821-06-7

Basic information

• Product Name: (E)-1,4-Dibromobut-2-ene
• Synonyms: 1,4-DIBROMO-2-PENTENE;(2E)-1,4-Dibromo-2-butene;(E)-1,4-Dibromo-2-butene;1,4-Dibromo-2-butene, E;1,4-trans-Dibromobutene-2;2-Butene, 1,4-dibromo-, trans-;4-dibromo-(e)-2-buten;4-dibromo-trans-2-buten
• CAS NO: 821-06-7
• Molecular Formula: C₄H₆Br₂
• Molecular Weight: 213.9
• EINECS: 212-472-7
• Product Categories: Alkenyl;Halogenated Hydrocarbons;Organic Building Blocks;aliskiren;medical intermediates
• Mol File: 821-06-7.mol
• Article Data: 12

Chemical Properties

• Melting Point: 48-51 °C(lit.)
• Boiling Point: 205 °C(lit.)
• Flash Point: 113°C
• Appearance: colorless to slightly brown/Crystals or Crystalline Powder
• Density: 1.9393 (estimate)
• Refractive Index: 1.5361 (estimate)
• Storage Temp.: Refrigerator
• Solubility: Chloroform (Slightly), Methanol (Slightly)
• Water Solubility: slightly soluble
• Stability: Light Sensitive
• BRN: 1719696
• CAS DataBase Reference: (E)-1,4-Dibromobut-2-ene(CAS DataBase Reference)
• NIST Chemistry Reference: (E)-1,4-Dibromobut-2-ene(821-06-7)
• EPA Substance Registry System: (E)-1,4-Dibromobut-2-ene(821-06-7)

Safety Data

• Hazard Codes: T,C
• Statements: 25-34-23/25
• Safety Statements: 26-36/37/39-45-28A
• RIDADR: UN 2923 8/PG 2
• WGK Germany: 2
• RTECS: EM4725000
• F: 8-19
• HazardClass: 6.1(b)
• PackingGroup: III
• Hazardous Substances Data: 821-06-7(Hazardous Substances Data)

Usage

Chemical Properties

white to light yellow crystal powde

Uses

(2E)-1,4-Dibromo-2-butene, is used as a reagent in the preparation of diaminoalkenes though copper-mediated diamination reaction.

Synthesis Reference(s)

The Journal of Organic Chemistry, 36, p. 3324, 1971 DOI: 10.1021/jo00821a012

Air & Water Reactions

(E)-1,4-Dibromobut-2-ene may be sensitive to exposure to light and air. Insoluble in water.

Reactivity Profile

(E)-1,4-Dibromobut-2-ene is incompatible with strong oxidizers and strong bases.

Fire Hazard

(E)-1,4-Dibromobut-2-ene is probably combustible.

Purification Methods

Crystallise the dibromide from ligroin and/or distil it in a vacuum. [Beilstein 1 IV 79.]

InChI:InChI=1/C4H6Br2/c5-3-1-2-4-6/h1-2H,3-4H2/b2-1+

Synthetic route

buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With bromine In chloroform at -78 - 23℃;	100%
With bromine In tetrachloromethane at -78 - 20℃; for 16h;	58%
With bromine In tetrachloromethane at -78 - 20℃; for 16h;	58%

allyl bromide (106-95-6) → cis-1,4-dibromo-2-butene (18866-73-4) + (E)-1,4-dibromobutene (821-06-7) + ethene (74-85-1)

Conditions	Yield
With Hoveyda-Grubbs catalyst second generation In acetone at 25℃; for 1h; Grubbs Olefin Metathesis; Flow reactor; Overall yield = > 95 %;	A n/a B 95% C n/a

(E)-2-butene-1,4-diol (821-11-4) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With phosphorus tribromide	65%

s-butyl bromide (78-76-2, 5787-31-5) → (E/Z)-crotyl bromide (4784-77-4, 29576-14-5, 39616-19-8) + 2,3-dibromobutane (5408-86-6) + (E)-1,4-dibromobutene (821-06-7) + 2,2-dibromobutane (50341-35-0)

