Fachgruppe Chemie

Synthesis, crystal structure and Hirshfeld analysis of a new crystalline modification of the radical ion salt octamethylenetetrathiafulvalenium triiodide (OMTTF)I₃

2018-10-09T00:00:00Z

Synthesis, crystal structure and Hirshfeld analysis of a new crystalline modification of the radical ion salt octamethylenetetrathiafulvalenium triiodide (OMTTF)I₃ Bof de Oliveira, Adriano; Beck, Johannes; Daniels, Jörg The reaction between 4,5,6,7-tetrahydro-2-(4,5,6,7-tetrahydro-1,3-benzodithiol-2-ylidene)-1,3-benzodithiole (common name: 4,4′,5,5′,6,6′,7,7′-octahydrodibenzotetrathiafulvalene, OMTTF) and an excess of iodine in tetrahydrofuran (THF) yielded the respective radical organic polyiodide salt, C₁₄H₁₆S₄⁺⋅I₃⁻. The asymmetric unit contains one and a half formula unit of both the cation and the anion, with the half-ions completed through inversion symmetry. The (OMTTF^•+) positive charge can be assigned by the bond distances and the planar structure of the C₂S₂C=CS₂C₂ central fragment. In the crystal, trimers of triiodide anions are connected through secondary intermolecular I⋅⋅⋅I interactions into almost linear I₉³⁻ polyanions. The non-centrosymmetric OMTTF radical cations are linked by S⋅⋅⋅S interactions into centrosymmetric dimers, while the centrosymmetric OMTTF cations remain as discrete units. The (OMTTF^•+) radical cations and the triiodide anions are linked by weak C—H⋅⋅⋅I and C—H⋅⋅⋅S interactions into a three-dimensional network. This work reports the fourth crystalline modification of the C₁₄H₁₆S₄^•+⋅I₃⁻ salt. The three previous modifications were obtained from a mixture of acetonitrile and toluene [Konarev et al. (2005). Synth. Met. 151, 231–238].

A new example of intramolecular C—H⋅⋅⋅Ni anagostic interactions

2017-05-19T00:00:00Z

A new example of intramolecular C—H⋅⋅⋅Ni anagostic interactions Bof de Oliveira, Adriano; Beck, Johannes; Brown S. Mellone, Sônia Elizabeth; Daniels, Jörg The reaction of Ni^II acetate tetrahydrate with 4-methyl-2-(1,2,3,4-tetrahydronaphthalen-1-ylidene)hydrazinecarbothioamide in a 2:1 molar ratio and recrystallization from dimethylformamide yielded the title compound, [Ni(C₁₂H₁₄N₃S)₂]⋅C₃H₇NO. The ligands act as monoanionic κ²N¹,S-donors, forming five-membered metallarings. The Ni^II ion is fourfold coordinated in a distorted square-planar cis-configuration, which is rather uncommon for monothiosemicarbazone complexes. Intramolecular H⋅⋅⋅Ni trans-interactions are observed [H⋅⋅⋅Ni distances are 2.50 and 2.57 Å] and thus anagostic interactions can be suggested. The Hirshfeld surface analysis indicates that the major contributions for the crystal packing are H⋅⋅⋅H (66.6%), H⋅⋅⋅S (12.3%) and H⋅⋅⋅C (10.9%) interactions. In the crystal, the complex molecules are linked by dimethylformamide solvent molecules through N—H⋅⋅⋅O interactions into one-dimensional hydrogen-bonded polymers along [010].

