Structural formula
Business number | 03RM |
---|---|
Molecular formula | C5H9Br |
Molecular weight | 149.04 |
label |
Bromocyclopentane; cyclopentyl bromide, Cyclopentyl bromide, Alicyclic compounds |
Numbering system
CAS number:137-43-9
MDL number:MFCD00001359
EINECS number:205-294-6
RTECS number:None
BRN number:1209256
PubChem number:24892365
Physical property data
1. Properties: colorless liquid. Has a sweet aromatic smell. Sensitive to light.
2. Density (g/mL, 25/4℃): 1.3866
3. Relative vapor density (g/mL, air=1): Undetermined
4. Melting point (ºC): Undetermined
5. Boiling point (ºC, normal pressure): 137~139
6. Boiling point (ºC, 5.2kPa): Undetermined Determine
7. Refractive index: 1.4885
8. Flash point (ºC): 42℃ (closed cup)
9. Specific rotation (º) : Undetermined
10. Autoignition point or ignition temperature (ºC): Undetermined
11. Vapor pressure (kPa, 25ºC): Undetermined
12. Saturated vapor pressure (kPa, 60ºC): Undetermined
13. Heat of combustion (KJ/mol): Undetermined
14. Critical temperature (ºC): Undetermined
15. Critical pressure (KPa): Undetermined
16. Log value of oil-water (octanol/water) partition coefficient: Undetermined
17. Explosion Upper limit (%, V/V): Undetermined
18. Lower explosion limit (%, V/V): Undetermined
19. Solubility: Soluble in ethanol and ether, Insoluble in water. It turns brown after being left for a long time.
Toxicological data
None
Ecological data
None
Molecular structure data
1. Molar refractive index: 30.84
2. Molar volume (cm3/mol): 103.0
3. Isotonic specific volume (90.2K ): 251.4
4. Surface tension (3.0 dyne/cm): 35.4
5. Polarizability (0.5 10-24cm 3): 12.22
Compute chemical data
1. Reference value for hydrophobic parameter calculation (XlogP): 2.3
2. Number of hydrogen bond donors: 0
3. Number of hydrogen bond acceptors: 0
4. Number of rotatable chemical bonds: 0
5. Number of tautomers: none
6. Topological molecule polar surface area 0
7. Number of heavy atoms: 6
8. Surface charge: 0
9. Complexity: 37.2
10. Number of isotope atoms: 0
11. Determine the atomsNumber of stereocenters: 0
12. Number of uncertain atom stereocenters: 0
13. Determined number of stereocenters of chemical bonds: 0
14 .The number of uncertain chemical bond stereocenters: 0
15. The number of covalent bond units: 1
Properties and stability
When the concentration is high, it damages the liver and has an anesthetic effect. See 1-bromoisopentane (A057). The production site must have good ventilation and the equipment must be sealed. Operators wear protective equipment.
Storage method
This product should be sealed and stored in a cool, dark place.
This product is packaged in iron drums or iron drums lined with plastic drums. Store in a cool, ventilated place. Protect from sun, heat and keep away from fire sources. Store and transport according to general chemical regulations.
Synthesis method
Obtained by bromination of cyclopentanol:
Mix cyclopentanol and hydrobromic acid, heat to about 170°C and reflux for 6~8 hours, then Distill with water vapor, wash the oil layer with 5% sodium carbonate, then dry, filter and fractionate, and collect the 136~139°C fraction as the finished product. Another method involves the reaction of cyclic alcohols with phosphorus tribromide. Cool the cyclopentanol to 0°C, add freshly steamed phosphorus tribromide dropwise, complete the addition at 0~5°C, stir for 2 hours, and leave it at room temperature overnight. After adding water, separate the layers and take the oil layer for steam distillation. The distillate is separated into layers, and the oil layer is washed with 10% carbonsodium hydrogen acid solution, dried with anhydrous calcium chloride, filtered, the filtrate is distilled, and the 134~141°C fraction is collected. Obtain bromocyclopentane.
Purpose
Used in organic synthesis. Used as an intermediate for the synthesis of pharmaceuticals (cyclopentamethizine) and other organic substances.