Computational Chemistry Methods

Applications

Ponnadurai Ramasami, Ponnadurai Ramasami

• Publisher: De Gruyter
• Year: 2020
• ISBN:
  9783110629927
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Chemistry
• Index: Chemistry

This book reviews a variety of methods in computational chemistry and their applications in different fields of current research. Ab initio methods and regression analyses are discussed with special focus on their application to investigate chemical structures as for example dyes or drug compounds. Further topics are the use of computational methods in the modeling of spectroscopic data or to study reaction mechanisms.

1 Investigation of the aromat zaphenanthrene derivatives

Erhan Öztürk

Faculty of Science, Department of Chemistry, Van Yuzuncu Yil University, Van, Turkey

Science Application and Research Center, Igdir University, Igdir, Turkey

Zeynep Turhan İrak

Faculty of Engineering, Department of Environmental Engineering, Igdir University, Igdır Unv. Sehıt Bulent Yurtseven Campus, Suveren, Merkez, Igdir, Turkey

Necdet Karakoyun

Faculty of Science, Department of Chemistry, Van Yuzuncu Yil University, Van, Turkey

ORCID:https://orcid.org/0000-0002-6083-6921

Ayşegül Gümüş

Faculty of Science, Department of Chemistry, Van Yuzuncu Yil University, Van, Turkey

ORCID:https://orcid.org/0000-0002-1613-7074

Selçuk Gümüş

Faculty of Science, Department of Chemistry, Van Yuzuncu Yil University, Van, Turkey

ORCID:https://orcid.org/0000-0002-8628-8943

Abstract

In this chapter mono, di, tri and tetraaza substituted phenanthrene derivatives have been investigated computationally with B3LYP/6-31 + G(d,p) level of theory. Substitution of carbon atom of the main structure with nitrogen obviously disturbs the aromaticity, indeed it decreases it. Thus, the idea of regaining of the aromaticity back by using electron withdrawing groups came across. As a result of the computational calculations, energetically most unfavored structures have been found to be those where aza substitutiona are vicinal. Secondly, the aromaticities of the present species depend on the position of the centric substituent. In addition, the effect position of the side substituent has been considered. The system becomes more aromatic (possess greater negative NICS values or smaller HOMA value) when the electron withdrawing atoms or groups are adjacent to the centrically substituted heteroatoms.

Keywords: aromaticity, NICS, HOMA, phenanthrene, azaphenanthrene,

1.1 Introduction

The polycyclic aromatic hydrocarbon formed by fusing three benzene rings is called Phenanthrene (Ph) which takes its name from two well-known chemical compounds; ‘phenyl’ and ‘anthracene’. is It has a role as an environmental contaminant and a mouse metabolite. It is an ortho-fused polycyclic arene, an ortho-fused tricyclic hydrocarbon and a member of phenanthrenes (Figure 1.1). The steroids possess phenanthrene in their framework. It is a harmfull material in its pure form, which is spread out by cigarette smoke. Its irritant and photosensitising skin to light properties are well known. Phenanthrene emerges as a white powder chemical emitting blue fluorescence. Although is insoluble in water its solubility in most organic solvents, including toluene, carbon tetrachloride, ether, chloroform, acetic acid and benzene, is quite high. Bardhan-Sengupta Phenanthrene Synthesis is the classical synthetic application to obtain Ph [1].

Figure 1.1: Structure of phenanthrene and naming of the rings.

Phenanthrene has a significant resonance stabilization due to its tricyclic aromatic structure, as shown in the following diagram (Figure 1.2). Three fused benzene ring moieties is one of the five contributing resonance structures, in two of the structures 10 π-electron annulene is fused to a benzene ring, and the remaining two geometries are 14 π-electron annulenes. All of the resonans structures are aromatic by the https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/react3.htm#rx9ac Hückel Rule. A careful inspection of each contributing structure reveals that the carbon-carbon bond of the B–Ring has 80 % double bond character (1.34 Å bond length), whereas the opposite bond across the circle has 80 % single bond character with 1.47 Å bond length. The bond lengths shown on the right hand structure reflected that the other carbon-carbon bonds vary in terms of bond order. As expected, the carbon–carbon bonds with more than 80 % double bond character, display double bond-like addition reactions, including simple catalytic hydrogenation. Indeed both radical and polar addition reactions are observed by all the aromatic fused ring compounds which less readily benzene undergoes.

Figure 1.2: Resonance structures of phenanthrene.

Kalescky et al. [2] introduced a new description for the aromaticity of polycyclic compounds including phenantherene. They compared the aromatic character of the compounds in terms of bond strengths obtained from c...

Table of contents

• Title Page
• Copyright
• Contents
• 1 Investigation of the aromat zaphenanthrene derivatives
• 2 Conformations and interactions comparison between R- and S-methadone in wild type CYP2B6, 2D6 and 3A4
• 3 Phthalocyanines core-modified by P and S and their complexes with fullerene C60: DFT study
• 4 Application of computational chemistry for adsorption studies on metal–organic frameworks used for carbon capture
• 5 Combined approach of homology modeling, molecular dynamics, and docking: computer-aided drug discovery
• 6 Computational prediction of toxicity of small organic molecules: state-of-the-art
• 7 Effect of substituent on photostability and lightfastness of azo dye and their photodegradation mechanism – Mechanistic study using density functional theory
• 8 2,4-Dimorpholino-4-yl-6-(4-nitrophenoxy)-[1,3,5]-triazine: Structural and spectroscopic study using experimental and DFT method
• 9 Spectroscopic and DFT studies of 2,4-dichloro-N-phenethylbenzenesulfonamide
• Index