2‐Hydroxy­acetophenone 4‐phenyl­thio­semicarbazone

The title compound, C₁₅H₁₅N₃OS, exists in the thione form and adopts an E configuration about the hydrazine bond, which is in the Z form with respect to the thiocarbonyl bond. An O—H⋯N intra­molecular hydrogen bond promotes planarity in part of the mol­ecule.     

Acetone‐4‐methyl­thio­semicarbazone at 220 K

In the title compound, C₅H₁₁N₃S, the trans conformation is stabilized by a weak intramolecular N—H?N hydrogen bond. Unusually, one N—H bond is not involved in any hydrogen‐bond interactions and instead the mol­ecules form a one‐dimensional polymer via N—H?S intermolecular hydrogen bonds.     

Di‐2‐pyridyl ketone 4‐methyl‐4‐phenyl­thio­semicarbazone

The mol­ecule of the title compound, C₁₉H₁₇N₅S, adopts a Z configuration about the azomethine bond and exists as the thione tautomer. The overall structure of the mol­ecule is distributed in four different planes. An intramolecular hydrogen bond involving the pyridyl N atom and the H atom attached to the hydrazine N atom leads to the formation of a six‐membered ring.     

2‐Hydro­xy‐1‐naphth­aldehyde 2‐methyl­thio­semicarbazone

The potentially tridentate O,N,S‐donor ligand, 2‐hydroxy‐1‐naphth­aldehyde 2‐methyl­thio­semicarbazone, C₁₃H₁₃N₃OS, has been structurally characterized and the mol­ecule is found to exhibit a distorted planar structure with the thio­semicarbazide moiety being twisted slightly out of the plane defined by the naphthyl ring.     

Salicylaldehyde 4,4′‐(hexane‐1,6‐di­yl)­thio­semicarbazone

The title compound, C₁₄H₁₉N₃OS, is in the thio­keto form, with the thione S and hydrazine N atoms cis with respect to each other so that the S atom is involved in inter‐ and intra­molecular hydrogen bonds simultaneously. Inter­molecular C—H⋯S and C—H⋯O hydrogen bonds result in one‐dimensional polymeric chains of mol­ecules along the a axis. A weak C—H⋯π ring inter­action binds the polymeric chains together.     

The stable inner salt 2,2‐dimorpholino‐2‐ethyl­ium‐1‐di­thio­ate

The title compound, C₁₀H₁₆N₂O₂S₂, is considered to maintain an inner‐salt structure in the crystal, where the planes of the carbenium and the thio­carboxyl­ate moieties are nearly perpendicular to each other [77 (2)°], and the backbone C—C bond length [N₂C—CS₂ 1.510 (2) Å] is significantly shorter than a normal C—C single‐bond length.     

4‐(N‐Hydroxy­ethyl‐N‐methyl­amino)­benz­aldehyde thio­semicarbazone

In the crystal structure of the title compound, C₁₁H₁₆N₄OS, the phenyl ring and the thio­semicarbazone moiety from a dihedral angle of 7.7 (1)°. The crystal structure is governed by N—H?O and O—H?S hydrogen bonds leading to the formation of a two‐dimensional network.     

Isatin 3‐semicarbazone and 1‐methyl­isatin 3‐semicarbazone

The two title semicarbazones, namely 2,3‐dihydro‐1H‐indole‐2,3‐dione 3‐semicarbazone, C₉H₈N₄O₂, (I), and 1‐methyl‐2,3‐dihydro‐1H‐indole‐2,3‐dione 3‐semicarbazone, C₁₀H₁₀N₄O₂, (II), show the same configuration, viz. Z around the imine C=N bond and E around the C(O)—NH₂ bond, stabilized by two intra­molecular hydrogen bonds. The presence of a methyl group on the isatin N atom determines the difference in the packing; in (I), the mol­ecules are linked into chains which lie in the crystallographic (102) plane and run perpendicular to the b axis, while in (II), the mol­ecules are arranged to form helices running parallel to a crystallographic screw axis in the a direction.     

Redetermination of 4‐(phenyl)thio­semicarbazide

The structure of the title compound, C₇H₉N₃S, comprises twisted mol­ecules that associate via N—H?N and N—H?S hydrogen‐bonding interactions. The dihedral angle between the phenyl ring and the five‐membered thio­semicarbazide plane is 67.56 (5)°. This structure was previously determined using data from visual estimation of photographic intensity (measurements at room temperature, with R = 0.112).     

