Cyanosilylation of aldehydes catalyzed by mixed ligand copper(II) complexes

Synthesis, crystal structure and Hirshfeld surface analysis of bromido-tetra-kis-[5-(prop-2-en-1-yl-sulf-an-yl)-1,3,4-thia-diazol-2-amine-κN3]copper(II) bromide

A novel cationic complex, bromido-tetra-kis-[5-(prop-2-en-1-ylsulfan-yl)-1,3,4-thia-diazol-2-amine-κN 3]copper(II) bromide, [CuBr](C5H7N3S2)4Br, was synthesized. The complex crystallizes with fourfold mol-ecular symmetry in the tetra-gonal space group P4/n. The CuII atom exhibits a square-pyramidal coord-ination geometry. The Cu atom is located centrally within the complex, being coordinated by four nitro-gen atoms from four AAT mol-ecules, while a bromine anion is located at the apex of the pyramid. The amino H atoms of AAT inter-act with bromine from the inner and outer spheres, forming a two-dimensional network in the [100] and [010] directions. Hirshfeld surface analysis reveals that 33.7% of the inter-mol-ecular inter-actions are from H⋯H contacts, 21.2% are from S⋯H/H⋯S contacts, 13.4% are from S⋯S contacts and 11.0% are from C⋯H/H⋯C, while other contributions are from Br⋯H/H⋯Br and N⋯H/H⋯N contacts.

Half-sandwich iridium complexes with hydrazone ligands: preparation, structure, and catalytic synthesis of cyanosilylethers under air

A series of hydrazone-based N,O-chelate half-sandwich iridium complexes were synthesized through a facile route with good yields. These air- and moisture-stable iridium complexes exhibited excellent catalytic activity in the cyanosilylether synthesis under mild reaction conditions. Under the catalysis of iridium, various cyanosilylethers with different substituents were obtained through a one-pot reaction of trimethylsilyl cyanide (TMSCN) with carbonyl substrates, with good to excellent yields. The excellent catalytic efficiency, wide substrate range, and mild reaction conditions made this type of iridium catalyst have the potential for industrial applications. All the half-sandwich iridium complexes were well characterized by IR, NMR, and EA analyses. The molecular structure of iridium complex 1 was confirmed by single-crystal X-ray analysis.

Crystal structure and Hirshfeld surface analysis of 5-(5-phenyl-1,2-oxazol-3-yl)-1,3,4-thia-diazol-2-amine

The title compound, C11H8N4OS, crystallizes with two independent mol-ecules in the asymmetric unit. In the crystal, the N-H⋯N and C-H⋯N hydrogen bonds connect the mol-ecules, generating double layers parallel to the (001) plane. The layers are joined by C-H⋯π inter-actions to form a three-dimensional supra-molecular structure.

Crystal structure and Hirshfeld surface analysis of (E)-1-[2,2-di-chloro-1-(4-methyl-phen-yl)ethen-yl]-2-(4-meth-oxy-phen-yl)diazene

The asymmetric unit of the title compound, C16H14Cl2N2O, comprises two similar mol-ecules, A and B, in which the dihedral angles between the two aromatic rings are 70.1 (3) and 73.2 (2)°, respectively. The crystal structure features short C-H⋯Cl and C-H⋯O contacts and C-H⋯π and van der Waals inter-actions. The title compound was refined as a two-component non-merohedral twin, BASF 0.1076 (5). The Hirshfeld surface analysis and two-dimensional fingerprint plots show that H⋯H (38.2% for mol-ecule A; 36.0% for mol-ecule B), Cl⋯H/H⋯Cl (24.6% for mol-ecule A; 26.7% for mol-ecule B) and C⋯H/H⋯C (20.0% for mol-ecule A; 20.2% for mol-ecule B) inter-actions are the most important contributors to the crystal packing.

