4-bromophenyl isocyanate

4-Bromophenyl isocyanate (CAS 2493-02-9), also known as p-bromophenyl isocyanate, is a reactive aryl isocyanate used as a building block in organic synthesis and polymer chemistry. The bromine substituent provides a handle for further functionalization, making it a practical intermediate for constructing complex molecular architectures in pharmaceutical and specialty chemical workflows.

In pharmaceutical synthesis, it serves as a key intermediate for preparing urea-containing drug candidates and bioactive compounds where the bromine atom enables downstream cross-coupling reactions. Agrochemical and fine chemical manufacturers use it to introduce the bromophenyl-urea motif into active ingredient scaffolds. In polymer research, it functions as a monomer for producing specialty polyureas.

Biotechnology researchers also employ it in the preparation of labeled probes and derivatization reagents for analytical applications. It is supplied as a liquid or low-melting solid in high-purity grades. Standard offerings include reagent-grade and synthesis-grade material, with purity specifications commonly at 97% or higher by GC. Packaging ranges from small quantities to bulk quantities for industrial use.