A novel thio­cyanate‐bridged dinuclear cadmium(II) complex: di‐μ‐thio­cyanato‐bis­((methanol){4‐nitro‐2‐[2‐(dimethyl­amino)ethyl­imino­meth­yl]phenolato}cadmium(II))

The title complex, [Cd₂(C₁₁H₁₄N₃O₃)₂(NCS)₂(CH₄O)₂], is an inter­esting thio­cyanate‐bridged dinuclear cadmium(II) compound. It is located on a crystallographic inversion center. The Cd^II atom is six‐coordinated in an octa­hedral configuration by one O and two N atoms of one Schiff base ligand and by the terminal N atom of a bridging thio­cyanate ligand, defining the basal plane, and by the terminal S atom of another bridging thio­cyanate ligand and by the O atom of a coordi­nated methanol mol­ecule, occupying the axial positions. The mol­ecules are linked through inter­molecular O—H⋯O hydrogen bonds, forming chains running along the b axis.     

1,3‐Propane­di­ammonium tetra­thio­tungstate and N,N,N′,N′‐tetra­methyl­ethyl­enedi­ammonium tetra­thio­tungstate

The title complexes, (C₃H₁₂N₂)[WS₄] and (C₆H₁₈N₂)[WS₄], contain tetrahedral [WS₄]²⁻ dianions, which accept a complex series of hydrogen bonds from the organic dications. The strength and number of these hydrogen bonds affect the W—S distances.     

2‐Amino‐6‐chloro‐4‐(1‐phenyl­ethyl­amino)­pyrimidine

The structure of the title compound, C₁₂H₁₃ClN₄, (I), comprises a racemic mixture of chiral mol­ecules associated by N—H?N hydrogen‐bonding interactions. The dihedral angle between the two rings is 77.90 (6)°.     

New insight into the photochromic mechanism of 1,3‐diphenyl‐4‐(4‐fluoro)benzal‐5‐pyrazolone N(4)‐phenyl semicarbazone

Density functional theory (DFT) calculation has been carried out to investigate the photochromic mechanism of 1, 3‐diphenyl‐4‐(4‐fluoro)benzal‐5‐pyrazolone N(4)‐phenyl semicarbazone. The novel mechanism, proposed by us, has different reaction pathway between the forward and the reverse process. The energy barrier of the forward direction was calculated to be significantly larger than that of the reverse direction (30.35 kcal/mol to 9.88 kcal/mol), which confirms the experimental observation that the forward process needs irradiation of light while the reverse one will take place easily when heated. The solvent effect on the relative stabilities of those isomers that may involve in the reaction has also been investigated by applying the polarizable continuum model (PCM) of the self‐consistent reaction field theory. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

catena‐Poly[[{4‐bromo‐2‐[2‐(di­methyl­amino)­ethyl­imino­meth­yl]­phenolato}­copper(II)]‐μ‐thio­cyanato]

The title complex, [Cu(C₁₁H₁₄BrN₂O)(NCS)]_n, is an inter­esting thio­cyanate‐bridged polynuclear copper(II) compound, which crystallizes with two independent mol­ecules in the asymmetric unit. Each Cu^II atom is five‐coordinate in a square‐pyramidal configuration, with one O and two N atoms of one Schiff base ligand and one terminal N atom of a bridging thio­cyanate ligand defining the basal plane, and one terminal S atom of another bridging thio­cyanate ligand occupying the apical position. The {4‐bromo‐2‐[2‐(dimethyl­amino)ethyl­imino­meth­yl]phenolato}copper(II) units are linked by the bridging thio­cyanate ligands, forming polymeric chains running along the a axis. There are weak inter­molecular C—H⋯O and C—H⋯S hydrogen bonds between the chains in the crystal structure.     

catena‐Poly­[[bis­(thio­cyanato‐κN)cadmium(II)]‐di‐μ‐thio­urea‐κ4S:S]

The Cd^II ion in the title complex, [Cd(SCN)₂{SC(NH₂)₂}₂]_∞, is situated at a centre of symmetry, and is bound to two N atoms belonging to thio­cyanate groups and to four S atoms of bridging thio­urea ligands. The structure consists of infinite chains of slightly distorted edge‐shared Cd‐centred octahedra. The bridging S atoms of two thio­urea ligands comprise the common edge. Some thermal properties are described.     

