4-Bromobenzocyclobutene (CAS NO.1073-39-8) is also named as 3-Bromobicyclo[4.2.0]octa-1,3,5-triene ; Bicyclo[4.2.0]octa-1,3,5-triene, 3-bromo- ; 4-Bromo-1,2-dihydrobenzocyclobutene .