Molecular structure and vibrational and chemical shift assignments of (4R)-5-eno-4,7-epidioxy-3,7-O-methyl-1,2-O-(S)-trichloroethylidene-5,6,8-trideoxy-alpha-D-threo-1,4-furano-4,7-diulo-octose by DFT and ab initio HF calculations

Abstract

Elemental analyses, single crystal X-ray diffraction method, and H-1 and C-13 NMR spectral techniques are used to synthesize and characterize the crystal structure of 4-diethylamino-2-{[4-(3-methyl-3-phenylcyclobutyl)- thiazol-2-yl]-hydrazonomethyl}-phenol. In order to calculate the molecular geometry along with vibrational frequencies and the gauge including atomic orbital (GIAO) H-1 and C-13 NMR chemical shift values of the title crystal structure in the ground state, the Hartree-Fock (HF) and density functional theory (DFT) methods with 6-311G(d,p) basis sets are utilized. The assignments of the vibrational frequencies are calculated with the help of the potential energy distribution (PED) analysis using the VEDA 4 software. Experimental data are used for comparison. The molecule contains C-Ha <-O intra-inter-molecular interactions.