Related Experiment Video
Updated: Sep 28, 2025
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Crystal structures of 3-halo-2-organochalcogenylbenzo[b]chalcogenophenes
Eduardo Q Luz1, Francielli S Santana2, Gabriel L Silverio1
1Laboratory of Polymers and Catalysis (LaPoCa), Department of Chemistry, Federal University of Paraná-UFPR, PO Box 19061, Curitiba, PR, 81531-980, Brazil.
Abstract:
The structure of the title compounds 3-bromo-2-(phenyl-sulfan-yl)benzo[b]thiophene (C14H9BrS2; 1), 3-iodo-2-(phenyl-sulfan-yl)benzo[b]thio-phene (C14H9IS2; 2), 3-bromo-2-(phenyl-selan-yl)benzo[b]seleno-phene (C14H9BrSe2; 3), and 3-iodo-2-(phenyl-selan-yl)benzo[b]seleno-phene (C14H9ISe2; 4) were determined by single-crystal X-ray diffraction; all structures presented monoclinic (P21/c) symmetry. The phenyl group is distant from the halogen atom to minimize the steric hindrance repulsion for all structures. Moreover, the structures of 3 and 4 show an almost linear alignment of halogen-selenium-carbon atoms arising from the intra-molecular orbital inter-action between a lone pair of electrons on the halogen atom and the anti-bonding σ*Se-C orbital (n halogen→σ*Se-C). This inter-action leads to significant differences in the three-dimensional packing of the mol-ecules, which are assembled through π-π and C-H⋯π inter-actions. These data provide a better comprehension of the inter-molecular packing in benzo[b]chalcogenophenes, which is relevant for optoelectronic applications.
More Related Videos
Related Concept Videos
01:18Structure of Benzene: Molecular Orbital Model
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
02:42Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:38Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
01:07Radicals: Electronic Structure and Geometry
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...