Fatty Acid Copper(II) Carboxylates with Nicotinamide - Characterization and Fungicidal Activity. Crystal Structures of Two Heptanoate Forms and Nonanoate
Several new compounds of the composition Cu2(OOCCnH2n+1)4
(nia)2 (nia = nicotinamide; n = 6 to 11) were synthesized, characterized and tested for fungicidal activity. Crystal structure determinations revealed dinuclear structures of the copper(II) acetate hydrate type for compounds [Cu2(OOCC6H13)4(nia)2]-A (1A), [Cu2(OOCC6H13)4(nia)2]-B (1B) and [Cu2(OOCC8H17)4(nia)2] (3).
Other applied characterization methods indicate dimeric structures for ali synthesized compounds [μeff (298 K) = 1.43-1.50 BM; characteristic band in UV-Vis spectra in the region λ = 350-400 nm]. The same conclusion may also be deduced from the IR (Δ = νasym(COO-) - νsym(COO-) = 183-189 cm-1) and EPR spectra, though some differences were observed for heptanoate modification 1A, probably due to a different hydrogen bonding scheme. Screening for fungicidal activity against the wood-rotting fungus Trametes versicolor (L. ex Fr.) Pilat shows that the compounds dissolved in DMSO completely stop mycelium growth at a concentration of 1.0 × 10-3 mol L-1. Some of them (n = 8, 9, 10) show strong activity also in more diluted Solutions (1.0 × 10-4 mol L-1)
