N-HO and N-HCl supported 1D chains of heterobimetallic Cu II /Ni II -Sn IV cocrystals.

The Schiff base H2 L1 [N,N'-ethylenebis(3-methoxysalicylaldimine)] or H2 L2 [N,N'-ethylenebis(3-ethoxysalicylaldimine)] was reacted with MCl2 ·xH2 O and SnCl4 ·5H2 O to afford the supramolecular heterobimetallic systems (H2 ED)2+ ·2[ML]·[SnCl6 ]2- [M = Cu, L = L1 (1), L = L2 (2); M = Ni, L = L1 (3), L = L2 (4); ED = 1,2-ethylenediamine], whose structures were established by single crystal X-ray analyses. Each structure includes different entities, viz. a mononuclear [CuL]/[NiL] neutral complex (coformer), a hexachlorostannate dianion [SnCl6 ]2- , a 1,2-ethylenediammonium dication (H2 ED2+ ) and, only in 2 and 4, a methanol molecule. Based on the work of Grothe et al. (Cryst. Growth Des., 2016, 16, 3237-3243), compounds 1 and 3 are cocrystal salts, 2 and 4 are cocrystal salt solvates. The ionic pairs (H2 ED)2+ ·[SnCl6 ]2- in 1-4 are encapsulated by the Cu- or Ni-complexes, and stabilized by N-HO and one N-HCl bond interactions leading to infinite 1D chains. The antimicrobial studies of 1-4 against yeasts (C. albicans and S. cerevisiae) and Gram-positive (S. aureus and E. faecalis) and -negative bacteria (P. aeruginosa and E. coli) indicate that the Ni2 Sn systems (3 and 4) are more active than the analogous Cu2 Sn ones (1 and 2).