 2-methoxybenzo[d][1,3,2]dioxaborole; benzenesulfonyl bromide In methanol; dichloromethane; benzene at 70℃; for 16h; Inert atmosphere;	75%

2-phenylethanol (60-12-8) + triphenylphosphine (603-35-0) → 1-phenyl-2-bromoethane (103-63-9) + Triphenylphosphine oxide (791-28-6)

Conditions	Yield
With carbon tetrabromide In 1,2-dichloro-ethane	A 72% B n/a

2-phenylethyl mesylate (20020-27-3) → styrene (292638-84-7) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With lithium bromide In N,N-dimethyl-formamide at 120℃; Inert atmosphere;	A 17% B 72%

C22H17NO + allyl bromide (106-95-6) → 3,5-diphenyl-4-(2-propen-1-yl)isoxazole (1227781-92-1) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With tetrabutylammomium bromide; palladium diacetate In N,N-dimethyl-formamide at 80℃; for 1h;	A 68% B 65 %Spectr.

1-p-Toluolsulfonyl-1-phenethyl-hydrazin (159690-31-0) → toluene-p-sulfonyl bromide (1950-69-2) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With N-Bromosuccinimide In tetrahydrofuran for 16h; Ambient temperature; Irradiation;	A n/a B 67%

2-phenylethanol (60-12-8) → dibenzyl ether (103-50-4) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
Stage #1: 2-phenylethanol With N,N-dimethylthiourea In dichloromethane at 20℃; Stage #2: With N-Bromosuccinimide In dichloromethane at 20℃; for 2h;	A n/a B 64%

1-Phenethyl-2,3,4,5,6-pentaphenyl-pyridinium; bromide (71017-60-2) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With 2,4,6-triphenylpyridine at 180 - 220℃; under 0.5 - 2 Torr;	60%

toluene (108-88-3) + 1,2-dibromomethane (74-95-3) → 1,3-diphenylpropane (1081-75-0) + 1-phenyl-2-bromoethane (103-63-9) + 1,1'-(1,2-ethanediyl)bisbenzene (103-29-7)

Conditions	Yield
Stage #1: toluene With n-butyllithium In tetrahydrofuran; hexane at 20℃; for 3h; Inert atmosphere; Schlenk technique; Stage #2: 1,2-dibromomethane In tetrahydrofuran; hexane at 20℃; Inert atmosphere; Schlenk technique;	A 1% B n/a C n/a

styrene (292638-84-7) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With dilauryl peroxide; hydrogen bromide; pentane
With ethylbenzene; hydrogen bromide; dibenzoyl peroxide at 95℃;
With hydrogen bromide; nickel; Petroleum ether

bromocyane (506-68-3) + N,N-diethylphenethylamine (5300-21-0) → ethyl bromide (74-96-4) + ethyl-phenethyl-carbamonitrile (860767-75-5) + 1-phenyl-2-bromoethane (103-63-9)

2-phenethoxybenzene (40515-89-7) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With hydrogen bromide; acetic acid at 120℃;
With water; boron tribromide In dichloromethane at 20℃; for 0.5h; Inert atmosphere;	98 %Chromat.

5,8-Dibrom-1,3-cyclooctadien (53800-00-3) → (1-bromoethyl)benzne (585-71-7, 38661-81-3) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
under 760 Torr; Erhitzen auf Siedetemperatur;

styrene oxide (96-09-3) → 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With chloro-trimethyl-silane; 1,1,3,3-Tetramethyldisiloxane; lithium bromide 1.) dry acetonitrile, 5-10 deg C, 2-3 min, 2.) reflux, 15 min; Yield given. Multistep reaction;
With chloro-trimethyl-silane; 1,1,3,3-Tetramethyldisiloxane; lithium bromide 1.) trifluoroacetic acid, 2.) 50 deg C, 15 h; Yield given. Multistep reaction;

ethylbenzene (100-41-4) → 2-phenylethyl chloride (622-24-2) + 1-phenyl-2-bromoethane (103-63-9)

Conditions	Yield
With bromine; chlorine In various solvent(s) Irradiation;
With bromine; chlorine In various solvent(s) Product distribution; Irradiation; hidrogen selectivity in various photoinitiated halogenations;

1-phenyl-2-bromoethane (103-63-9) → phenethyl azide (6926-44-9)

