Crystal structure of fac-tricarbonyl-2-((E)-(3-amino-2-hydroxypropylimino) methyl)phenol rhenium(I) toluene solvate, C33H34N4O10Re2

Abstract

Source of materialThecompoundwas prepared upon reacting Re(CO) 5 Cl with the symmetric twofold Schiff-base derived from salicylaldehyde and 1,3-diaminopropan-2-ol in toluene. Crystals suitable forthe diffraction studywereobtaineduponfreeevaporation of thesolvent at room temperature. Experimental detailsCarbon-boundHatoms were placed in calculated positions(C-H 0.95 Åf or aromatic carbon atoms, C-H0 .99Å form ethylene groups andC-H 1.00 Åfor methinegroups) andwereincludedin ther efinementint he riding model approximation, with U iso (H) set to 1.2U eq (C). The Hatoms of the methyl group were allowed to rotate with afixed angle around the C-C bond to best fit the experimental electron density (HFIX 137 in the SHELX program suite [11]), with U iso (H) sett o1 .5U eq (C). The Ha tom of the hydroxylgroup was allowed to rotate with afixed angle around the C-O bond to best fit the experimental electron density (HFIX 147 in the SHELX program suite [11]), with U iso (H) sett o 1.5U eq (O). Both nitrogen-bound Hatomswere located on adifferenceFourier mapand refinedfreely. DiscussionNext to cardiovascular diseases, cancer has become one of the main fatal diseases in industrialized countries. Apart from classicalsurgery,chemo-and radiotherapeutic treatments have entered the arsenal of possible cures for certain types of cancer. All methods, however, suffer from theirown setofproblematic side-effects and, as aconsequence, the development of radio-pharmaceuticals -combining the advantages of chemotherapy as well as radiation methods while at the sametimeavoiding their unique respective undesiredside-effects -has been atopic of research [1,2].T ailoring andf ine-tuning of thee nvisionedr adiopharmaceuticals' properties such as lipophilicityand,inparticular, inertness is of paramountimportancewithrespect to possible future in vivo applications in contemporary medicine and requires sound knowledge about structural parameters of the ligands applied if a more heuristic approach in the synthesis is to triumph over pure trial-and-error as it is encountered in this specific field of coordination chemistry up to the present day. In continuation of our interest in rhenium-based coordination compounds that might serve as radiopharmaceuticals,arhenium(I) starting materialw as reacted with at wofold Schiff-base derived from salicylaldehyde and 1,3-diaminopropan-2-ol. The structural analysis of the compound showed the formation of amononu-clear rhenium(I) coordination compound withamodified ligand system.S imilar compounds featuring acomparable set of donor atomshave been reported in the literature already [3][4][5].The octahedral coordination sphere around the central atom is created by three carbonyl ligands in fac configuration as well as apartially hydrolyzed derivative of the initially two-fold Schiff-base ligand acting as an O,N,N' donor. In addition, half amolecule of toluene is present in the crystal structure of the title compound. The least-squares planes as defined by the respective non-hydrogen atomso ft he phenyl group on the ...

The crystal structure of N-(4-(cyclohexylimino)pent-2-en-2-yl)cyclohexanamine, C17H30N2

“…Imines are easily obtained upon condensation reaction of primary amines with carbonyles (aldehydes and ketones alike). They have found application as ligands in transition metal chemistry, and their role as potential chelating agents has been confirmed on grounds of diffraction studies based on single crystals [7][8][9][10][11]. In continuation of our interest in the structural aspects of diverse imine compounds [12][13][14][15][16][17][18] the title compound was synthesized and investigated by means of a diffraction study based on single crystals.…”