Crystal structure and Hirshfeld surface analysis of (Z)-2-amino-4-(2,6-di-chloro-phen-yl)-5-(1-hy-droxy-ethyl-idene)-6-oxo-1-phenyl-1,4,5,6-tetra-hydro-pyridine-3-carbo-nitrile

The mol-ecular conformation of the title compound, C20H15Cl2N3O2, is stabilized by an intra-molecular O-H⋯O hydrogen bond, forming an S(6) ring motif. The central pyridine ring is almost planar [maximum deviation = 0.074 (3) Å]. It subtends dihedral angles of 86.10 (15) and 87.17 (14)°, respectively, with the phenyl and di-chloro-phenyl rings, which are at an angle of 21.28 (15)° to each other. The =C(-OH)CH3 group is coplanar. In the crystal, mol-ecules are linked by inter-molecular N-H⋯N and C-H⋯N hydrogen bonds, and N-H⋯π and C-H⋯π inter-actions, forming a three-dimensional network. The most important contributions to the crystal packing are from H⋯H (33.1%), C⋯H/H⋯C (22.5%), Cl⋯H/H⋯Cl (14.1%), O⋯H/H⋯O (11.9%) and N⋯H/H⋯N (9.7%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (3aR,4S,7S,7aS)-4,5,6,7,8,8-hexa-chloro-2-{6-[(3aR,4R,7R,7aS)-4,5,6,7,8,8-hexa-chloro-1,3-dioxo-1,3,3a,4,7,7a-hexa-hydro-2H-4,7-methano-isoindol-2-yl]hex-yl}-3a,4,7,7a-tetra-hydro-1H-4,7-methano-iso-indole-1,3(2H)-dione

The mol-ecule of the title compound, C24H16Cl12N2O4, is generated by a crystallographic inversion centre at the midpoint of the central C-C bond. A kink in the mol-ecule is defined by a torsion angle of -169.86 (15)° about this central bond of the alkyl bridge. The pyrrolidine ring is essentially planar [max. deviation = 0.014 (1) Å]. The cyclo-hexane ring has a boat conformation, while both cyclo-pentane rings adopt an envelope conformation. In the crystal structure, mol-ecules are linked by inter-molecular C-H⋯O, C-H⋯Cl and C-Cl⋯π inter-actions, and short inter-molecular Cl⋯O and Cl⋯Cl contacts, forming a three-dimensional network.

Crystal structure and Hirshfeld surface analysis of 1,3-bis-{2,2-di-chloro-1-[(E)-phenyl-diazen-yl]ethen-yl}benzene

In the mol-ecule of the title compound, C22H14Cl4N4, the central benzene ring makes dihedral angles of 77.03 (9) and 81.42 (9)° with the two approximately planar 2,2-di-chloro-1-[(E)-phenyl-diazen-yl]vinyl groups. In the crystal, mol-ecules are linked by C-H⋯π, C-Cl⋯π, Cl⋯Cl and Cl⋯H inter-actions, forming a three-dimensional network. The Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (30.4%), C⋯H/H⋯C (20.4%), Cl⋯H/H⋯Cl (19.4%), Cl⋯Cl (7.8%) and Cl⋯C/C⋯Cl (7.3%) inter-actions.

Crystal structure and Hirshfeld surface analysis of dimethyl 5-[2-(2,4,6-trioxo-1,3-diazinan-5-yl-idene)hydrazin-1-yl]benzene-1,3-di-carboxyl-ate 0.224-hydrate

In the crystal, the whole mol-ecule of the title compound, C14H12N4O7·0.224H2O, is nearly planar with a maximum deviation from the least-squares plane of 0.352 (1) Å. The mol-ecular conformation is stabilized by an intra-molecular N-H⋯O hydrogen bond, generating an S(6) ring motif. In the crystal, mol-ecules are linked by centrosymmetric pairs of N-H⋯O hydrogen bonds, forming ribbons along the c-axis direction. These ribbons connected by van der Waals contacts, forming sheets parallel to the ac plane. There are also inter-molecular van der Waals contacts and and C-H⋯π inter-actions between the sheets. A Hirshfeld surface analysis indicates that the most prevalent inter-actions are O⋯H/H⋯O (41.2%), H⋯H (19.2%), C⋯H/H⋯C (12.2%) and C⋯O/ O⋯C (8.4%).

