Destabilisation of a dual-synthon hydrogen bonding motif by packing effects and competing hydrogen bond donors

The chemistry and complexes of small cyano anions

“…The introduction of co-ligands that have a significant number of relatively strong hydrogen-bond donor groups, such as ethane-1,2-diamine and propane-1,3-diamine, disrupts the hydrogen bonding due to their competitive effects. 127 The Type 1 heterotape motif has also been observed between dinuclear complexes in the structure of [Cu(cdm)(2,2 0 -bipy)-(Cl)] 2 Á2MeOH. 127 Interestingly, when the bipyridine co-ligand is replaced by 1,10-phenanthroline a different complex is formed, despite the compound having a similar composition, [Cu(cdm)(1,10-phen)(Cl)] 2 Á2MeOH, and the heterotape motif is not present.…”

“…127 The Type 1 heterotape motif has also been observed between dinuclear complexes in the structure of [Cu(cdm)(2,2 0 -bipy)-(Cl)] 2 Á2MeOH. 127 Interestingly, when the bipyridine co-ligand is replaced by 1,10-phenanthroline a different complex is formed, despite the compound having a similar composition, [Cu(cdm)(1,10-phen)(Cl)] 2 Á2MeOH, and the heterotape motif is not present. The bipyridine complex contains two bridging chlorides and Z 1 (N) cdm ligands whereas the phenanthroline complex contains terminal chloride ligands and (N,O)-bridging cdm anions which remove the possibility of the heterotape forming.…”

Ammonium salts of carbamoyldicyanomethanide, C(CN)2(CONH2)−: Effects of hydrogen-bonding cations on anionic networks

“…Ag(cdm) was prepared by metathesis of K(cdm) [21][22][23][24] with Ag(NO 3 ) in water resulting in the immediate precipitation of pure Ag(cdm) which was collected by filtration and washed with MeOH.…”

“…20 Our recent work has examined the coordination chemistry and hydrogen-bonding motifs of the anionic species carbamoyldicyanomethanide, C(CN) 2 (CONH 2 ) À (cdm). [21][22][23][24][25] The cdm anion contains two nitrile arms that are able to either coordinate to metal ions or act as hydrogen-bond acceptors in addition to an amide functionality that provides both a hydrogen donor and acceptor group. In particular we have noticed the recurrence of a 'heterotape' motif that incorporates alternating hydrogenbond ring synthons between amide-amide and amide-nitrile groups (Scheme 1).…”

pH- and metal-dependent structural diversity from mononuclear to two-dimensional polymers based on a flexible tricarboxylate ligand

“…Flexible ones, however, can adopt different conformations to decrease the geometric constrain and steric hindrance, so may form unpredictable intriguing topologies and properties. In addition, various kinds of intermolecular weak interactions, such as O-H?O (N) hydrogen bonds, weak C-H?X (X¼O, N, p) and p?p stacking interactions, are always observed [28][29][30][31][32][33][34][35][36]. They can cooperate with metal-ligand coordination bonding, leading to interesting supramolecular architectures.…”