when alkenes are heated with Br2 or Cl2 at high temperature hydrogen atom of allylic carbon is sunstittuted with halogen atom given allyl halide
Answers
Mark as a Brainlist
also follow me
Alkenes react in the cold with pure liquid bromine, or with a solution of bromine in an organic solvent like tetrachloromethane. The double bond breaks, and a bromine atom becomes attached to each carbon. The bromine loses its original red-brown color to give a colorless liquid.
Description: Treatment of alkenes with bromine (Br2) gives vicinal dibromides (1,2-dibromides). Notes: The bromines add to opposite faces of the double bond (“anti addition”). Sometimes the solvent is mentioned in this reaction – a common solvent is carbon tetrachloride (CCl4).
N-bromosuccinimide
NBS (N-bromosuccinimide) is the most commonly used reagent to produce low concentrations of bromine. When suspended in tetrachloride (CCl4), NBS reacts with trace amounts of HBr to produce a low enough concentration of bromine to facilitate the allylic bromination reaction.
A chain reaction mechanism for the chlorination of methane has been described. Bromination of alkanes occurs by a similar mechanism, but is slower and more selective because a bromine atom is a less reactive hydrogen abstraction agent than a chlorine atom, as reflected by the higher bond energy of H-Cl than H-Br.
Problem 11.39: Br2 is much more soluble in tetrachloromethane, CCl4 [aka "carbon tetrachloride"], than in water. ... Water, on the other hand is quite polar and has strong hydrogen bonds. Neither of these is conducive to dissolving bromine!
Bromination: Any reaction or process in which bromine (and no other elements) are introduced into a molecule. Bromination of an alkene by electrophilic addition of Br2. Bromination of a benzene ring by electrophilic aromatic substitution. Bromination of a benzylic position by a free radical substitution reaction.
Bromine water is an orange solution of bromine. It becomes colourless when it is shaken with an alkene. Alkenes can decolourise bromine water, but alkanes cannot. ... This has the effect of 'saturating' the molecule, and will turn an alkene into an alkane.
and many more....