4‐Chloro­aceto­phenone [1‐(4‐methoxyphenyl)­ethyl­idene]­hydra­zone

The crystal structure of the title mixed azine, C₁₇H₁₇ClN₂O, contains four independent mol­ecules, A–D, and mol­ecule B is disordered. All four mol­ecules have an N—N gauche conformation, with C—N—N—C torsion angles of 136.5 (4), 137.0 (4), ?134.7 (4) and ?134.7 (4)°, respectively. The phenyl rings are also somewhat twisted with respect to the plane defined by C_ipso and the imine bond. On average, the combined effect of these twists results in an angle of 64.7° between the best planes of the two phenyl rings. Arene–arene double T‐contacts are the dominant intermolecular inter­action. The methoxy‐substituted phenyl ring of one azine mol­ecule interacts to form a T‐contact with the methoxy‐substituted phenyl ring of an adjacent mol­ecule and, similarly, two chloro‐substituted phenyl rings of neighboring mol­ecules interact to form another T‐contact. The only exception is for mol­ecule B, for which the disorder leads to the formation of T‐­contacts between methoxy‐ and chloro‐substituted phenyl rings. The prevailing structural motif of T‐contact formation between like‐substituted arene rings results in a highly dipole‐parallel‐aligned crystal structure.     

S‐[4‐(Tri­methyl­ammonio)­phenyl]thio­sulfate,an aromatic organic thio­sulfate

The title compound, C₉H₁₃NO₃S₂, exists as a zwitterion with crystallographic mirror symmetry. The central S atom of the S₂O₃ group adopts a slightly distorted tetrahedral coordination geometry. The S—S bond length is 2.1137 (7) Å, while the S—O bond lengths are in the range 1.4417 (12)–1.457 (2) Å. The zwitterions in the crystal adopt a head‐to‐tail arrangement, which leads to the formation of a three‐dimensional network through C—H⋯O hydrogen bonds.     

3,4‐Bis[(4‐methoxy­benzo­yl)methyl­sulfanyl]thio­phene

A new type of thio­phene derivative having α‐thio­ketone groups at the 3‐ and 4‐positions, viz. the title compound, C₂₂H₂₀O₄S₃, has been prepared and studied by NMR spectroscopy and single‐crystal X‐ray diffraction techniques. The mol­ecule is nearly planar, the dihedral angles between the essentially planar thio­phene and benzene rings being 9.4 (1) and 10.6 (1)°. One of the thio­ketone O atoms is involved in an inter­molecular C—H⋯O hydrogen‐bonding inter­action.     

Absolute configuration and conformational disorder of a tricyclic thio­semicarbazone derivative

The title compound, (1S,3R,8R)‐2,2‐dichloro‐3,7,7,10‐tetra­methyl­tricyclo­[6.4.0.0^1,3]­dodecan‐11‐one thio­semicarbazone, C₁₇H₂₅Cl₂N₃S, has two disordered conformations of the cyclo­heptane moiety and a screw‐boat conformation for the cyclo­hexene ring. The absolute configuration was established.     

Hexa‐μ2‐chloro‐μ4‐oxo‐tetrakis[(2‐ethyl­tetrazole‐κN4)copper(II)]

In the title molecular complex, [Cu₄Cl₆O(2‐EtTz)₄], where 2‐EtTz is 2‐ethyl­tetrazole (C₃H₆N₄), the central O atom is located on the symmetry site and is tetrahedrally coordinated to four Cu atoms, with Cu—O distances of 1.8966 (4) Å. A very slight distortion of Cu₄O from a regular tetrahedron is observed [two Cu—O—Cu angles are 108.76 (3)° and four others are 109.828 (13)°]. Each Cu atom is connected to three others via the Cl atoms, forming a slightly distorted Cl octahedron around the O atom, with O⋯Cl distances of 2.9265 (7) Å for Cl atoms lying on the twofold axis and 2.9441 (13) Å for those in general positions. The Cu atom has a distorted trigonal–bipyramidal environment, with three Cl atoms in the equatorial plane, and with the N atom of the 2‐ethyl­tetrazole ligand and the μ₄‐O atom in axial positions. The Cu atom is displaced out of the equatorial plane by ca 0.91 Å towards the coordinated N atom of the 2‐­ethyl­tetrazole ligand.