Conditions	Yield
With hydrogen bromide; bromine at 100℃; under 80 Torr; for 0.25h; Heating; Irradiation; Further byproducts given;	A 8.5% B 6.3% C 39.7% D 22.5%
With bromine at 100℃; under 80 Torr; for 0.25h; Heating; Irradiation; Further byproducts given;	A 20.3% B 3.9% C 31% D 34.6%

s-butyl bromide (78-76-2, 5787-31-5) → (E/Z)-crotyl bromide (4784-77-4, 29576-14-5, 39616-19-8) + (E)-1,4-dibromobutene (821-06-7) + 2,2-dibromobutane (50341-35-0) + 1,3-dibromobutane (107-80-2)

Conditions	Yield
With hydrogen bromide; bromine at 100℃; under 80 Torr; for 0.25h; Heating; Irradiation; Further byproducts given;	A 14.6% B 39.1% C 21.6% D 2.5%

pyridine perbromide (6081-86-3) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6) + N-(4-bromo-1-buten-3-yl)pyridinium bromide (76665-61-7)

Conditions	Yield
In 1,2-dichloro-ethane at 20℃; for 0.5h; Yields of byproduct given;	A n/a B n/a C 35%

s-butyl bromide (78-76-2, 5787-31-5) → 2,3-dibromobutane (5408-86-6) + (E)-1,4-dibromobutene (821-06-7) + 2,2-dibromobutane (50341-35-0) + 1,2,3,4-tetrabromobutane (1529-68-6)

Conditions	Yield
With bromine at 100℃; under 80 Torr; for 0.25h; Heating; Irradiation; Further byproducts given;	A 10.2% B 24% C 24% D 9%

s-butyl bromide (78-76-2, 5787-31-5) → 2,3-dibromobutane (5408-86-6) + (E)-1,4-dibromobutene (821-06-7) + 2,2-dibromobutane (50341-35-0) + 1,2,3-tribromobutane (632-05-3)

Conditions	Yield
With hydrogen bromide; bromine at 100℃; under 80 Torr; for 0.25h; Heating; Irradiation; Further byproducts given;	A 13.7% B 19.2% C 23.8% D 12.5%

allyl bromide (106-95-6) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidine][benzylidene]ruthenium(II) dichloride In dichloromethane for 0.183333h; Inert atmosphere;	15%

decane (124-18-5) + 3,4-dibromo-1-butene (10463-48-6) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
at 61 - 100℃; Kinetics;
at 61 - 100℃; Mechanism;

cis-1,4-dibromo-2-butene (18866-73-4) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
in der Waerme;
at 120℃;

3,4-dibromo-1-butene (10463-48-6) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
at 85 - 90℃;

buta-1,3-diene (106-99-0) → 1,4-dibromo-2-butene (6974-12-5) + (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With bromine liquid 1,4-dibromo-butene-(2);
With chloroform; bromine

buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
With bromine In 1,2-dichloro-ethane at 25℃; for 0.333333h; Mechanism; Product distribution; Rate constant; other solvent and other brominating agent;
With hexane; bromine at -30 - -15℃;

1,4-butenediol (821-11-4, 6117-80-2, 110-64-5) → cis-1,4-dibromo-2-butene (18866-73-4) + (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With phosphorus tribromide In tetrachloromethane

pyridine (110-86-1) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6) + N-(4-bromo-1-buten-3-yl)pyridinium bromide (76665-61-7)

Conditions	Yield
With bromine In 1,2-dichloro-ethane at 25℃; for 0.5h; Mechanism; Product distribution; Rate constant; other solvent, other brominating agent;

bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
in der Gasphase bei Verduennung mit Stickstoff;

chloroform (67-66-3) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
at -30 - -15℃;

carbon disulfide (75-15-0) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
das Mengenverhaeltnis der Reaktionsprodukte ist vom Loesungsmittel unabhaengig;

tetrachloromethane (56-23-5) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
das Mengenverhaeltnis der Reaktionsprodukte ist vom Loesungsmittel unabhaengig;

hexane (110-54-3) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
das Mengenverhaeltnis der Reaktionsprodukte ist vom Loesungsmittel unabhaengig;

chloroform (67-66-3) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
das Mengenverhaeltnis der Reaktionsprodukte ist vom Loesungsmittel unabhaengig;

