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1-Bromobenzocyclobutene

Product Name
1-Bromobenzocyclobutene
CAS No.
21120-91-2
Chemical Name
1-Bromobenzocyclobutene
Synonyms
1-BrBCB;1-BROMOBENZOCYCLOBUTENE;1-Bromobenzocyclobutene 95%;1-BroMobenzocyclobutene;1-bromo-1,2-dihydrobenzocyclobutene;7-bromobicyclo[4.2.0]octa-1(6),2,4-triene;Bicyclo[4.2.0]octa-1,3,5-triene, 7-bromo-;7-BroMobicyclo[4.2.0]octa-1,3,5,7-tetraene;1-Bromobenzocyclobutene ISO 9001:2015 REACH;1-BrBCB 1-Bromobenzocyclobutene
CBNumber
CB2399465
Molecular Formula
C8H7Br
Formula Weight
183.05
MOL File
21120-91-2.mol
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1-Bromobenzocyclobutene Property

Boiling point:
90 °C/10.5 mmHg (lit.)
Density 
1.45 g/mL at 25 °C (lit.)
refractive index 
n20/D 1.59(lit.)
Flash point:
205 °F
storage temp. 
Sealed in dry,Room Temperature
Appearance
Colorless to light yellow Liquid
InChI
InChI=1S/C8H7Br/c9-8-5-6-3-1-2-4-7(6)8/h1-4,8H,5H2
InChIKey
JQOFZAWKFBCSHK-UHFFFAOYSA-N
SMILES
C12C(C(Br)C1)=CC=CC=2
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Safety

WGK Germany 
3
HS Code 
2903898090
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Hazard and Precautionary Statements (GHS)

Symbol(GHS)
Signal word
Warning
Hazard statements

H319Causes serious eye irritation

Precautionary statements

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

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N-Bromosuccinimide Price

Sigma-Aldrich
Product number
469068
Product name
1-Bromobenzocyclobutene
Purity
95%
Packaging
1g
Price
$232
Updated
2025/07/31
TRC
Product number
B488515
Product name
7-bromobicyclo[4.2.0]octa-1,3,5-triene
Packaging
100mg
Price
$240
Updated
2021/12/16
TRC
Product number
B488515
Product name
7-bromobicyclo[4.2.0]octa-1,3,5-triene
Packaging
10mg
Price
$45
Updated
2021/12/16
Biosynth Carbosynth
Product number
FB147658
Product name
1-Bromobenzocyclobutene
Packaging
500mg
Price
$110
Updated
2021/12/16
Biosynth Carbosynth
Product number
FB147658
Product name
1-Bromobenzocyclobutene
Packaging
250mg
Price
$65
Updated
2021/12/16
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1-Bromobenzocyclobutene Chemical Properties,Usage,Production

Chemical Properties

Colorless to pale yellow liquid

Uses

1-Bromobenzocyclobutene may be used in the synthesis of following compounds:

  • five-membered zirconacycles
  • benzocyclobutenol and benzocyclobutenone
  • 2,3-dimethoxyprotoberberinium bromide, via reaction with 3,4-dihydro-6,7-dimethoxyisoquinoline

General Description

1-Bromobenzocyclobutene is a useful synthon. It has important applications in organometallic methodology. Reaction between cycloheptatriene, bromoform, potassium carbonate and 18-crown-6 at 140°C yields 1-bromobenzocyclobutene.