Crystal structure and Hirshfeld surface analysis of ethyl 6'-amino-2'-(chloro-meth-yl)-5'-cyano-2-oxo-1,2-di-hydro-spiro-[indoline-3,4'-pyran]-3'-carboxyl-ate

The mol-ecular conformation of the title compound, C17H14ClN3O4, is stabilized by an intra-molecular C-H⋯O contact, forming an S(6) ring motif. In the crystal, the mol-ecules are connected by N-H⋯O hydrogen-bond pairs along the b-axis direction as dimers with R 2 2(8) and R 2 2(14) ring motifs and as ribbons formed by inter-molecular C-H⋯N hydrogen bonds. There are weak van der Waals inter-actions between the ribbons. The most important contributions to the surface contacts are from H⋯H (34.9%), O⋯H/H⋯O (19.2%), C⋯H/H⋯C (11.9%), Cl⋯H/H⋯Cl (10.7%) and N⋯H/H⋯N (10.4%) inter-actions, as concluded from a Hirshfeld surface analysis.

Crystal structure and Hirshfeld surface analysis of 4,5-di-bromo-2-(4-meth-oxy-phen-yl)-2,3,4,4a,5,6,7,7a-octa-hydro-1H-4,6-ep-oxy-1H-cyclo-penta-[c]pyridin-1-one

The mol-ecule of the title compound, C15H15Br2NO3, comprises a fused tricyclic system consisting of two five-membered rings (cyclo-pentane and tetra-hydro-furan) and one six-membered ring (tetra-hydro-pyridinone). Both five-membered rings of the tricyclic system have envelope conformations, and the conformation of the six-membered cycle is inter-mediate between chair and half-chair. In the crystal, the mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π, C-Br⋯π and C⋯O inter-actions into double layers. The layers are connected into a three-dimensional network by van der Waals inter-actions.

(3aS,4R,5R,6S,7aR)-4,5-Di-bromo-2-[4-(tri-fluoro-meth-yl)phen-yl]-2,3,3a,4,5,6,7,7a-octa-hydro-3a,6-ep-oxy-1H-isoindol-1-one: crystal structure and Hirshfeld surface analysis

The asymmetric unit of the title compound, C15H12Br2F3NO2, consists of two crystallographically independent mol-ecules. In both mol-ecules, the pyrrolidine and tetra-hydro-furan rings adopt an envelope conformation. In the crystal, mol-ecule pairs generate centrosymmetric rings with R 2 2(8) motifs linked by C-H⋯O hydrogen bonds. These pairs of mol-ecules form a tetra-meric supra-molecular motif, leading to mol-ecular layers parallel to the (100) plane by C-H⋯π and C-Br⋯π inter-actions. Inter-layer van der Waals and inter-halogen inter-actions stabilize mol-ecular packing. The F atoms of the CF3 groups of both mol-ecules are disordered over two sets of sites with refined site occupancies of 0.60 (3)/0.40 (3) and 0.640 (15)/0.360 (15). The most important contributions to the surface contacts of both mol-ecules are from H⋯H (23.8 and 22.4%), Br⋯H/H⋯Br (18.3 and 12.3%), O⋯H/H⋯O (14.3 and 9.7%) and F⋯H/H⋯F (10.4 and 19.1%) inter-actions, as concluded from a Hirshfeld surface analysis.

Crystal structure and Hirshfeld surface analysis of 3-cyano-4-hy-droxy-2-(4-methyl-phen-yl)-6-oxo-N-phenyl-4-(thio-phen-2-yl)cyclo-hexane-1-carbox-amide 0.04-hydrate

In the title compound, C25H22N2O3S·0.04H2O, the central cyclo-hexane ring adopts a chair conformation. In the crystal, mol-ecules are linked by N-H⋯O, C-H⋯O, and C-H⋯N hydrogen bonds, forming the mol-ecular layers parallel to the bc plane, which inter-act by the van der Waals forces between them. A Hirshfeld surface analysis indicates that the contributions from the most prevalent inter-actions are H⋯H (41.2%), C⋯H/H⋯C (20.3%), O⋯H/H⋯O (17.8%) and N⋯H/H⋯N (10.6%).