Trichloroethylene (79-01-6) + bromine (7726-95-6) + buta-1,3-diene (106-99-0) → (E)-1,4-dibromobutene (821-06-7) + 3,4-dibromo-1-butene (10463-48-6)

Conditions	Yield
das Mengenverhaeltnis der Reaktionsprodukte ist vom Loesungsmittel unabhaengig;

cis-butene-1,4-diol (344397-18-8) → (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With pyridine; phosphorus tribromide; iodine In (2S)-N-methyl-1-phenylpropan-2-amine hydrate; dichloromethane

allyl bromide (106-95-6) → cis-1,4-dibromo-2-butene (18866-73-4) + (E)-1,4-dibromobutene (821-06-7)

Conditions	Yield
With Hoveyda-Grubbs catalyst second generation In dichloromethane Inert atmosphere; Overall yield = 15 percent; Overall yield = 1.7 g;	A n/a B n/a

N,N'-dimethylbenzylamine (103-83-3) + (E)-1,4-dibromobutene (821-06-7) → C22H32N2(2+)*2Br(1-) (100186-76-3)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	100%

3-hydroxypyridine-2-thione (23003-22-7) + (E)-1,4-dibromobutene (821-06-7) → 3-hydroxy-2-(4-bromo-2-buten-1-ylthio)pyridine hydrobromide

Conditions	Yield
In acetone at 20℃; for 20h;	100%

(E)-1,4-dibromobutene (821-06-7) + (S)-3-((2-hydroxynaphthalen-1-yl)methyleneamino)-4-isopropyl-2-oxazolidinone (1187455-33-9) → (S)-3-(((2-(E)-4-bromobut-2-enyloxy)naphthalen-1-yl)methyleneamino)-4-isopropyl-2-oxazolidinone (1187455-06-6)

Conditions	Yield
With potassium carbonate In acetone at 20℃; for 10h; Inert atmosphere;	100%

(E)-1,4-dibromobutene (821-06-7) + (R)-3-((2-hydroxynaphthalen-1-yl)methyleneamino)-4-isopropyl-2-oxazolidinone (1187455-34-0) → (R)-3-(((2-(E)-4-bromobut-2-enyloxy)naphthalen-1-yl)methyleneamino)-4-isopropyl-2-oxazolidinone (1187455-07-7)

Conditions	Yield
With potassium carbonate In acetone at 20℃; for 10h; Inert atmosphere;	100%

1,3-di(4-pyridyl)propane (17252-51-6) + (E)-1,4-dibromobutene (821-06-7) → C30H34N4(2+)*2Br(1-)

Conditions	Yield
In acetone at 20℃;	100%

(E)-1,4-dibromobutene (821-06-7) + acetylacetone (123-54-6) → 1-(2-methyl-5-vinyl-4,5-dihydrofuran-3-yl)ethan-1-one (75822-61-6, 115580-34-2)

Conditions	Yield
Stage #1: acetylacetone With caesium carbonate In dimethyl sulfoxide at 20℃; for 0.333333h; Claisen Rearrangement; Inert atmosphere; Stage #2: (E)-1,4-dibromobutene In dimethyl sulfoxide at 100℃; for 12h; Inert atmosphere;	100%

(E)-1,4-dibromobutene (821-06-7) + 1‐octyl‐1,4‐diazabicyclo[2.2.2]octan‐1‐ium bromide → C32H64N4(4+)*4Br(1-)

Conditions	Yield
In N,N-dimethyl-formamide for 48h; Heating;	100%

(E)-1,4-dibromobutene (821-06-7) + diethyllaurylamine (4271-27-6) → C36H76N2(2+)*2Br(1-) (100186-80-9, 110282-54-7)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	99%

(E)-1,4-dibromobutene (821-06-7) + N-(tert-butyloxycarbonyl)(2,4,6-triisopropylphenyl)sulfonamide (335004-12-1) → (E)-N,N'-bis(tert-butyloxycarbonyl)-N,N'-bis[(2,4,6-triisopropylphenyl)sulfonyl]-2-butene-1,4-diamine (335004-20-1)

