(5Z,7Z,9Z)-5,10-Dibromobenzo[8]annulene

Abstract

In the structure of the title compound, C12H8Br2, the two bromine substituents are oriented exo to the boat-shaped cyclo­octa­tetra­ene at the two ring sites that are β to the ring fusion positions. The average Br—C bond distance is 1.919 (2) Å, the average distance for C=C double bonds that are Br substituted is 1.328 (2) Å, while the other two double-bond distances are 1.327 (2) and 1.398 (2) Å for the non-fused and fused bonds, respectively. Each type of ring inter­atomic distance is within s.u. of the average values for the four known structures, including the title compound, of benzo-fused cyclo­ocata­tetra­enes that are not coordinated to a metal atom. The crystal structure features short Br⋯Br [3.6620 (3) Å] and C⋯H [2.834 (2) and 2.841 (2) Å] contacts.

Accurate Crystal Structures of C12H9CN, C12H8(CN)2, and C16H11CN Valence Isomers Using Nonspherical Atomic Scattering Factors

“…Values from structures introduced in this paper are included in this average unless otherwise specified. Comparators used in this category: BUYYUP, CUDYUV, FIVHIB, LEZMAE, LIPVAJ, QOGYER, QOGZAO, OWUVUA, OWUWAH, OWUWEL d Statistical outlier omitted from the averaged values. …”