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The combination of one dipyridyl linker [1,2-di(4-pyridyl)ethylene (DPE), 1,2-di(4-pyridyl)ethane (DPEt), or 4,4′-azopyridine (DPA)] with two molecules of arylboronate ester 1 produced dinuclear Lewis-type N→B adducts that can act as acyclic host for polycyclic aromatic hydrocarbons (PAHs) in the solid state. Nine crystalline solids of composition PAH@adduct (i.e., one PAH per adduct) were obtained from solutions containing a single PAH. On the basis of the single-crystal X-ray diffraction analysis of the compound ANT@A1 (ANT = anthracene; A1 = adduct being composed of DPE and two boronate esters 1), the PAH inclusion selectivity is related to a size-fitting adaptation to an octaedral-shaped pocket assembled by CH-π interactions between fragments of the diamine and the arylboronate ester 1. The resulting reversible organic clathrates can perform “catch and release” cycles of PAHs such as pyrene and can sequester selectively PAHs from mixtures in solution.

The combination of racemic praziquantel, (RS)-PZQ, with aliphatic dicarboxylic acids of the homologous series HOOC–(CH2)n–COOH (with n = 0–8) and the unsaturated analogues of succinic acid as cocrystal formers via liquid-assisted grinding provided a total of nine 1:1 and 2:1 cocrystals with oxalic acid, malonic acid, succinic acid (two polymorphic phases), maleic acid, fumaric acid, glutaric acid, adipic acid, and pimelic acid. The cocrystalline phases were identified first by XRPD analysis and then structurally characterized by IR spectroscopy and, as far as possible, by single-crystal X-ray diffraction analysis. Crystals suitable for XRD analysis were obtained for seven cocrystals and, additionally, for (RS)-PZQ. The analysis of the supramolecular interactions in the crystal structures has shown that the dominant hydrogen bonding patterns within the cocrystals are heterodimeric motifs formed through O–H···O hydrogen bonds between PZQ and the dicarboxylic acids, which mostly contain additionally at least...

Five metal complexes have been prepared by reacting 3- and 4-pyridineboronic acid (3- and 4-pba) with potassium tetrachloroplatinate (K2PtCl4) and hexachloroplatinic(IV) acid hydrate (H2PtCl6·aq): [4-pbaH]2[PtCl4], [3-pbaH]2[PtCl4], [4-pbaH][Pt(4-pba)Cl3], cis-[Pt(4-pba)2Cl2]·H2O, and cis-[PtIV(3-pba)2Cl4]·2H2O. All compounds have been characterized by single-crystal X-ray diffraction analysis, showing that the primary hydrogen bonding interactions of the resulting 1D, 2D, and 3D networks contain at least one of the following synthons: X-H···Cl2Pt− (X = C, N+), B(OH)2···Cl2Pt−, and B(OH)2···(HO)2B. The dimensions are enhanced further by secondary +N−H···ClPt, O−H···O, and O−H···ClPt hydrogen bonding interactions between donor and acceptor atoms located at the periphery of these synthons. Additional weak C−H···O, C−H···Cl, B···N, and π···π stacking interactions stabilize the crystal structures further.