A series of new charge-transfer cocrystals of F2TCNQ with anthracene, tetracene, and chrysene was prepared and characterized. The donor and acceptor molecules are arranged in alternating D–A–D–A stacks. The linear acenes in combination with F2TCNQ form layered structures due to in-plane lateral donor–acceptor and acceptor–acceptor interactions via multiple C–H···N and C–H···F hydrogen bonds, which govern the crystal structure and significantly alter face-to-face π–π interactions. In the cocrystal of F2TCNQ with chrysene no interactions between acceptor molecules are observed, and the π–π interactions prevail. Thus, the donor–acceptor interplanar distance is the smallest in the chrysene complex despite its lower energy level of the HOMO and weaker donor ability, as determined through electrochemical oxidation potentials in this series of PAHs. The charge-transfer values estimated through empirical correlations and QTAIM analysis also do not manifest a direct dependence on the donor ability of PAHs. Thus, though face-to-face π–π interactions dictate the formation of cocrystals, the lateral noncovalent interactions are as important for the supramolecular arrangement and charge transfer. UV/vis spectroscopy and electronic structure quantum chemical calculations show that these cocrystals may be classified as small-gap semiconductors with energy gaps of 0.7–1.3 eV.

A new diastereoselective synthesis of alpha-aminophosphonates has been developed, based on the reaction, in the presence of trifluoroacetic acid, of trialkyl phosphites with chiral imines derived from (R)- or (S)-1-(alpha-aminobenzyl)-2-naphthol. The reaction proceeds at room temperature in toluene with high diastereoselectivity. The major diastereomer can be separated by crystallization from an appropriate solvent. The relative configuration of both chiral centers of the major diastereomer was determined by single-crystal X-ray structure analysis. The desired alpha-aminophosphonic acids can be obtained in enantiopure form by treatment of the corresponding diastereomers with HCl.

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An improved method for enantioseparation of racemic 1-(a-aminobenzyl)-2-naphthols has been developed by the reaction in situ of Betti base product mixtures with L-(+)-tartaric acid taken in a 1:1 ratio. The products of this reaction are (-)-1-(a-aminobenzyl)-2-naphthol tartrate, the acetal of benzaldehyde and tartaric acid as well as (+)-1,3-diaryl-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazine, which can be easily separated by crystallization.

The possibility was demonstrated to use metal coordination for the resolution of racemic chiral N-thiophosphorylated thioureas through controlling the stereochemistry of the complex formation and supramolecular chiral recognition during crystallization. A series of new Ni(II) complexes derived from chiral N-thiophosphorylated thioureas with 1,3-N,S-coordination were synthesized in enantiopure and racemic forms and characterized by X-ray single crystal diffraction. It was shown that square-planar centrosymmetric nickel ion coordination results in exclusive formation of meso-complexes from racemic ligands. The symmetry break of the nickel ion coordination by the introduction of pyridine co-ligand into the apical position promotes chiral recognition of the ligands upon complexation with formation of exclusively homochiral complexes. Further supramolecular recognition might be achieved by variation of crystal growth conditions, with racemic crystals being obtained at higher initial concentrations, including two polymorphs with homochiral and heterochiral supramolecular chains formed via intermolecular C−H•••Ni interactions. Crystal growth from the dilute solutions results in resolution of enantiomers and formation of conglomerates. Crystallization was shown to be determined by the conformational flexibility of the ligands. Racemic Ni(II) complexes showed a notable cytotoxic effect on the M-Hela cancer cell line with absolutely no toxicity on the normal cell line Chang liver.

The interaction of manganese phthalocyanine with F4-TCNQ is accompanied by the transformation of the acceptor molecule into a new organic ligand, the 4-(dicyanomethanido)tetra-fluorobenzoate dianion, resulting in the formation of a unique Mn III charge-transfer complex, in which two Mn phthalocyanine moieties are bridged by the dianion, with parallel arrangement of all aromatic fragments and an interplanar distance of 3.30 Å. The formation of the complex takes place in a 2:1 ratio, with the two electrons transferring from two donor molecules to an acceptor molecule. Magnetic measurements [a] A. E. ported so far; however, several complexes with structurally similar metal-porphyrin derivatives are known. They involve charge-transfer complexes with π-stacking interactions between the donor and acceptor molecules [12] and those with metal-N≡C coordination bonds between metal-porphyrins and TCNQ derivatives. [13] Similar results should possibly be expected for metal-phthalocyanine complexes.Our attempts to grow mixed single crystals of MnPc and F4-TCNQ from solution resulted in a quite unexpected reaction between the components and a new type of complex. Herewith, we report these new complexes, their structure, and their electrochemical and magnetic properties. Results and Discussion SynthesisThe main problem of growing CT multicomponent single crystals from solution is the poor solubility of phthalocyanines. [14] We chose N-methyl-2-pyrrolidone (NMP) and 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidin-7-one (DMPU) as solvents suitable for both the donor and acceptor components.The first step to grow bicomponent crystals was naturally performed in the moisture-free conditions that are most consistent with those used for the preparation of thin films. [10] However, no single crystals suitable for single-crystal X-ray diffraction study could be grown from dry solvents. Instead, the crystallization appeared to be possible by slow diffusion of water into the reaction mixtures. The reaction products obtained in the two solvents NMP and DMPU are quite different.The crystallization from NMP produces two types of crystals, 1 and 2. Their structure was studied by single-crystal X-ray diffraction. The results appear to be quite unexpected (Scheme 1).Both compounds contain the Mn III Pc framework, as well as the aromatic 4-(dicyanomethanido)tetrafluorobenzoate dianion, obviously being transformed from pristine F4-TCNQ. The first compound (1) has a salt-like structure, composed of Mn III Pc, coordinated by the 4-(dicyanomethanido)tetrafluorobenzoate dianion, and the cation of Mn III Pc, coordinated by two water molecules.Scheme 1. Interaction of MnPc with F4-TCNQ in NMP.

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Single crystals of Mn(iii)Pc·2H2O with TCNQ/F4-TCNQ radical anions are stabilized via C–H⋯π interactions. Mn(iii) is in a high spin state.