clear slightly yellow to yellow liquid
4-Bromostyrene is widely utilized in the synthesis of nitroolefins by alkene cross-metathesis. It plays an important role in the Heck reaction to the synthesis of poly(1,4-phenylenevinylene). It is employed in the structure activity relationships (SAR) study of the chemical and biochemical properties of the vinyl group of styrene. It is also used to investigate the photochemical growth of Br-terminated self-assembled monolayers. It is also involved in the synthesis of silsesquioxanes.
4-Bromostyrene is a para-halogenated styrene derivative. The proton spectra of 4-bromostyrene exhibits dipolar couplings consistent with planar ground state structures, only if the torsional motion of lowest frequency occurs at about 80cm-1. It undergoes Heck reaction with 2-bromo-6-methoxynaphthalene in the presence of sodium acetate and Hermann′s catalyst in N,N-dimethylacetamide to afford diarylethene.
It polymerises above 75o in the presence of benzoyl peroxide. To purify, if it has not gone to a solid resin, dissolve it in Et2O, dry (MgSO4) and add ca 0.1g of 4-tertbutylcatechol (polymerisation inhibitor) per 100g of bromostyrene. Filter, evaporate this under reduced pressure (use as high a vacuum as possible) and distil the residue. Store it in dark bottles in the presence of the inhibitor (at above concentration). [Overberger & Saunders Org Synth Coll Vol III 204 1955, Beilstein 5 IV 1349.]
