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Updated: Jun 1, 2026
08:12
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
(4-Bromo-phen-yl)(1H-indol-7-yl)methanone
Summary
Structural analysis of C(15)H(10)BrNO reveals molecules forming centrosymmetric dimers via N-H⋯O hydrogen bonds. The study details specific dihedral angles between the indole and benzene rings, offering insights into molecular conformation.
Area of Science:
- Crystallography and Molecular Structure
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Understanding the solid-state packing and intermolecular interactions of organic molecules is crucial for predicting material properties.
- The title compound, C(15)H(10)BrNO, is a novel organic molecule whose crystal structure has not been previously reported.
- Hydrogen bonding plays a significant role in the self-assembly of molecules in the crystalline state.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(15)H(10)BrNO.
- To investigate the intermolecular interactions, specifically hydrogen bonding, present in the crystal lattice.
- To analyze the conformational preferences of the molecule, including dihedral angles between its ring systems and the central bridge.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional structure of the compound.
- Analysis of the crystal structure involved identifying hydrogen bond donors and acceptors to characterize intermolecular interactions.
- Geometric parameters, including bond angles and dihedral angles, were precisely measured and analyzed.
Main Results:
- The crystal structure reveals that C(15)H(10)BrNO molecules form centrosymmetric dimers mediated by pairs of N-H⋯O hydrogen bonds.
- A significant dihedral angle of 50.13(5)° was observed between the indole and benzene ring planes.
- The indole ring is less twisted (15.51(3)°) compared to the benzene ring (40.13(7)°) relative to the central C-C(=O)-C bridge, indicating distinct conformational preferences.
Conclusions:
- The N-H⋯O hydrogen bonds are the primary driving force for the formation of dimeric supramolecular structures in the crystal.
- The observed dihedral angles provide quantitative data on the molecular conformation and the influence of substituents on planarity.
- The bond angles within the benzene ring suggest an approximately additive effect of the substituents, offering insights into electronic and steric influences.
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