Conditions	Yield
With potassium carbonate In acetonitrile Heating;	99%

(E)-1,4-dibromobutene (821-06-7) + triethyl phosphite (122-52-1) → tetraethyl (E)-2-butene-1,4-diphosphonate (1112-96-5, 16626-80-5, 56727-14-1)

Conditions	Yield
for 5h; Reflux;	99%
for 5h; Reflux;	99%
Arbuzov reaction;

4-tert-butylpyridine (3978-81-2) + (E)-1,4-dibromobutene (821-06-7) → 1,4-bis(4-tert-butylpyridinium)-but-(2E)-ene-1,4-diyl dibromide

Conditions	Yield
In N,N-dimethyl-formamide at 70℃;	99%
In N,N-dimethyl-formamide at 70℃;	66%

(E)-1,4-dibromobutene (821-06-7) + N,N-dimethylhexadecylamine (112-69-6) → C40H84N2(2+)*2Br(1-) (87673-96-9, 94941-64-7, 94941-68-1)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	98%

(E)-1,4-dibromobutene (821-06-7) + trans-6-(4-methylphenylsulfonyl)amino-4-methyl-1-triisopropyl-silyl(oxy)-cyclohex-1-ene (124603-50-5, 124603-57-2) → E-6-N,N'-<(4-methylphenylsulfonyl)-(4-bromo-2-butene)>amino-4-methyl-1-triisopropylsilyl(oxy)-cyclohex-1-ene

Conditions	Yield
With sodium hydride In tetrahydrofuran for 1h; Heating;	98%

pyridine-4-aldoxime (696-54-8) + (E)-1,4-dibromobutene (821-06-7) → (E)-1-(4-bromobut-2-enyl)-4-((hydroxyimino)methyl)pyridinium bromide

Conditions	Yield
In chloroform for 3h; Inert atmosphere; Reflux;	98%
In acetone for 1.5h; Heating;	95%
In acetone for 2h; Heating;	95%
In acetone for 2h; Reflux;	95%

4-amino-1,2,4-triazole (584-13-4) + (E)-1,4-dibromobutene (821-06-7) → trans-1,4-di(4-amino-1,2,4-triazolium-1N)-2-butene dibromide

Conditions	Yield
In acetonitrile for 6.5h; Reflux;	98%
In acetonitrile for 6.5h; Reflux;	98%

N-(tert-butyloxycarbonyl)-3,4-bis(dodecyloxy)benzenesulfonamide + (E)-1,4-dibromobutene (821-06-7) → C74H130N2O12S2 (1453119-87-3)

Conditions	Yield
With potassium carbonate In acetonitrile	98%

(E)-1,4-dibromobutene (821-06-7) + 4-cyanophenol (767-00-0) → (E)-4,4'-(but-2-ene-1,4-diylbis(oxy))dibenzonitrile (101716-60-3)

Conditions	Yield
With potassium carbonate In acetonitrile Reflux;	97%
With sodium ethanolate

(E)-1,4-dibromobutene (821-06-7) + Di-n-butyl-hexadecylamin (5675-43-4) → C52H108N2(2+)*2Br(1-) (100200-26-8, 110282-57-0)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	97%

(E)-1,4-dibromobutene (821-06-7) + 3-pyridinealdoxime (1193-92-6) → (E)-1,4-bis(3-hydroxyiminomethylpyridinium)but-2-ene dibromide

Conditions	Yield
In N,N-dimethyl-formamide at 100℃; for 2h;	97%

(E)-1,4-dibromobutene (821-06-7) + stearamidopropyl dimethylamine (7651-02-7) → C50H102N4O2(2+)*2Br(1-)

Conditions	Yield
With sodium hydroxide In isopropyl alcohol at 80℃; for 24h;	96.1%

(E)-1,4-dibromobutene (821-06-7) + 2-phenylthiocyclohexanone (110452-14-7) → (2S,3aR)-3a-Phenylsulfanyl-2-vinyl-2,3,3a,4,5,6-hexahydro-benzofuran

