Synthesis, crystal structure and ab initio/DFT calculations of a derivative of dithiophosphonates

Abstract

The compound 2 has been synthesized from the reaction of 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide and (R)-1-[3,5-Bis(trifloromethyl)phenyl]ethanol in toluene. The obtained crude dithiophosphonic acid 1 has been treated with the excess of N(C2H5)(3) to give rise to 2, [(+HN(C2H5)(3)][(O-CH3CH-C6H3(CF3)(2))(CH3OC6H4)PS2-]. The compound 2 has been characterized by using the spectroscopic methods such as IR, H-1, C-13, P-31 NMR and structural analysing method such as X-ray crystallography. It crystallizes in the orthorhombic system, whose space group is P2(1)2(1)2(1). It consists of a dithiophosphonate bridged methoxyphenyl and bis(triflorophenylethyl) groups and a triethylammonium moiety linked by N-H center dot center dot center dot S and C-H center dot center dot center dot F hydrogen bonds. In the crystal structure, the C17H14F6O2PS2 molecule is elongated along the b-axis and stacked along the a-axis. The triethylammonium, N(CH2CH3)(3), molecule fill in the cavities between the C17H14F6O2PS2 molecule. Moreover, ab initio methods based on Hartree-Fock (HF) and Density Functional Theory (DFT) calculations with the basis set of 6-31G(d) are also carried out to determine the molecular structural properties and to calculate FT-IR and NMR spectrum of the compound 2. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement