2R3Rdibromobutane

2,3-Dibromobutane is an organic chemical compound with the molecular formula C4H8Br2. It is a dibromoalkane, meaning it is a butane molecule where two hydrogen atoms have been replaced by bromine atoms. Specifically, the bromine atoms are located on the second and third carbon atoms of the butane chain. There are stereoisomers of 2,3-dibromobutane due to the chiral centers at the second and third carbon atoms. These include (2R,3R)-2,3-dibromobutane, (2S,3S)-2,3-dibromobutane, and the meso compound (2R,3S)-2,3-dibromobutane, which is identical to (2S,3R)-2,3-dibromobutane due to internal symmetry.

The synthesis of 2,3-dibromobutane typically involves the bromination of but-2-ene. This reaction proceeds via an electrophilic addition mechanism, where bromine adds across the double bond. The stereochemical outcome of this addition depends on the reagent and reaction conditions. For example, addition of bromine to *trans*-but-2-ene yields a racemic mixture of (2R,3R)- and (2S,3S)-2,3-dibromobutane, while addition to *cis*-but-2-ene yields the meso compound.

2,3-Dibromobutane is a colorless liquid. It can undergo dehydrobromination reactions to form unsaturated hydrocarbons such as butenes and alkynes, or it can be used in nucleophilic substitution reactions. Its properties and reactivity are characteristic of vicinal dibromides.