Conditions	Yield
With potassium hydride In tetrahydrofuran Ambient temperature;	96%

(E)-1,4-dibromobutene (821-06-7) + N-(tert-butyloxycarbonyl)(2-thienyl)sulfonamide → (E)-N,N'-bis(tert-butyloxycarbonyl)-N,N'-bis[(2-thienyl)sulfonyl]-2-butene-1,4-diamine (335004-26-7)

Conditions	Yield
With potassium carbonate	96%

pyridine-4-aldoxime (696-54-8) + (E)-1,4-dibromobutene (821-06-7) → (E)-1-(2-hydroxyiminomethylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene dibrobide

Conditions	Yield
In N,N-dimethyl-formamide at 100℃; for 4h;	96%
In N,N-dimethyl-formamide at 70℃;	95%
In N,N-dimethyl-formamide at 100℃; for 1.5h;	93%

(E)-1,4-dibromobutene (821-06-7) + isonicotinamide (1453-82-3) → (E)-1-(4-bromobut-2-enyl)-4-carbamoylpyridinium bromide

Conditions	Yield
In acetonitrile for 3h; Inert atmosphere; Reflux;	96%
In acetone for 2h; Heating;	93%
In acetone for 2h; Reflux;	93%

(E)-1,4-dibromobutene (821-06-7) → C4H6O6S2(2-)*2Na(1+)

Conditions	Yield
With sodium sulfite In water; N,N-dimethyl-formamide at 100℃; for 11h;	96%
With sodium sulfite In water at 105 - 115℃;

N,N-dimethyloctanamide (7378-99-6) + (E)-1,4-dibromobutene (821-06-7) → C24H52N2(2+)*2Br(1-) (56713-62-3, 110282-51-4)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	95%

N,N-dimethylaminododecane (112-18-5) + (E)-1,4-dibromobutene (821-06-7) → trans-1,4-bis(dodecyldimethylammonio)-2-butylene dibromide (100186-75-2, 108574-07-8)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	95%

(E)-1,4-dibromobutene (821-06-7) + octyldibutylamine (41145-51-1) → C36H76N2(2+)*2Br(1-) (100186-84-3, 110282-53-6)

Conditions	Yield
In acetonitrile for 0.5h; Heating;	95%

(E)-1,4-dibromobutene (821-06-7) → trans-2,3-di(bromomethyl)oxirane (14396-64-6, 50477-73-1)

Conditions	Yield
With 3-chloro-benzenecarboperoxoic acid In chloroform for 20h; Heating;	95%

Upstream product

• 7726-95-6 bromine 
• 106-99-0 buta-1,3-diene 
• 67-66-3 chloroform 
• 75-15-0 carbon disulfide 
• 56-23-5 tetrachloromethane 
• 110-54-3 hexane 
• 79-01-6 Trichloroethylene 
• 106-95-6 allyl bromide 
• 6117-80-2 1,4-butenediol 
• 344397-18-8 cis-butene-1,4-diol 
• 821-11-4 trans-butene-1,4-diol 
• 6081-86-3 pyridine perbromide 
• 78-76-2 s-butyl bromide 
• 110-86-1 pyridine 

Downstream Products

• 22805-71-6 (E)-1,4-dimethoxy-2-butene 
• 13269-52-8 trans-3-Hexene 
• 2657-67-2 (2R,3S)-1,2,3,4-Tetrabromo-butane 
• 106-99-0 buta-1,3-diene 
• 51523-45-6 hexa-N-allyl-N,N'-but-2t-enediyl-di-ammonium; dibromide 
• 7686-78-4 diethyl 2-vinylcyclopropane-1,1-dicarboxylate 
• 110-54-3 hexane 
• 19689-19-1 5-decene 
• 6728-08-1 trans-1,4-bis(phenylsulfanyl)-2-buene 
• 17208-47-8 1,4-bis-(4-chloro-phenoxy)-but-2t-ene 
• 497-06-3 3,4-butenediol 
• 821-11-4 trans-butene-1,4-diol 
• 40930-37-8 1,4-diamino-trans-2-butene 
• 38013-01-3 1,4-bis-nitrooxy-but-2t-ene 

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