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The reaction of CuI with dialkylcyanamides yielded copper(I) cluster complexes [Cu4I4(NCNR2)4] (R2 = Me2, Et2, C4H8, C5H10, C4H8O), as well as coordination polymer catena-[CuI(NCNMe2)]n. The structures of the obtained compounds were determined by single-crystal X-ray diffraction analysis, atomic emission spectroscopy (Cu), CHN elemental analysis, X-ray phase analysis, and IR spectroscopy. The prepared clusters luminesce at room temperature in the solid state with an emission maximum in the range of 554–600 nm upon irradiation at 365 nm. [ABSTRACT FROM AUTHOR]

Two complexes trans -[Co(NCNMe 2 ) 2 (H 2 O) 4 ]X 2 ·2H 2 O ([ 1 ]X 2 ·2H 2 O; X = Cl, Br) were prepared by the reaction of CoX 2 ·6H 2 O with 2 equiv of NCNMe 2 in methanol and isolated in excellent (98%) yields. The complexes were characterized by elemental analyses (C, H, N), high resolution ESI, IR spectroscopies, and their molecular structures were determined by a single-crystal X-ray diffraction. In [ 1 ]X 2 ·2H 2 O, the hydrogen bonding between the counterions X − and both ligated and crystallization water molecules responsible for the formation of a 3D-network. Based on quantum chemical DFT calculations and topological analysis of the electron density distribution within the formalism of Bader’s theory (AIM method) these interactions can be classified as weak (HO–H⋯X − , X − ⋯H–OH, and HO–H⋯X − contacts, 2.5–3.5 kcal/mol) and moderate (HO–H⋯OH 2 contacts, 5.7–6.3 kcal/mol) strength hydrogen bonds mainly due to electrostatics. [ABSTRACT FROM AUTHOR]

The complexes [Ni(NCNAlk 2 ) 2 (H 2 O) 4 ]X 2 ([ 1 ]X 2 –[ 2 ]X 2 ; X = Cl, Br; Alk 2 = Me 2 [ 1 ] 2+ , C 4 H 8 O [ 2 ] 2+ ) were prepared by the reaction of NiX 2 · n H 2 O (X = Cl, n = 0; Br, n = 3) with 2 equivs NCNAlk 2 (Alk 2 = Me 2 , C 4 H 8 O) in methanol at 20–25 °C for 1 d. The complex [Ni(NCNMe 2 ) 4 (H 2 O) 2 ]I 2 ([ 3 ]I 2 ) was synthesized by treatment of NiI 2 ·6H 2 O with 4 equivs NCNMe 2 in MeOH at 20–25 °C for 1 d. All dialkylcyanamide complexes were characterized by elemental analysis (Ni), high resolution ESI + -MS, IR spectroscopy, and X-ray diffraction. Complexes [ 1 ]X 2 –[ 2 ]X 2 bearing two coordinated dialkylcyanamides crystallize in the two isomeric forms, viz. trans - and cis- ( N , N ). The trans- ( N , N )-isomers were characterized by X-ray crystallography for [ 1 ]Cl 2 ·2H 2 O, [ 1 ]Br 2 ·2H 2 O, [ 2 ]Cl 2 ·4H 2 O and the cis -( N , N )-isomers for [ 2 ]Cl 2 ·2H 2 O and [ 2 ]Br 2 ·2H 2 O. [ABSTRACT FROM AUTHOR]

Highlights: [•] Coordination modes and synthetic routes to dialkylcyanamide (NCNAlk2) complexes are reviewed. [•] Structural features, properties, and reactivity modes of NCNAlk2 ligands are systemized. [•] In many instances metal-bound NCNAlk2exhibit different behavior to conventional NCR nitriles. [Copyright &y& Elsevier]

The reaction in the system CuII/sacNa(H)/NCNR2 (sacNa(H) = sodium saccharinate (saccharin); R = Me, Et) results in the formation of the complexes [Cu(sac)2(NCNR2)(H2O)2] (R = Me 1, Et 2) instead of the expected products derived from the saccharin–cyanamide coupling. Complexes 1, 2, and hydrate 1·2H2O were characterized by IR, AAS (Cu%), TGA, and also by single-crystal X-ray diffraction for 1 and 1·2H2O. An integrated computational study of model structure 1 in the gas phase demonstrates that the Cu–Ncyanamide and Cu–Nsac coordination bonds exhibited a single bond character, polarized toward the N atom and almost purely electrostatic, with the calculated vertical total energies for the Cu–Ncyanamide and Cu–Nsac of 43.6 and 156.4 kcal/mol, respectively. These data confirmed that the copper(II) completely blocks the nucleophilic centers of ligands via coordination, thus preventing the saccharin–cyanamide coupling. [ABSTRACT FROM AUTHOR]

• N -Pyridylureas with an oxadiazole periphery has been achieved. • Obtained ureas have attractive hydrophilicity (cLogP < 3). • Simple, atom-economical, and scalable synthetic procedure. Pyridine- N -oxides bearing a pharmacophoric oxadiazole moiety could be C H functionalized via the acid-catalyzed reaction with dialkylcyanamides, providing access to hitherto undescribed pyridine-2-yl substituted ureas, which have potential as "lead-like" scaffolds for medicinal chemistry. Atom-economy, environmental friendliness (no halide-containing or toxic reagents), simple work-up, as well as scalability are the main advantages of the employed procedure. [ABSTRACT FROM AUTHOR]