312 research outputs found
Ethyl 5-hydroxy-6-oxo-4-phenyl-5,6-dihydro-4H-cyclopenta[b]thiophene-5-carboxylate
In the title molecule, C16H14O4S, the dihydrocyclopentathiophenone ring system is almost planar, with an r.m.s. deviation of 0.060 Å from the best fit plane through all nine non-H atoms. The cyclopentanone ring adopts a severely flattened envelope conformation with the C atom carrying the OH and ethylcarboxylate substituents at the flap. This atom lies only 0.185 (3) Å from the plane through the other four C atoms. The phenyl substituent is inclined at 43.37 (5)° to the dihydrocyclopentathiophenone mean plane. In the crystal, molecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with R
2
2(10) ring motifs. Weak C—H⋯O hydrogen bonds also link molecules into chains along c, while an approximately orthogonal set of C—H⋯O contacts form chains along b, resulting in layers lying parallel to (100). Inversion dimers also form through weaker R
2
2(12) C—H⋯S contacts, which combine with C—H⋯O contacts to form stacks along b
1,4-Bis(iodomethyl)benzene
The centrosymmetric title compound, C8H8I2, was prepared by metathesis from the dibromo analogue. In the crystal structure, weak C—H⋯I interactions link the molecules into stacks down the b axis. The structure is further stabilized by short I⋯I contacts [3.8433 (2) Å], forming undulating sheets in the (101) plane
6-Hydroxy-5,7,8-trimethylchroman-2-one
The title compound, C12H14O3, consists of a chromanone unit with an –OH substituent at the 4-position and methyl substituents on the remaining C atoms of the aromatic ring. The fused pyranone ring adopts a distorted envelope conformation with the methylene group adjacent to the carbonyl carbon as the flap atom. The crystal structure is stabilized by classical O—H⋯O hydrogen bonds and weak C—H⋯O and C—H⋯π interactions, generating a three-dimensional network
The preparation and characterisation of monomeric and linked metal carbonyl clusters containing the closo-Si2Co4 pseudo-octahedral core
PhSiH3 reacts with [Co₄(CO)₁₂] at 50 °C in hydrocarbon solvents to give [(µ₄-SiPh)₂Co₄(CO)₁₁], 2c, shown by an X-ray crystal structure determination to have a pseudo-octahedral Si₂Co₄ core. Substituted aryl-silanes behaved similarly. Mixtures of PhSiH₃, H₃SiC₆H₄SiH₃ and [Co₄(CO)₁₂] in a ca. 2 1 2 ratio gave the dimeric cluster [{Co₄(µ₄-SiPh)(CO)₁₁Si}₂C₆H₄], 3a, which has the two Si₂Co₄ cores linked by a C₆H₄ group to give a rigid molecule which an X-ray structure analysis shows to be over 23 Å long. Related dimers linked by –(CH₂)₈– groups were isolated from mixtures of PhSiH₃, α ,ω-(H₃Si)₂(CH₂)₈ and [Co₄(CO)₁₂]. Electrochemical studies show the two cluster units in 3a do not interact electronically
4-[(E)-2-Ferrocenylethenyl]-1,8-naphthalic anhydride
In the structure of the title compound, [Fe(C5H5)(C19H11O3)], the plane of the substituted ferrocene ring is tilted by 14.17 (6)° with respect to the mean plane through the naphthalene ring system. In the crystal structure, centrosymmetric dimers are formed through π–π interactions [centroid–centroid distance = 3.624 (2) Å] between the substituted ferrocene ring and the three fused rings of the naphthalic anhydride unit. Pairs of dimers are held together by further naphthalene–naphthalene π–π interactions [distance between parallel mean planes 3.45 (3) Å]. Each dimer interacts with four neighbouring dimers in a herringbone fashion through C—H⋯π interactions, so forming a two-dimensional sheet-like structure
Gel actuators based on polymeric radicals
Low-voltage electrochemical actuation of radical polymer gels has been demonstrated in an organic electrolyte. Polymer gels were prepared by post-modification of active-ester precursor gels with an amine-functionalised radical. A combination of few-layer graphene and multiwall carbon nanotubes gave high conductivity and improved actuation in the gels, with 32% linear actuation. The actuator system showed good stability over at least 10 cycles, showing its promise. The cycle time was several hours due to mass-transport limited transport of ions and solvent into the device
4-(Dimethylamino)pyridinium 4-toluenesulfonate
In the title compound, C7H11N2
+·C7H7O3S−, the cation is protonated at the N atom of the heterocyclic ring. The dimethylamino group lies close to the pyridinium ring plane with a dihedral angle between the pyridinium and the dimethylamine CNC planes of 3.82 (17)°. The N—C bond linking the dimethylamino substituent to the pyridinium ring is characteristically short [1.3360 (19) Å], suggesting some delocalization in the cation. In the crystal structure, N—H⋯O hydrogen bonds link individual pairs of cations and anions. The structure is further stabilized by an extensive series of C—H⋯O hydrogen bonds, augmented by π–π [centroid–centroid distance between adjacent pyridinium rings = 3.5807 (10) Å] and C—H⋯π interactions, giving a network structure
(Carbonyl-1κC)bis[2,3(η5)-cyclopentadienyl][μ3-(S-methyl trithiocarbonato)methylidyne-1:2:3κ4 C,S′′:C:C](triphenylphosphine-1κP)(μ3-sulfido-1:2:3κ3 S)dicobalt(II)iron(II) trifluoromethanesulfonate
The asymmetric unit of the title compound, [FeCo2(C5H5)2(C3H3S3)S(C18H15P)(CO)]CF3SO3, consists of a triangular irondicobalt cluster cation and a trifluoromethanesulfonate anion. In the cation, the FeCo2 triangle is symmetrically capped on one face by an S atom and on the other by a C atom linked to a methyl trithiocarbonate residue that bridges the Fe—C bond. Each Co atom carries a cyclopentadienyl ligand while the Fe atom coordinates to one carbonyl and one triphenylphosphine ligand. In the crystal structure, the cation is linked to the anion by a number of weak non-classical C—H⋯O and C—H⋯F hydrogen bonds and weak S⋯O (3.317 Å) and S⋯F (3.198 Å) interactions. The structure is further stabilized by additional intermolecular C—H⋯O, C—H⋯F and O⋯O (2.942 Å) contacts, together with an unusual S⋯π(Cp) interaction (S⋯centroid distance = 3.385 Å), generating an extended network
N-(1-Acryloyl-2,2,6,6-tetramethylpiperidin-4-yl)acrylamide
The title compound, C15H24N2O2, crystallizes with two unique molecules, (I) and (II), in the asymmetric unit, differing in the orientation of the acryloyl units with respect to the piperidine rings. The acrylamide units are essentially planar in both molecules (r.m.s. deviations = 0.042 and 0.024 Å, respectively), as are the C3N chains of the acryloyl units. The carbonyl O atoms of the acryloyl systems lie significantly out of these planes, viz. by −0.171 (9) Å for molecule (I) and by 0.33 (1) Å for molecule (II). The acrylamide and acryloyl planes are inclined at 68.7 (4)° and 59.8 (3)° in the two molecules. The piperidine rings each adopt twist boat conformations. In the crystal, strong N—H⋯O hydrogen bonds link the molecules into zigzag C(4) chains along b. Additional C—H⋯O contacts result in the formation of stacks along a
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