Trans-1,2-dibromocyclohexane

Definition

trans-1,2-dibromocyclohexane is a cyclic organic compound with two bromine atoms attached to adjacent carbon atoms in a trans configuration on a cyclohexane ring. It is a key intermediate in the halogenation of alkenes through the addition of X2 (where X = halogen).

5 Must Know Facts For Your Next Test

1. The addition of bromine (Br2) to an alkene results in the formation of a trans-1,2-dibromocyclohexane intermediate.
2. The bromine atoms in trans-1,2-dibromocyclohexane are positioned on opposite sides of the cyclohexane ring, maximizing the distance between them.
3. The trans configuration is the thermodynamically favored product in the halogenation of alkenes due to steric and electronic factors.
4. trans-1,2-Dibromocyclohexane is an important intermediate in the synthesis of various organic compounds, such as alcohols and other halogenated derivatives.
5. The stereochemistry of the final product in the halogenation of alkenes can be controlled by the choice of reaction conditions, such as the solvent, temperature, and the presence of catalysts.

Review Questions

• Explain the formation of trans-1,2-dibromocyclohexane during the halogenation of alkenes.
  • The halogenation of alkenes, such as the addition of bromine (Br2), proceeds through the formation of a cyclic bromonium ion intermediate. This intermediate then undergoes nucleophilic attack by a bromide ion, resulting in the formation of trans-1,2-dibromocyclohexane. The trans configuration is the thermodynamically favored product due to the minimization of steric interactions between the bromine atoms, which are positioned on opposite sides of the cyclohexane ring.
• Describe the role of trans-1,2-dibromocyclohexane in the synthesis of other organic compounds.
  • trans-1,2-Dibromocyclohexane is an important intermediate in the synthesis of various organic compounds. It can be converted to other halogenated derivatives, such as alcohols, through nucleophilic substitution reactions. Additionally, the stereochemistry of the final product can be controlled by the choice of reaction conditions, allowing for the selective synthesis of desired stereoisomers. This versatility makes trans-1,2-dibromocyclohexane a valuable building block in organic chemistry.
• Analyze the factors that contribute to the formation of the trans configuration in the halogenation of alkenes.
  • The formation of the trans configuration in the halogenation of alkenes is influenced by several factors. Firstly, the trans configuration is the thermodynamically favored product due to the minimization of steric interactions between the bulky halogen atoms. Electronically, the trans arrangement maximizes the distance between the electronegative halogen atoms, reducing repulsive interactions. Additionally, the reaction conditions, such as the choice of solvent, temperature, and the presence of catalysts, can further influence the stereochemical outcome of the halogenation reaction by affecting the stability and reactivity of the intermediates involved.

Related terms

Halogenation:

The process of adding a halogen (such as chlorine, bromine, or iodine) to an organic compound.

Cyclohexane:

A saturated cyclic hydrocarbon with the chemical formula C6H12.

Trans configuration: The spatial arrangement of atoms or groups in a molecule where the substituents are on opposite sides of a ring or double bond.