Steric hindrance and the conformation of molecules

Autor: Yu. T. Struchkov, T. L. Khotsyanova
Rok vydání: 1960
Předmět:
Zdroj: Bulletin of the Academy of Sciences of the USSR Division of Chemical Science. 9:1275-1283
ISSN: 1573-9171
0568-5230
Popis: 1. The crystal structure of 2,6-dichloro-4-nitrodimethylaniline was determined; the interatomic distances and valence angles were found with accuracies of ±0.01 A and ±2°, respectively. 2. Steric hindrance at CH3... Cl leads to rotation of the dimethylamino group by 60.5° relative to the benzene nucleus and deformation of the C-C-Cl valence angles by 4°. 3. The loss in coplanarity disrupts conjugation in the molecule, which is reflected in the lengths of the carbon-nitrogen bonds: C-NO2=1,43 A; C-N(CH3)2=1,41 A; N-CH3=1,46 A. 4. The actual conformation of the molecule is established as a result of a compromise between the tendencies to coplanarity, retention of normal valence angles, and minimum steric hindrance. 5. The structure is characterized by a high coordination number and density. Most intermolecular contacts occur at normal distances.
Databáze: OpenAIRE