Related Experiment Videos
Di- and trinitrophenanthrenes: synthesis, separation, and reduction property
K Fukuhara1, M Takei, H Kageyama
1National Institute of Health Sciences, Tokyo, Japan.
Chemical Research in Toxicology
|January 1, 1995
Summary
This study developed methods to synthesize and isolate eleven dinitrophenanthrenes (DNPHs) and nine trinitrophenanthrenes (TNPHs) from phenanthrene nitration. These compounds
Area of Science:
- Environmental Chemistry
- Organic Chemistry
- Analytical Chemistry
Background:
- Nitrated polycyclic aromatic hydrocarbons (nitrated PAHs), particularly dinitrated PAHs, are recognized as potent environmental pollutants with mutagenic and carcinogenic properties.
- The synthesis and characterization of di- and trinitrophenanthrenes (DNPHs and TNPHs) have been limited, hindering a full understanding of their environmental impact.
Purpose of the Study:
- To establish efficient methods for the direct nitration of phenanthrene to produce DNPHs and TNPHs.
- To isolate and structurally elucidate various DNPH and TNPH isomers.
- To investigate the reduction properties and electronic characteristics of the synthesized nitrophenanthrenes.
Main Methods:
- Direct nitration of phenanthrene using fuming nitric acid in acetic anhydride and without solvent.
- Isolation of eleven DNPH isomers and nine TNPH isomers using preparative High-Performance Liquid Chromatography (HPLC).
- Structural determination using 1H Nuclear Magnetic Resonance (NMR) and electron impact mass spectrometry (EI-MS).
- Examination of reduction properties via cyclic voltammetry and calculation of Lowest Unoccupied Molecular Orbital (LUMO) energy levels using the AM1 method.
Main Results:
- Eleven DNPHs were isolated with a total yield of 62.6%, including 2,10-DNPH (14.2%) and 1,10-DNPH (8.0%) as major products.
- Nine TNPHs were obtained with a total yield of 46.5%, with 3,6,9-TNPH (9.2%) and 2,6,9-TNPH (9.0%) being the most abundant.
- A correlation was found between the calculated LUMO energy levels and the measured first reduction potentials (E1/2).
- The study discussed the conformations of nitro substituents relative to the phenanthrene ring system.
Conclusions:
- The study successfully developed and optimized methods for synthesizing a diverse range of DNPHs and TNPHs.
- The comprehensive isolation and characterization provide valuable data for understanding the environmental behavior and potential toxicity of these compounds.
- The correlation between electronic properties and reduction potentials offers insights into the reactivity of nitrophenanthrenes.