Crystal structure of N-ethyl-2-(1,2,3,4-tetrahydronaphthalen-1-ylidene)hydrazinecarbothioamide

2017-01-31T00:00:00Z

Crystal structure of N-ethyl-2-(1,2,3,4-tetrahydronaphthalen-1-ylidene)hydrazinecarbothioamide Bof de Oliveira, Adriano; Beck, Johannes; Landvogt, Christian; de Farias, Renan Lira; Santos Feitoza, Bárbara Regina There are two crystallographically independent molecules in the asymmetric unit of the title compound, C₁₃H₁₇N₃S, one of them being disordered over the methyl group [site-occupancy ratio = 0.705 (5):0.295 (5)]. The maximum r.m.s. deviations from the mean plane of the non-H atoms for the tetralone fragments amount to 0.4572 (17) and 0.4558 (15) Å. The N—N—C—N fragments are not planar and torsion angles are −9.4 (2) and 8.3 (2)°. In the crystal, the molecules are linked by weak N—H⋅⋅⋅S interactions into chains along [100] with graph-set motif C(4) and connected by weak N—H⋅⋅⋅S and C—H⋅⋅⋅S interactions, forming R₂¹(10) rings. The Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are the H⋅⋅⋅H (64.20%), H⋅⋅⋅S (12.60%) and H⋅⋅⋅C (12.00%) interactions. The crystal packing resembles a herringbone arrangement when viewed along [001].

A second crystalline modification of 2-{3-methyl-2-[(2Z)-pent-2-en-1-yl]cyclopent-2-en-1-ylidene}-hydrazinecarbothioamide

2023-11-30T00:00:00Z

A second crystalline modification of 2-{3-methyl-2-[(2Z)-pent-2-en-1-yl]cyclopent-2-en-1-ylidene}-hydrazinecarbothioamide Bof de Oliveira, Adriano; Bresolin, Leandro; Carratu Gervini, Vanessa; Beck, Johannes; Daniels, Jörg A second crystalline modification of the title compound, C₁₂H₁₉N₃S [common name: cis-jasmone thiosemicarbazone] was crystallized from tetrahydrofurane at room temperature. There is one crystallographic independent molecule in the asymmetric unit, showing disorder in the cis-jasmone chain [site-occupancy ratio = 0.590 (14):0.410 (14)]. The thiosemicarbazone entity is approximately planar, with the maximum deviation from the mean plane through the N/N/C/S/N atoms being 0.0463 (14) Å [r.m.s.d. = 0.0324 Å], while for the five-membered ring of the jasmone fragment, the maximum deviation from the mean plane through the carbon atoms amounts to 0.0465 (15) Å [r.m.s.d. = 0.0338 Å]. The molecule is not planar due to the dihedral angle between these two fragments, which is 8.93 (1)°, and due to the sp³-hybridized carbon atoms in the jasmone fragment chain. In the crystal, the molecules are connected by N—H⋅⋅⋅S and C—H⋅⋅⋅S interactions, with graph-set motifs R₂²(8) and R₂¹(7), building mono-periodic hydrogen-bonded ribbons along [010]. A Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are H⋅⋅⋅H (67.8%), H⋅⋅⋅S/S⋅⋅⋅H (15.0%), H⋅⋅⋅C/C⋅⋅⋅H (8.5%) and H⋅⋅⋅N/N⋅⋅⋅H (5.6%) [only non-disordered atoms and those with the highest s.o.f. were considered]. This work reports the second crystalline modification of the cis-jasmone thiosemicarbazone structure, the first one being published recently [Orsoni et al. (2020). Int. J. Mol. Sci. 21, 8681–8697] with the crystals obtained in ethanol at 273 K.

Fachgruppe Chemie

Synthesis, crystal structure and Hirshfeld analysis of a new crystalline modification of the radical ion salt octamethylenetetrathiafulvalenium triiodide (OMTTF)I3

A new example of intramolecular C—H⋅⋅⋅Ni anagostic interactions

Crystal structure of N-ethyl-2-(1,2,3,4-tetrahydronaphthalen-1-ylidene)hydrazinecarbothioamide

A second crystalline modification of 2-{3-methyl-2-[(2Z)-pent-2-en-1-yl]cyclopent-2-en-1-ylidene}-hydrazinecarbothioamide

Synthesis, crystal structure and Hirshfeld analysis of a new crystalline modification of the radical ion salt octamethylenetetrathiafulvalenium triiodide (OMTTF)I₃