1,4-Bis(hex-yloxy)-2,5-diiodo-benzene
Summary
This study details the crystal structure of a centrosymmetric diiodo compound, revealing distinct alkyl chain orientations and intermolecular interactions compared to its bromo analogue. The findings highlight C-H⋯π contacts forming a 2D network in the diiodo structure.
Area of Science:
- Crystallography
- Organic Chemistry
- Materials Science
Background:
- Centrosymmetric compounds exhibit unique structural properties.
- Alkyl chain conformation and orientation significantly influence crystal packing.
- Halogen bonding and C-H⋯π interactions are key intermolecular forces in crystal engineering.
Purpose of the Study:
- To elucidate the crystal structure of the title diiodo compound C(18)H(28)I(2)O(2).
- To compare its structural features, particularly alkyl chain conformation and intermolecular interactions, with a known centrosymmetric bromo analogue.
- To understand the role of halogen substituents on crystal packing and network formation.
Main Methods:
- Single-crystal X-ray diffraction analysis was performed on the title compound.
- The crystal structure was solved and refined using standard crystallographic techniques.
- Comparison of structural parameters, including torsion angles and dihedral angles, was made with the bromo analogue.
Main Results:
- The title compound, C(18)H(28)I(2)O(2), crystallized in the monoclinic space group P2(1)/c.
- Alkyl chains adopted extended all-trans conformations, with a notable torsion angle of 55.8(5)° around the O-C(alkyl) bond.
- Unlike the bromo analogue, the diiodo compound lacks halide⋯halide interactions, instead forming a 2D network via C-H⋯π contacts.
Conclusions:
- The diiodo compound exhibits a different crystal packing arrangement compared to its bromo analogue, primarily due to variations in alkyl chain orientation.
- The absence of halide⋯halide interactions and the presence of C-H⋯π contacts in the diiodo structure demonstrate the influence of the halogen substituent on intermolecular forces.
- These findings contribute to the understanding of structure-property relationships in centrosymmetric organic compounds and inform crystal engineering strategies.
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