Conditions	Yield
With sodium azide In N,N-dimethyl-formamide at 80℃;	100%
With sodium azide In N,N-dimethyl-formamide at 80℃; for 24h; Inert atmosphere;	100%
With sodium azide In N,N-dimethyl-formamide at 85℃;	100%

diphenyl diselenide (1666-13-3) + 1-phenyl-2-bromoethane (103-63-9) → (2-phenyl-ethyl) phenyl selenide (65275-36-7)

Conditions	Yield
With sodium tetrahydroborate In ethanol for 2h; Ambient temperature;	100%
With zinc In N,N-dimethyl-formamide at 100℃; for 2h; Inert atmosphere;	94%
With indium iodide In dichloromethane at 20℃; for 1h;	89%
With sodium tetrahydroborate In ethanol; 1,2-dichloro-ethane at 20℃; Reduction; alkylation;	79%
With triphenylphosphine; 1-pentyl-3-methylimidazolium bromide at 75℃; for 5.5h;	75%

potassium tert-butylate (865-47-4) + 1-phenyl-2-bromoethane (103-63-9) → styrene (292638-84-7)

Conditions	Yield
In tert-butyl alcohol at 40℃; Rate constant; Mechanism; secondary α-deuterium isotope effects investigated;	100%

1-phenyl-2-bromoethane (103-63-9) + SynPhase lantern-OC(O)-C6H4-(NC(O)C6H4NHC(S)) → 4-(4-oxo-2-phenethylsulfanyl-4H-quinazolin-3-yl)-benzoic acid

Conditions	Yield
Stage #1: 1-phenyl-2-bromoethane; SynPhase lantern-OC(O)-C6H4-(NC(O)C6H4NHC(S)) With 1-methyl-pyrrolidin-2-one; N-ethyl-N,N-diisopropylamine at 20℃; for 16h; Stage #2: With water; trifluoroacetic acid at 20℃; for 1h;	100%

heptanethiol (1639-09-4) + 1-phenyl-2-bromoethane (103-63-9) → (2-heptylsulfanyl-ethyl)-benzene

Conditions	Yield
Stage #1: heptanethiol With tetra-(n-butyl)ammonium iodide; caesium carbonate In N,N-dimethyl-formamide at 20℃; for 1h; Stage #2: 1-phenyl-2-bromoethane In N,N-dimethyl-formamide at 0 - 20℃; for 1h;	100%

1-phenyl-2-bromoethane (103-63-9) + 2,2-dimethyl-propionic acid 4-(2-phthalimido-ethyl)-imidazol-1-ylmethyl ester (51721-15-4) → 1-pivaloyloxymethyl-3-(4-phenylethyl)-4-(2-phthalimidoethyl)imidazolium bromide (281197-46-4)

Conditions	Yield
In acetonitrile for 72h; Heating / reflux;	100%

1-methyl-1H-imidazole (616-47-7) + 1-phenyl-2-bromoethane (103-63-9) → 1-methyl-3-(2-phenylethyl)imidazolium bromide

Conditions	Yield
at 140℃; Continuous flow; neat (no solvent);	100%
In acetonitrile for 18h; Reflux; Schlenk technique;	86%
In toluene for 24h; Reflux; Inert atmosphere;
In toluene for 24h; Reflux; Inert atmosphere;

2,6-dimethylphenyl isonitrile (119072-54-7, 2769-71-3) + 2,6-diisopropylphenyl isocyanate (28178-42-9) + 1-phenyl-2-bromoethane (103-63-9) → N-(2,6-diisopropylphenyl)-2-(2,6-dimethylphenylimino)-4-phenylbutanamide (1392826-44-6)

Conditions	Yield
Stage #1: 2,6-dimethylphenyl isonitrile; 1-phenyl-2-bromoethane With N,N,N,N,N,N-hexamethylphosphoric triamide; samarium diiodide In tetrahydrofuran at -15℃; for 3h; Stage #2: 2,6-diisopropylphenyl isocyanate In tetrahydrofuran at -78℃;	100%

2,6-dimethylphenyl isonitrile (119072-54-7, 2769-71-3) + phenyl isocyanate (103-71-9) + 1-phenyl-2-bromoethane (103-63-9) → 2-(2,6-dimethylphenylamino)-N,4-diphenylbutanamide (1392826-54-8)

Conditions	Yield
Stage #1: 2,6-dimethylphenyl isonitrile; 1-phenyl-2-bromoethane With N,N,N,N,N,N-hexamethylphosphoric triamide; samarium diiodide In tetrahydrofuran at -15℃; for 3h; Stage #2: phenyl isocyanate In tetrahydrofuran at -78℃; for 0.5h;	100%

