South African Journal of Chemistry
On-line version ISSN 1996-840X
THAKAR, Amit S.; FRIEDRICH, Holger B.; JOSHI, Krishnalal T. and MAGUIRE, Glenn E.M.. Isolation, characterization and x-ray structure determination of the schiff base ligand: 5-methyl-2-phenyl-4-[phenyl-(4-phenyl-thiazol-2-ylamino)-methylene]-2,4-dihydro-pyrazol-3-one. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp. 39-44. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a6.
The structure of the amine tautomer of the new Schiff base derived from 4-benzoyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one (2) and 4-phenyl-thiazol-2-ylamine (3) was confirmed by means of single crystal X-ray diffraction. The title compound (4) was synthesized and crystals were grown from a mixture of dichloromethane and n-hexane (1:3). Single crystal X-ray diffraction analysis show that the structure is primarily stabilized by strong intramolecular N3-H3A-O1 hydrogen bonds [N3-H3A = 0.883(19) Ẳ, H3A-O1 = 1.925(18) Ẳ, N3-O1 = 2.6901(13) A, with an angle for N3-H3A-O1 = 144.1(17) °] and this leads to the formation of a pseudo nine-membered hydrogen bonded pattern. Elemental analysis, FTIR and NMR analyses have been employed to characterize the crystal.
Keywords : Pyrazolone; thiazole; Schiff base; tautomer; X-ray structure.