Synthesis, crystal structure and fluorescent properties of 1-(4-(dimethylamino)benzylidene)4-(naphthalen-1-yl) thiosemicarbazide

The title compound, 1-4-(dimethylamino)benzylidene)-4-(naphthalene-1-yl) thiosemicarbazide (DMABNTS, C20H20N4S, M-r = 348.47), was synthesized and characterized by elemental analysis, IR, H-1 NMR and MS. The crystal structure of DMABNTS with 1,4-dioxane (Diox, C4H8O2) solvent molecules (DMABNTS(.)2Diox, C28H36N4O4S, M-r = 524.67) was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P2(1)/c with a = 14.418(4), b = 7.1702(19), c = 28.350(7) angstrom, beta = 101.154(6)degrees, V = 2875.4(13) angstrom(3), Z = 4, D-c = 1.212 g/cm, F(000) = 1120 and mu = 0.151 mm(-1). A total of 6458 reflections were collected, of which 4671 were unique. The structure was solved by direct methods and refined to the final R = 0.0732 and wR = 0.2127 for 3921 observed reflections (I > 2 sigma(I)). There exist intermolecular hydrogen bonds (N(2)-H(2B)center dot center dot center dot S(1A) and N(1)-H(1A)center dot center dot center dot O(4B)) in the structure. The study of fluorescent properties shows that DMABNTS emits bright solid-state fluorescence in the visible region and exhibits blue photoluminescence.