Synthesis

75-25-2

544-25-2

21120-91-2

In a 250 mL round bottom flask equipped with a drying tube and condenser, cycloheptatriene (30.7 g, 300 mmol), tribromomethane (25.3 g, 100 mmol), anhydrous K2CO3 (15.0 g, 109 mmol), and 18-crown-6 (0.75 g) were added. The mixture was heated with stirring at 145°C for 9-10 hours. After completion of the reaction, the solution was allowed to cool to room temperature and diluted with an equal volume of acetone. Silica gel (15.0 g) was added to the reaction mixture and the insoluble solid residue was separated by vacuum filtration and the filter cake was washed with acetone until the washings were colorless. The filtrate was concentrated and the residual cycloheptatriene was removed by distillation. The viscous brown residue was dissolved in hot petroleum ether and the filtrate was concentrated after removing the precipitate by filtration. Vacuum distillation through a Vigreaux column gave slightly impure 1-bromobenzocyclobutene. Further purification by redistillation gave pure 1-bromobenzocyclobutene (2.95 g, 5.94% yield) as a light yellow liquid.1H NMR (300 MHz, CDCl3) δ 7.28 (m, 1H, ArH), 7.16 (d, 1H, J = 7.0 Hz, ArH), 7.07 (d, 1H, J = 6.4 Hz, ArH), 7.07 (d, 1H, J = 6.4 Hz, ArH) 5.39 (m, 1H, CH), 3.85 (dd, 1H, J = 4.4 Hz, J = 14.7 Hz, CH2), 3.45 (d, 1H, J = 14.7 Hz, CH2).

References

[1] Patent: WO2008/24435, 2008, A2. Location in patent: Page/Page column 104

1-Bromobenzocyclobutene Preparation Products And Raw materials

Raw materials

Preparation Products

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1-Bromobenzocyclobutene Suppliers

PharmaBlock Sciences (Nanjing),Inc.
Tel
025-86918202 4000255188
Fax
86-025-86918232
Email
sales@pharmablock.com
Country
China
ProdList
5000
Advantage
55
Energy Chemical
Tel
021-021-58432009 400-005-6266
Fax
021-58436166
Email
sales8178@energy-chemical.com
Country
China
ProdList
44801
Advantage
61
Shanghai Longsheng chemical Co.,Ltd.
Tel
021-58099652-8005 13585536065
Fax
021-58099609
Email
bin.wu@shlschem.com
Country
China
ProdList
9883
Advantage
59
Shanghai Hanhong Scientific Co.,Ltd.
Tel
021-54306202 13764082696
Email
info@hanhongsci.com
Country
China
ProdList
42934
Advantage
64
China DongFan Chemical Co.,LTD
Tel
86-0571-85151182
Fax
86-0571-85151182
Country
China
ProdList
5691
Advantage
66
Shanghai MOF Chemical Tech Limited
Tel
13661494087 18964793018
Fax
86-021-51821718 QQ:2427604606
Email
sales@mof-chemicals.com
Country
China
ProdList
293
Advantage
55
Beijing Universal Century Technology Co., Ltd.
Tel
400-8706899
Fax
400-8706899
Email
hysj_bj.com
Country
China
ProdList
3583
Advantage
55
Beijin Yangguang Furui Chemical co.,Ltd.
Tel
010-57495520 13521095525
Email
zhw512@foxmail.com
Country
China
ProdList
488
Advantage
55
Bide Pharmatech Ltd.
Tel
400-164-7117 13681763483
Fax
+86-21-61629029
Email
product02@bidepharm.com
Country
China
ProdList
39966
Advantage
60
Mianyang Chemget Chemical Co., Ltd.
Tel
816-816-2551723 18681628050
Fax
08162551905
Email
sales@chemget.com.cn
Country
China
ProdList
101
Advantage
58
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View Lastest Price from 1-Bromobenzocyclobutene manufacturers

Benzolyte BCB Technology Co., Ltd
Product
1-Bromobenzocyclobutene 21120-91-2
Price
US $0.00/KG
Min. Order
1KG
Purity
97%
Supply Ability
100KG
Release date
2025-08-20
ZHENGZHOU JIUYI TIME NEW MATERIALS CO,.LTD
Product
1-Bromobenzocyclobutene 21120-91-2
Price
US $3.00-9.00/KG
Min. Order
0.1KG
Purity
99%
Supply Ability
g-kg-tons, free sample is available
Release date
2025-07-03
Henan Fengda Chemical Co., Ltd
Product
1-Bromobenzocyclobutene 21120-91-2
Price
US $101.00-1.00/KG
Min. Order
1KG
Purity
99%
Supply Ability
g-kg-tons, free sample is available
Release date
2023-12-28

21120-91-2, 1-BromobenzocyclobuteneRelated Search:


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