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Attempts to crystal engineermetallosupramolecularcomplexes from Cu(phen)2+building blocks and the prototypical,rod‐like, exo‐bidentate ligand 4,4′‐bipyridine (4,4′‐bipy) by layering techniques are described. Reactions of Cu(phen)2+(phen = 1,10‐phenanthroline) with 4,4′‐bipy in the presence of NO3–counterions yielded two distinct, discrete, dinuclear, Cisymmetric, dumbbell‐typecomplexes, [{Cu(NO3)2(phen)}2(4,4′‐bipy)] (1) and [{Cu(NO3)(phen)(H2O)}2(4,4′‐bipy)](NO3)2(2), depending upon the mixture of solvents used for crystallization. In compound 1, a mono‐ and a bidentate nitrato group coordinate to Cu2+, whereas in 2the monodentate nitrato groups are replaced by aqua ligands, which introduce additional hydrogen‐bond donor functionality to the molecule. The crystal structure of 1was determined by single‐crystal X‐ray analysis at 296 and 110 K. Upon cooling, a disorder‐order transition occurs, with retention of the space group symmetry. The crystal structure of 2at room temperature was reported previously [Z.‐X. Du, J.‐X. Li, Acta Cryst. 2007, E63, m2282]. We have redetermined the crystal structure of 2at 100 K. A phase transition is not observed for 2, but the low temperature single‐crystal structure determination is of significantly higher precision than the room temperature study. Both 1and 2are obtained phase‐pure, as proven by powder X‐ray diffraction of the bulk materials. Crystals of [Cu(phen)(CF3SO3)2(4,4′‐bipy)·0.5H2O]n(3), a one‐dimensional coordination polymer, were obtained from [Cu(CF3SO3)2(phen)(H2O)2] and 4,4′‐bipy. In 3, Cu(phen)2+corner units are joined by 4,4′‐bipy via the two vacant cissites to form polymeric zig‐zag chains, which are tightly packed in the crystal. Compounds 1–3were further studied by infrared spectroscopy.

Self‐assembly of Cd(phen)2+and Cu(phen)2+(phen = 1,10‐phenanthroline) building blocks with the bent ligand 4,4′‐dithiodipyridine (dtdp) has been investigated. Both building blocks serve as corner units with constrained cis‐geometry. The arched chain coordination polymer [{Cd(phen)(μ‐dtdp)(dtdp)(H2O)}(ClO4)2·2CH3OH·1.5H2O]n(1) crystallised from a mixture of Cd(ClO4)2·H2O, phen and dtdp in methanol. The reaction of [Cu(phen)(H2O)2](CF3SO3)2(2) with dtdp in an ethanol/water mixture yielded a chair‐like metallamacrocycle, [{Cu(phen)(CF3SO3)2}2(μ‐dtpd)2] (3). The crystal structure of the precursor complex 2is also reported.

Single crystal X‐ray diffraction analyses of LSn(OCH2CH2)2NR [1, R = Me, L = lone pair; 2, R = Me, L = W(CO)5; 3, R = t‐Bu, L = W(CO)5] reveal these compounds to be dimeric and cis‐configurated. The dimerization is realized by intramolecular O→Sn interactions to give four‐membered Sn2O2‐rings. In addition, there are intramolecular N→Sn interactions ranging in between 2.356(5) (2) and 2.549(4) Å (3).