2,6-dimethylphenyl isonitrile (119072-54-7, 2769-71-3) + phenyl isocyanate (103-71-9) + 1-phenyl-2-bromoethane (103-63-9) → 2-(2,6-dimethylphenylimino)-N,4-diphenylbutanamide (1392826-40-2)

Conditions	Yield
Stage #1: 2,6-dimethylphenyl isonitrile; 1-phenyl-2-bromoethane With N,N,N,N,N,N-hexamethylphosphoric triamide; samarium diiodide In tetrahydrofuran at -15℃; for 3h; Stage #2: phenyl isocyanate In tetrahydrofuran at -78℃;	100%

2,6-dimethylphenyl isonitrile (119072-54-7, 2769-71-3) + 4-Methoxyphenyl isocyanate (5416-93-3) + 1-phenyl-2-bromoethane (103-63-9) → 2-(2,6-dimethylphenylimino)-N-(4-methoxyphenyl)-4-phenylbutanamide (1392826-41-3)

Conditions	Yield
Stage #1: 2,6-dimethylphenyl isonitrile; 1-phenyl-2-bromoethane With N,N,N,N,N,N-hexamethylphosphoric triamide; samarium diiodide In tetrahydrofuran at -15℃; for 3h; Stage #2: 4-Methoxyphenyl isocyanate In tetrahydrofuran at -78℃;	100%

phenyltin trichloride (1124-19-2) + 1-phenyl-2-bromoethane (103-63-9) → tri(2-phenylethyl)(phenyl)stannane (97664-42-1)

Conditions	Yield
Stage #1: 1-phenyl-2-bromoethane With iodine; magnesium In diethyl ether Inert atmosphere; Reflux; Stage #2: phenyltin trichloride In diethyl ether; n-heptane at 0 - 20℃; Inert atmosphere;	100%

1-phenyl-2-bromoethane (103-63-9) + ortho-bromobenzaldehyde (6630-33-7) → 1-(2-bromophenyl)-3-phenylpropan-1-ol

Conditions	Yield
Stage #1: 1-phenyl-2-bromoethane With iodine; magnesium In tetrahydrofuran at 50℃; for 1h; Inert atmosphere; Stage #2: ortho-bromobenzaldehyde In tetrahydrofuran for 4h; Inert atmosphere; Reflux;	100%

carbon dioxide (124-38-9) + 1-phenyl-2-bromoethane (103-63-9) → diphenethyl carbonate (67879-62-3)

Conditions	Yield
With caesium carbonate In acetonitrile at 80℃; under 760.051 Torr; for 18h; Temperature;	99.5%

1-phenyl-2-bromoethane (103-63-9) + 1-benzylnicotinium bromide → C25H30N2(2+)*2I(1-)

Conditions	Yield
In diethylene glycol dimethyl ether; acetonitrile for 8h; Heating;	99.1%

1-phenyl-2-bromoethane (103-63-9) + 1-(2-ethoxyethyl)-2-(1-piperazinyl)-1H-benzimidazole (87233-69-0) → 1-(2-Ethoxy-ethyl)-2-(4-phenethyl-piperazin-1-yl)-1H-benzoimidazole (101954-16-9)

Conditions	Yield
With potassium carbonate In ethanol at 65℃; for 5h;	99%

1-phenyl-2-bromoethane (103-63-9) + triphenylphosphine (603-35-0) → (2-phenylethyl)triphenylphosphonium bromide (53213-26-6)

Conditions	Yield
at 100℃; for 2h; Addition;	99%
In neat (no solvent) at 120℃; for 22h;	99%
In benzene for 24h; Heating;	92%

1-phenyl-2-bromoethane (103-63-9) + β-naphthaldehyde (66-99-9) → 2,2,2-tris(methylthio)-1-(2-naphthyl)ethanol (170654-26-9)

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 2h;	99%

1-phenyl-2-bromoethane (103-63-9) + pyridine-3,4-dicarboxylic acid diisopropyl ester → 4-phenethyl-1,4-dihydro-pyridine-3,4-dicarboxylic acid diisopropyl ester

Conditions	Yield
Stage #1: pyridine-3,4-dicarboxylic acid diisopropyl ester With ammonia; sodium In tetrahydrofuran at -78℃; for 0.25h; Stage #2: 1-phenyl-2-bromoethane In tetrahydrofuran for 10h;	99%

