Structural formula
| Business number | 06GH |
|---|---|
| Molecular formula | C7H6Br2 |
| Molecular weight | 294.94 |
| label |
p-dibromotoluene, CH3C6H3Br2 |
Numbering system
CAS number:615-59-8
MDL number:MFCD00000090
EINECS number:210-437-0
RTECS number:None
BRN number:1859123
PubChem number:24855090
Physical property data
1. Physical property data
1. Density 1.815.
2. Boiling point: 135-136℃ (35 mmHg).
3. Melting point: 5-6℃.
4. Refractive index 1.601-1.603.
Toxicological data
None yet
Ecological data
3. Ecological data:
1. Other harmful effects: This substance may be harmful to the environment, and special attention should be paid to water bodies.
Molecular structure data
5. Molecular property data:
1. Molar refractive index: 46.45
2. Molar volume (cm3/mol): 138.0
3. Isotonic specific volume (90.2K): 345.9
4. Surface tension (dyne/cm): 39.3
5. Polarizability (10-24cm3): 18.41
Compute chemical data
1. Reference value for hydrophobic parameter calculation (XlogP): None
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: 9
8. Surface charge: 0
9. Complexity: 92.9
10. Number of isotope atoms: 0
11. Determine the number of atomic stereocenters: 0
12. Uncertain number of atomic stereocenters: 0
13. Determine the number of chemical bond stereocenters: 0
14. Number of uncertain chemical bond stereocenters: 0
15. Number of covalent bond units: 1
Properties and stability
Properties and stability:
The product may not decompose under normal temperature and pressure.
Storage method
Storage:
Seal the container and store it in a sealed main container in a cool, dry place.
Synthesis method
g (2.2mol) sodium nitrite powder is added to 1.5L concentrated sulfuric acid below 40°C, and it should be completely dissolved. 122g (1mol) 2,5-diaminotoluene was dissolved in 750mL glacial acetic acid. Keep the reaction below 30°C and add it to the prepared nitrosyl sulfuric acid to ensure complete diazotization of the two amino groups; stir for another 10 minutes after the addition. Then slowly add the cuprous bromide solution below 40°C [144g (0.57mol) crystallized copper sulfate, 48g (0.75mol) copper chips, 2.4L water, 384g (2.7mol) crystalline sodium bromide, and add while stirring Reflux 72g (0.73mol) concentrated sulfuric acid together for 4 to 5 hours to obtain a light yellow solution; if it is still blue, add some sodium sulfite to make the blue color basically disappear. ] Steam distillation to obtain 108g of 2,5-dibromotoluene, with a yield of 44%. 
Purpose
Organic synthesis intermediates
