Multinuclear complexes or clusters are rarely investigated in medicinal inorganic chemistry although they represent structural intermediates between molecules and nanomaterials. We present in this report two strategies towards Tc-containing clusters. In a pre-assembly approach, the preformed but incomplete cluster fragment [Re (μ -OH) (μ -OH)(CO) ] reacts with [ Tc(CO) ] to the highly stable [ TcRe (μ -OH) (CO) ] cube. The same structure self-assembles when reacting the mononuclear Re and Tc precursors in one pot. Integrating the coordinating OH groups from Schiff bases in this concept leads straight to dinuclear, mixed-metal complexes of the type [ TcRe(μ -O^N-R ) (CO) ] in quantitative yields. Both strategies are unprecedented and open a future path towards clusters, incorporating a Tc radiolabel while being decorated with targeting or cytotoxic moieties.

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C 14 H 19 NO, orthorhombic, P2 1 2 1 2 1 (no. 19), a =6.9081(9) Å, b =7.942(1) Å, c =22.936(3) Å, V =1258.4 Å 3 , Z =4, R gt (F) =0.0496, wR ref (F 2 ) =0.13, T =100 K. Source of materialThetitle compound was synthesized according to literature procedures [1-4] using cyclohexylamine (0.364 g, 3.67 mmol) and 2-hydroxy-4-methylbenzaldehyde (0.500 g, 3.6 mmol) in methanol. The product was obtained as ay ellow powder which was washed with cold methanol and dried. Crystals suitable for X-ray diffraction were obtained from acetone. 64.12, 161.98, 143.92, 131.15, 118.98, 118.17, 116.34, 50.47, 34.03, 32.69, 25.32, 24.48, 24.22, 21.67. Experimental detailsThearomaticHatoms were placed in geometricallyidealized positionsand constrainedtorideontheir parent atoms with U iso (H) =1.2U eq (C). Thealiphatic Hatoms were placed in geometrically idealizedpositions and constrained to ride on their parent atoms with U iso (H) =1 .2U eq (C) and 1.5U eq (C), respectivelyf or the methylene and methyl carbon atoms. The methyl group was generated to fitt he difference electron density and then refined as rigidr otors. Thea bsolutes tructure parameter is meaningless (0(2)) because the compound is aweak anomalous scatterer. DiscussionSchiff bases are capable of forming multiple coordinate bonds, with various transition metal ions. Coordination to the metal atomso ccurst hrough the azomethine group and/orp henolic groups. The coordination chemistry of the Schiff-base metal complexes, in particular the salicylaldimine form [5], has attracted agreat deal of interest due to the wide range of applicationsincluding catalysis, anticancer,antifungaland antibacterial [6][7][8][9]. This research formspart of ongoing studies to investigate the interaction of transition metals, namely rhenium,technetium, copper and rhodium,u sed in radiopharmaceutical drug design and catalysis with N, O and O,O'-bidentate ligands [4, 10-12]. An interesting aspectoffreesalicylaldiminesligand systems are the various possibleconformations which can be adopted in the solid state. Tautomerism between the phenol-imine (O-H×××N) and the keto-amine (O×××H-N) can occur depending on the intramolecular hydrogen bonding [13].T he aromatic Schiff-base group, 2-(phenyliminomethyl)-phenol, are at ypical class of photochromic materials which can undergo both excited state intramolecular proton transfer as well as cis-trans isomerization [3,14,15].R otationa roundt he -C=N-doubleb ondh as been suggested to influencethe thermo-andphotochromic capabilities of this type of molecularsystem.The title compound, 5-methyl-2-(cyclohexyliminomethyl)phenol, crystallized in the orthorhombic spacegroup P2 1 2 1 2 1 ,with four molecules per unit cell.The asymmetricunit consists of one molecule as the trans phenol-iminetautomer. Asingle strong intramolecular hydrogen bond occurs between the O-H group (O1) and N1. The title compound is essentially non-planar with at orsion angle (C1-N1-C21-C22) of 116.0(2)°between the aromatic and cyclohexyl ringsystems.The crystal structure is stabilize...

CCDC no.: 1442787The crystal structure is shown in the gure, Tables 1-3 contain details of the measurement method and a list of the atoms including atomic coordinates and displacement parameters. Source of materialThe title compound was synthesized according to the literature procedures [1, 2] using 1,10-phenanthrolin-5-amine (0.359 g, 1.84 mmol) and 2-hydroxy-4-methylbenzaldehyde (0.254 g, 1.87 mmol) in methanol. The product was obtained as an orange powder which was washed with cold methanol

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