Crystal structure and Hirshfeld surface analysis of (RS)-3-hy-droxy-2-{[(3aRS,6RS,7aRS)-2-(4-methyl-phenyl-sulfon-yl)-2,3,3a,6,7,7a-hexa-hydro-3a,6-ep-oxy-1H-isoindol-6-yl]meth-yl}isoindolin-1-one

The title compound, C24H24N2O5S, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In the central ring systems of both mol-ecules, the tetra-hydro-furan rings adopt envelope conformations, the pyrrolidine rings adopt a twisted-envelope conformation and the six-membered ring is in a boat conformation. In mol-ecules A and B, the nine-membered groups attached to the central ring system are essentially planar (r.m.s. deviations of 0.002 and 0.003 Å, respectively). They form dihedral angles of 64.97 (9) and 56.06 (10)°, respectively, with the phenyl rings. In the crystal, strong inter-molecular O-H⋯O hydrogen bonds and weak inter-molecular C-H⋯O contacts link the mol-ecules, forming a three-dimensional network. In addition weak π-π stacking inter-actions [centroid-to centroid distance = 3.7124 (13) Å] between the pyrrolidine rings of the nine-membered groups of A mol-ecules are observed. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to qu-antify the inter-molecular inter-actions present in the crystal, indicating that the environments of the two mol-ecules are very similar. The most important contributions for the crystal packing are from H⋯H (55.8% for mol-ecule A and 53.5% for mol-ecule B), O⋯H/H⋯O (24.5% for mol-ecule A and 26.3% for mol-ecule B) and C⋯H/H⋯C (12.6% for mol-ecule A and 15.7% for mol-ecule B) inter-actions.

Crystal structure and Hirshfeld surface analysis of 2-benzyl-4,5-di-bromo-2,3,3a,4,5,6,7,7a-octa-hydro-3a,6-ep-oxy-1H-isoindol-1-one

The title compound, C15H15Br2NO2, crystallizes with two mol-ecules in the asymmetric unit of the unit cell. In both mol-ecules, the tetra-hydro-furan rings adopt an envelope conformation with the O atom as the flap and the pyrrolidine rings adopt an envelope conformation. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming sheets lying parallel to the (002) plane. These sheets are connected only by weak van der Waals inter-actions. The most important contributions to the surface contacts are from H⋯H (44.6%), Br⋯H/H⋯Br (24.1%), O⋯H/H⋯O (13.5%) and C⋯H/H⋯C (11.2%) inter-actions, as concluded from a Hirshfeld surface analysis.

Crystal structure and Hirshfeld surface analysis of 4,5-di-bromo-6-methyl-2-phenyl-2,3,3a,4,5,6,7,7a-octa-hydro-3a,6-ep-oxy-1H-isoindol-1-one

In the title compound, C15H15Br2NO2, two bridged tetra-hydro-furan rings adopt envelope conformations with the O atom as the flap. The pyrrolidine ring also adopts an envelope conformation with the spiro C atom as the flap. In the crystal, the mol-ecules are linked into dimers by pairs of C-H⋯O hydrogen bonds, thus generating R 2 2(18) rings. The crystal packing is dominated by H⋯H, Br⋯H, H⋯π and Br⋯π inter-actions. One of the Br atoms is disordered over two sites with occupation ratio of 0.833 (8):0.167 (8).

