Anomalous halogen bonds in the crystal structures of 1,2,3-tri­bromo-5-nitro­benzene and 1,3-di­bromo-2-iodo-5-nitro­benzene

Acta Crystallographica Section E: Crystallographic Communications

s, S.¹  Romero, J.A.¹  Bernè³  ndez, G.⁴  Aguirre Herná⁵ 

[1] Centro de Graduados e InvestigacióInstituto de Fígico de Tijuana, Apdo. Postal 1166, 22510 Tijuana, B.C., Mexico;mica, Instituto Tecnolón en Quínoma de Puebla, Av. San Claudio y 18 Sur, 72570 Puebla, Pue., Mexico;rita Universidad Autósica, Benemé

关键词: CRYSTAL STRUCTURE;    POLYHALOGENATED BENZENE;    HALOGEN BOND;    BROMINE;    IODINE;   

DOI  :  10.1107/S2056989015013377

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

The title trihalogenated nitro­benzene derivatives, C6H2Br3NO2 and C6H2Br2INO2, crystallize in triclinic and monoclinic cells, respectively, with two mol­ecules per asymmetric unit in each case. The asymmetric unit of the tri­bromo compound features a polarized Brδ+⋯Brδ- inter­molecular halogen bond. After substitution of the Br atom in the para position with respect to the nitro group, the network of X⋯X halogen contacts is reorganized. Two inter­molecular polarized halogen bonds are then observed, which present the uncommon polarization Brδ+⋯Iδ-: the more electronegative site (Br) behaves as a donor and the less electronegative site (I) as an acceptor for the charge transfer.

【 授权许可】

CC BY