1-phenyl-2-bromoethane (103-63-9) → α-bromoacetophenone (70-11-1)

Conditions	Yield
With Iron(III) nitrate nonahydrate; 1-hydroxy-pyrrolidine-2,5-dione; oxygen In benzonitrile at 90℃; for 20h;	99%
With 3,6-bis(triphenylphosphonium)cyclohexene peroxodisulfate In water; acetonitrile for 0.416667h; Heating;	84%
With 1,4-bis(triphenylphosphonium)butane cerium nitrate In water; acetic acid for 0.833333h; Reflux;	75%
With oxygen; Langlois reagent In acetonitrile at 25℃; under 760.051 Torr; for 12h; Irradiation; Green chemistry;	98 %Chromat.

1-phenyl-2-bromoethane (103-63-9) + diphenylphosphane (829-85-6) → (2-phenylethyl)diphenylphosphane (5952-49-8)

Conditions	Yield
With cesium hydroxide; 4 Angstroem MS In N,N-dimethyl-formamide at 23℃; for 29h;	99%

1-phenyl-2-bromoethane (103-63-9) + phenylacetylene (536-74-3) → 1-phenethyl-4-phenyl-1H-[1,2,3]triazole

Conditions	Yield
With sodium azide In ethanol at 80℃; for 8h; regioselective reaction;	99%
With sodium azide In ethanol at 80℃; for 8h;	98%
With sodium azide In water at 60℃; for 5h; Temperature; Green chemistry; regioselective reaction;	97%

2,5-dimethoxythiophenol (1483-27-8) + 1-phenyl-2-bromoethane (103-63-9) → 1,4-dimethoxy-2-(2-phenethyl)thiobenzene (849919-63-7)

Conditions	Yield
Stage #1: 2,5-dimethoxythiophenol With potassium hydroxide In methanol for 1h; Stage #2: 1-phenyl-2-bromoethane In methanol for 0.5h; Heating;	99%

chlorodiisopropylsilane (2227-29-4) + 1-phenyl-2-bromoethane (103-63-9) → diisopropyl(phenethyl)silane

Conditions	Yield
Stage #1: 1-phenyl-2-bromoethane With iodine; magnesium In tetrahydrofuran at 20℃; for 1h; Inert atmosphere; Stage #2: chlorodiisopropylsilane In tetrahydrofuran for 18h; Reflux; Inert atmosphere;	99%

1-phenyl-2-bromoethane (103-63-9) → N-phenylethylhydroxylamine (3217-93-4)

Conditions	Yield
With hydroxylamine monohydrate In methanol at 100℃; under 18100.7 Torr; for 0.166667h; Flow reactor; chemoselective reaction;	99%

2-bromothiophenol (6320-02-1) + 1-phenyl-2-bromoethane (103-63-9) → (2-bromophenyl)(phenethyl)sulfane

Conditions	Yield
Stage #1: o-bromothiophenol With sodium hydride; potassium carbonate In tetrahydrofuran; N,N-dimethyl-formamide at 0℃; for 0.333333h; Stage #2: 1-phenyl-2-bromoethane In tetrahydrofuran; N,N-dimethyl-formamide at 0 - 20℃;	99%

Upstream product

• 60-12-8 Phenethyl alcohol 

Downstream Products

• 5321-49-3 1-(2-PHENYLETHYL)PIPERAZINE 
• 1592-20-7 4-Vinylbenzyl chloride 
• 93-56-1 1-Phenyl-1,2-ethanediol 
• 589-08-2 N-METHYLPHENETHYLAMINE 

Recommend Products

• 6908-75-4  N-(2-phenylethyl)pyrrolidine 
• 123-75-1  pyrrolidine 
• 46346-12-7  N-(2-phenethyl)morpholine 
• 110-91-8  morpholine 
• 6324-18-1  1-(2-phenylethyl)pyridinium bromide 
• 110-86-1  pyridine 
• 18065-78-6  1-phenethylpyridin-2(1H)-one 
• 109-06-8  α-picoline 
• 10551-21-0  2-methyl-1-phenethyl-pyridinium; bromide 
• 108-89-4  picoline 
• 18097-01-3  3-hydroxy-1-phenethyl-pyridinium; bromide 
• 109-00-2  3-HYDROXYPYRIDINE 
• 108872-14-6  3-bromo-1-phenethyl-pyridinium; bromide 
• 626-55-1  3-Bromopyridine 

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