Langbahn Team – Weltmeisterschaft

Bromotoluene

Bromotoluenes are aryl bromides based on toluene in which at least one aromatic hydrogen atom is replaced with a bromine atom. They have the general formula C7H8–nBrn, where n = 1–5 is the number of bromine atoms.

Monobromotoluene

Monobromotoluenes are bromotoluenes containing one bromine atom. There are three isomers, each with the formula C7H7Br.

Properties

The isomers differ in the location of the bromine, but have the same chemical formula.

Monobromotoluene isomers[1][2][3]
Common name o-bromotoluene m-bromotoluene p-bromotoluene
Structure
Systematic name 1-bromo-2-methylbenzene 1-bromo-3-methylbenzene 1-bromo-4-methylbenzene
Molecular formula C7H7Br (C6H4BrCH3)
Molar mass 171.03 g/mol
Appearance colorless liquid colorless liquid white crystalline solid
CAS number [95-46-5] [591-17-3] [106-38-7]
Properties
Density and phase 1.431 g/ml, liquid 1.4099 g/ml, liquid 1.3995 g/ml, solid
Solubility in water practically insoluble
Other solubilities very soluble in ethanol, ether, benzene, carbon tetrachloride, acetone, chloroform
Melting point -27.8 °C (-18.0 °F; -409.63 K) -39.8 °C (-39.6 °F; -388.03 K) 28.5 °C (83.3 °F; 301.7 K)
Boiling point 181.7 °C (359.1 °F; 454.9 K) 183.7 °C (362.7 °F; 456.9 K) 184.5 °C (364.1 °F; 457.7 K)

Benzyl bromide is an isomer, which has a bromine substituted for one of the hydrogens of toluene's methyl group, and it is sometimes named α-bromotoluene.

Preparation

A laboratory route to p-bromotoluene proceeds from p-toluidine, which is diazotiized followed by treatment with copper(I) bromide.[4]

Uses

Bromotoluenes are precursors to many organic building blocks. For example, the methyl group may be oxidized using potassium permanganate to form the corresponding bromobenzoic acid.[5] The methyl group may also be partially oxidized to form bromobenzaldehyde.[6]

See also

References

  1. ^ "2-Bromotoluene". PubChem. National Center for Biotechnology Information. Retrieved January 19, 2023.
  2. ^ "3-Bromotoluene". PubChem. National Center for Biotechnology Information. Retrieved January 19, 2023.
  3. ^ "4-Bromotoluene". PubChem. National Center for Biotechnology Information. Retrieved January 19, 2023.
  4. ^ Bigelow, L. A. (1925). "p-BROMOTOLUENE". Organic Syntheses. 5: 21. doi:10.15227/orgsyn.005.0021.
  5. ^ Bigelow, L. A. (1922). "A Study of Side-Chain Oxidations with Potassium Permanganate. Ii". Journal of the American Chemical Society. 44 (9): 2010–2019. doi:10.1021/ja01430a020.
  6. ^ Coleman, G. H.; Honeywell, G. E. (1937). "p-BROMOBENZALDEHYDE". Organic Syntheses. 17: 20. doi:10.15227/orgsyn.017.0020.