text: Hydrogen bromide and hydrobromic acid are important reagents in the production of organobromine compounds.  In an electrophilic addition reaction, HBr adds to alkenes:
  The resulting alkyl bromides are useful alkylating agents, e.g., as precursors to fatty amine derivatives.  Related free radical additions to allyl chloride and styrene give 1-bromo-3-chloropropane and phenylethylbromide, respectively.
  Hydrogen bromide reacts with dichloromethane to give bromochloromethane and dibromomethane, sequentially:
  These metathesis reactions illustrate the consumption of the stronger acid (HBr) and release of the weaker acid (HCl).
  Allyl bromide is prepared by treating allyl alcohol with HBr:
  HBr adds to alkynes to yield bromoalkenes.  The stereochemistry of this type of addition is usually anti:
  : RC≡CH + HBr → RC(Br)=CH
  Also, HBr adds epoxides and lactones, resulting in ring-opening.
  With triphenylphosphine, HBr gives triphenylphosphonium bromide, a solid "source" of HBr.