forthcoming articles

The crystal structure of the title complex is stabilized by inter­molecular O—H⋯Cl hydrogen bonds, forming (18) ring motifs.

The title compound is a di­aza­borinane featuring substitution at the 1, 2, and 3 positions of the nitro­gen–boron six-membered heterocycle. In the crystal, mol­ecules are stacked in a head-to-tail manner. The iodide ion makes close contacts with three organic mol­ecules and supports the alternating stack.

The mol­ecule of the title NC_NHCS pincer N-heterocyclic carbene palladium(II) complex, [PdBr(C₂₁H₂₅N₃S)]Br, exhibits a slightly distorted square-planar coordination at the palladium(II) atom, with the five-membered chelate ring nearly planar. The six-membered chelate ring adopts an envelope conformation. Upon chelation, the sulfur atom becomes a stereogenic centre with an R_S configuration induced by the chiral carbon of the precursor imidazolium salt.

The π-conjugated planar title mol­ecules are assembled through C—H⋯π inter­actions between neighboring mol­ecules, resulting in stacking along the c-axis.

The title compound crystallizes in space group P2₁/c with four mol­ecules in the asymmetric unit.

The crystal structure model of germacrone type II determined from single-crystal X-ray data is compared with that of a previous synchrotron X-ray powder study

The title compound features bifurcated template-to-framework N—H⋯(O,O) hydrogen bonds.

The title complex exhibits a distorted octa­hedral geometry about the metal centre, which coordinates two tridentate ligands that are perpendicular to each other.

The structure of bis­[2,3-bis­(thio­phen-2-yl)pyrido[3,4-b]pyrazine]­silver(I) perchlorate methanol disolvate is monoclinic. The Ag atom coordinates pyrido N atoms and is two-coordinate; however, the Ag atom has nearby O atoms that can be assumed to be weakly bonding – one from the perchlorate anion and one from the methanol solvate. One of the thienyl groups of a 2,3-bis­(thio­phen-2-yl)pyrido[3,4-b]pyrazine is flipped disordered and was refined to occupancies of 68.4 (6) and 31.6 (6)%.

The title compound crystallizes in the non-centrosymmetric ortho­rhom­bic space group Fdd2, with 16 mol­ecules in the unit cell. In the crystal, aromatic π–π stacking distance and short C—H⋯O contacts are observed.