Boron tribromide

Boron tribromide (BBr₃) is a strong Lewis acid generally used as a reagent for the deprotection of ethers. Alkyl aryl ethers are cleaved at the alkyl-oxygen bond to give ArOH and alkyl bromides. In a particular case, BBr₃ was used to cleave acetals that could not be deprotected under standard acidic conditions. Similarly, amino acid-protecting groups such as benzyloxycarbonyl and tert-butoxycarbonyl groups can be deprotected by BBr₃. It can also be used to deprotect carbohydrate derivatives and polyoxygenated intermediates in the preparation of deoxyvernolepin, vernolepin, and vernomenin.

With alkynes forms 2-alkenyldibromoboranes, which show reversed regiochemistry in Diels-Alder reactions as compared to BBN. Intermediates generated from 1-alkynes couple to alkyl halides providing trisubstituted alkenes. Reacts with chiral sulfonamides to provide precursors of chiral glycidol esters, acetate diols, β-hydroxy esters, and amino acid esters. Useful for the synthesis of precursors to group 13-15 semiconductor materials.

Reactant for preparation of:

• Drug intermediate 6-nitro-L-DOPA
• Luminescent polystyrene derivatives with sterically protected carbazolylborane moieties
• High-quality boron-doped graphene via Wurtz-type reductive coupling reaction
• Mercapto-(+)-methamphetamine haptens for synthesis of (+)-methamphetamine conjugate vaccines with improved epitope densities
• Micrometer-sized organic molecule-DNA hybrid structures
• Borane complexes via electrophilic aromatic borylation reactions
• A 5-HT2C receptor agonist
• Biphenyl-derivatives possessing tertiary amino groups as β-secretase(BACE1) inhibitors for the treatment of Alzheimer′s disease
• A highly near-IR region fluorescent p-extended boron aza-dipyrromethene moiety unit
• Tetrahydroisoquinoline derivatives via intramolecular cyclization of methoxy-substituted N-phenethylimides