(E)-1,4-Dibromobut-2-ene 2-BUTENE, 1,4-DIBROMO-, trans- 2-Butene, 1,4-dibromo-, (2E)- 4-01-00-00791 (Beilstein Handbook Reference) 821-06-7 BRN 1719696 Dibromobutene EINECS 212-472-7 trans-1,4-Dibromobut-2-ene