Synthesis, Crystallographic Characterization and Density Functional Study of Novel Spoke-Molecular Tetravent ethyltriphenylphosphorous Dibromide

Chem Sci Trans., 2016, 5(3), pp 674-686

DOI:10.7598/cst2016.1256

Research Article

Synthesis, Crystallographic Characterization and Density Functional Study of Novel Spoke-Molecular Tetravent ethyltriphenylphosphorous Dibromide

A. M. MKADMH*, A. M. ABU-SHANAB, R.Y. MORJAN, Z. SAFI, ROBIN G. PRITCHARD and JOHN M. GARDINER

Chemistry Department, College of Applied Science, Al-Aqsa University, Gaza- Palestine
Chemistry Department, College of Science, Islamic University of Gaza, Gaza-Palestine
Chemistry Department, College of Applied Science, Al-Azhar University, Gaza- Palestine
School of Chemistry, The University of Manchester, Manchester, M13 9PL, UK
Manchester Institute of Biotechnology, School of Chemistry, Faculty of EPS, The University of Manchester, Manchester M1 7DN, UK

Abstract

A novel molecular tetravalent ethyltriphenylphosphorous dibromide ((C₆H₅)₃PCH₂Br₂ ) has been synthesized in toluene and has been characterized by single crystal x-ray crystallography. Theoretical studies have been conducted utilizing DFT(B3LYP/6-311+G(d,p) level of theory both in gas phase and solution using diverse solvents. Potential surface energy calculations revealed the existence of the tetravalent diionic form as a global minimum except in dimethylsulfoxide where our adduct is more stable. Calculations showed that the Br-Br bond distance is in quadratic variation with the medium dielectric constant. The unusual Br-Br lengthen is reasonably rationalized in terms of charge transfer of electron density from the  clouds in phenyl moieties to the σ* of the dibromine entity. The average harmonic oscillator index of aromaticity of the complex are found suffering a deviation from unity.