Divinyl Sulfone Cross-Linked Cyclodextrin-Based Polymeric Materials: Synthesis and Applications as Sorbents and Encapsulating Agents

The aim of this study was to evaluate the crosslinking abilities of divinyl sulfone (DVS) for the preparation of novel water-insoluble cyclodextrin-based polymers (CDPs) capable of forming inclusion complexes with different guest molecules. Reaction of DVS with native α-cyclodextrin (α-CD), β-cyclodextrin (β-CD) and/or starch generates a variety of homo- and hetero-CDPs with different degrees of crosslinking as a function of the reactants’ stoichiometric ratio. The novel materials were characterized by powder X-ray diffraction, electron microscopy and for their sorption of phenol and 4-nitrophenol. They were further evaluated as sorbents with phenolic pollutants (bisphenol A and β-naphthol) and bioactive compounds (the hormone progesterone and curcumin). Data obtained from the inclusion experiments show that the degree of cross-linking has a minor influence on the yield of inclusion complex formation and highlight the important role of the CDs, supporting a sorption process based on the formation of inclusion complexes. In general, the inclusion processes are better described by a Freundlich isotherm although an important number of them can also be fitted to the Langmuir isotherm with R2 ≥ 0.9, suggesting a sorption onto a monolayer of homogeneous sites

Gold(I) Catalysis Applied to the Stereoselective Synthesis of Indeno[2,1-b]thiochromene Derivatives and Seleno Analogues

A gold(I)-catalyzed cascade reaction for the stereoselective synthesis of sulfur- or selenium-containing indeno[1,2-b]chromene derivatives from o-(alkynyl)styrenes substituted at the triple bond with a thio- or seleno-aryl group is described. The reaction involves a double cyclization process through a proposed key gold−cyclopropyl carbene intermediate that evolves by the intramolecular addition of an aromatic to the cyclopropane ring, affording polycyclic structures. The enantioselective version was studied using gold(I) complexes bearing chiral ligands.We gratefully acknowledge MICINN (PID2020-115789GBC21), “NextGenerationEU/PRTR” (PDC2021-120825-C21), Junta de Castilla y León, and FEDER (BU049P20) for financial support. The project leading to these results also received funding from the “la Caixa” Foundation, under Agreement LCF/PR/PR18/51130007 (CAIXA-UBU001). C.V. and S.S.-P. thank Junta de Castilla y León (Consejería de Educación) and Fondo Social Europeo for postdoctoral contracts

Amino[(1 H

The asymmetric unit of the title salt, C(8)H(10)N(5) (+)·C(7)H(7)O(3)S(−), consists of two amino­[(1H-benzimidazol-2-yl)amino]­meth­an­im­inium cations and two 4-methyl­benzene­sulfonate anions. The cations are each stabilized by intra­molecular N—H⋯N hydrogen bonds between the free amino groups and the imine N atoms of the benzimidazole units, forming S(6) ring motifs. In the crystal, cations and anions are linked by N—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular framework. Two strong π–π stacking inter­actions [centroid–centroid distances = 3.4112 (14) and 3.4104 (14) Å] also occur between the centroids of the imidazole rings of like cations

(4E)-4-[(2-Hydroxyanilino)methylidene]-1-phenylpyrazolidine-3,5-dione dimethyl sulfoxide hemisolvate

The asymmetric unit of the title compound, C16H13N3O3·0.5C2H6OS, is composed of two independent pyrazolidine-3,5-dione molecules and one dimethyl sulfoxide solvent molecule. In each pyrazolidine-3,5-dione molecule, an intramolecular N—H...O hydrogen bond forms an S(5)S(6) motif. In the crystal, pairs of each independent pyrazolidine-3,5-dione molecule are linked by N—H...O hydrogen bonds, forming dimers with R22(8) motifs. These dimers are connected with the other molecules through the solvent molecules via O—H...O hydrogen bonds, forming ribbons along the b-axis direction. C—H...π interactions connect the ribbons. C—H...O interactions also occur

Ethyl 4-anilino-2-methyl-5-oxo-1-phenyl-2,5-dihydro-1H-pyrrole-2-carboxylate

In the title compound, C20H20N2O3, the central 2,5-dihydro-1H-pyrrole ring [r.m.s. deviation = 0.014 (1) Å] is oriented at dihedral angles of 77.81 (6) and 25.33 (6)°, respectively, to the attached phenyl ring and the aniline phenyl ring. An intramolecular N—H...O hydrogen bond occurs. In the crystal, molecules are linked through pairs of N—H...O hydrogen bonds, forming inversion dimers with an R22(10) ring motif. Two weak C—H...π interactions are also observed

Amino[(1H-benzimidazol-2-yl)amino]-methaniminium 4-methylbenzene-sulfonate

The asymmetric unit of the title salt, C8H10N5+center dot C7H7O3S-, consists of two amino[(1H-benzimidazol-2-yl)amino]methaniminium cations and two 4-methylbenzenesulfonate anions. The cations are each stabilized by intramolecular N-H center dot center dot center dot N hydrogen bonds between the free amino groups and the imine N atoms of the benzimidazole units, forming S(6) ring motifs. In the crystal, cations and anions are linked by N-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonds, forming a three-dimensional supramolecular framework. Two strong pi-pi stacking interactions [centroid-centroid distances = 3.4112 (14) and 3.4104 (14) angstrom] also occur between the centroids of the imidazole rings of like cations

Ethyl 4-(4-chloroanilino)-1-(4-chlorophenyl)-2-methyl-5-oxo-2,5-dihydro-1H-pyrrole-2-carboxylate

In the title compound, C20H18Cl2N2O3, the dihedral angles between the central 2,5-dihydro-1H-pyrrole ring and the two phenyl rings are 74.87 (9) and 29.09 (9)degrees. There is a short N-H center dot center dot center dot O contact in the molecule with an S(5) ring motif. In the crystal, pairs of N-H center dot center dot center dot O hydrogen bonds link adjacent molecules into inversion dimers which are reinforced by C-H center dot center dot center dot O hydrogen bonds, forming an R-1(2) (6) R-2(2)(10) R-1(2)(6) ring motif. The dimers are linked by further C-H center dot center dot center dot O hydrogen bonds forming slab-like two-dimensional networks lying parallel to (001)

(Z)-3-(2-Hydroxyethyl)-2-(phenylimino)-1,3-thiazolidin-4-one

In the title compound, C11H12N2O2S, the thiazole and phenyl rings are inclined at 56.99 (6)° to one another. The thiazole ring is planar with an r.m.s. deviation for the five ring atoms of 0.0274 Å. The presence of the phenylimine substituent is confirmed with the C=N distance to the thiazole ring of 1.2638 (19) Å. The molecule adopts a Z conformation with respect to this bond. The –OH group of the hydroxyethyl substituent is disordered over two positions with relative occupancies 0.517 (4) and 0.483 (4). In the crystal, O—H...O hydrogen bonds, augmented by C—H...N contacts, form dimers with R22(11) rings and generate chains along the b axis. Parallel chains are linked in an obverse fashion by weak C—H...S hydrogen bonds. C—H...O hydrogen bonds together with C—H...π contacts further consolidate the structure, stacking molecules along the b axis