Crystal structure and Hirshfeld surface analysis of ethyl (4R,4aS)-2-methyl-5,8-dioxo-6-phenyl-4a,5,6,7,7a,8-hexa-hydro-4H-furo[2,3-f]iso-indole-4-carboxyl-ate

In the title compound, C20H19NO5, the central six-membered ring has a slightly distorted half-chair conformation, with puckering parameters of Q T = 0.3387 (11) Å, θ = 49.11 (19)° and φ = 167.3 (2)°. The conformation of the fused pyrrolidine ring is that of an envelope. Mol-ecules are connected by inter-molecular C-H⋯O hydrogen bonds, C-H⋯π inter-actions and π-π stacking inter-actions [centroid-to-centroid distance = 3.9536 (11) Å, with a slippage of 2.047 Å], forming a three-dimensional network. The most important contributions to the surface contacts are from H⋯H (46.3%), O⋯H/H⋯O (31.5%) and C⋯H/H⋯C (17.3%) inter-actions, as concluded from a Hirshfeld surface analysis.

Activation of the Cyano Group at Imidazole via Copper Stimulated Alcoholysis

Reactions of 4,5-dicyano-1-methylimidazole with CuX2 (X = Cl, Br) in alcohol solvents (ethanol and methanol) resulted in the formation of Cu(II) carboximidate complexes [CuCl2(5- cyano-4-C(OEt)N-1-methylimidazole)(EtOH)] (1), [Cu2(µ-Cl)2Cl2(5-cyano-4-C(OMe)N-1-methylimidazole)2] (2), [Cu2(µ-Br)2Br2(5-cyano-4-C(OMe)N-1-methylimidazole)2] (3), and [Cu2(µ-Br)2Br2(5-cyano-4-C(OEt)N-1-methylimidazole)2] (4). The structures were determined by the X-ray crystallographic method, and further spectroscopic and computational methods were employed to explain the structural features. The solvent contributed to the alcoholysis reaction of the cyano group, as the result of which the ligand coordinated to the metal center in bidentate mode forming a five-membered chelating ring. In 1, the solvent also acts as an additional ligand, which coordinates to the metal center of a monomeric complex. In compounds 2–4, two halogen ligands link the metal atoms forming dihalo-bridged copper dimers. The infrared absorption characteristics were verified by simulation of the infrared spectra at the density functional theory level. In addition, the electronic absorption characteristics were explained by simulation of the UV–Vis spectra using the TD-DFT method. Molecular modelling at the DFT level was performed to study the effects of halogen type and steric hindrance of the alkoxy groups in forming the copper(II) complexes.

Crystal structure and Hirshfeld surface analysis of (E)-3-[(2,3-di-chloro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide

In the cation of the title salt, C16H14Cl2N3S+·Br-, the central thia-zolidine ring adopts an envelope conformation. The phenyl ring is disordered over two sites with a refined occupancy ratio of 0.541 (9):0.459 (9). In the crystal, C-H⋯Br and N-H⋯Br hydrogen bonds link the components into a three-dimensional network with the cations and anions stacked along the b-axis direction. Weak C-H⋯π inter-actions, which only involve the minor disorder component of the ring, also contribute to the mol-ecular packing. In addition, there are also inversion-related Cl⋯Cl halogen bonds and C-Cl⋯π (ring) contacts. A Hirshfeld surface analysis was conducted to verify the contributions of the different inter-molecular inter-actions.

Crystal structure and Hirshfeld surface analysis of 3,3',3''-[(1,3,5-triazine-2,4,6-tri-yl)tris-(-oxy)]tris-(5,5-di-methyl-cyclo-hex-2-en-1-one)

The three cyclo-hexenone rings of the title compound, C27H33N3O6, adopt slightly distorted envelope conformations, with the C atom bearing two methyl groups as the flap atom in each case. These cyclo-hexenone mean planes form dihedral angles of 87.41 (11), 70.73 (11) and 70.47 (11)° with the 1,3,5-triazine ring, while the dihedral angle between the cyclo-hexenone mean planes are 57.52 (12), 23.75 (12) and 53.21 (12)°. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming a three-dimensional network.

Packing polymorphism in 3-amino-2-pyrazinecarboxylate based tin(ii) complexes and their catalytic activity towards cyanosilylation of aldehydes

3-Amino-2-pyrazinecarboxylic acid is used to synthesize two new mononuclear interconvertible packing polymorphs of tin(ii) which act as heterogeneous catalysts for the cyanosilylation of aldehydes with trimethylsilyl cyanide.