For the first time, a series of catechol-containing Schiff bases, tetrasubstituted at the lower rim thiacalix[4]arene derivatives in three stereoisomeric forms, cone, partial cone, and 1,3-alternate, were synthesized. The structure of the obtained compounds was proved by modern physical methods, such as NMR, IR spectroscopy, and HRMS. Selective recognition (Kb difference by three orders of magnitude) of copper (II) cation in the series of d-metal cations (Cu2+, Ni2+, Co2+, Zn2+) was shown by UV-vis spectroscopy. Copper (II) ions are coordinated at the nitrogen atom of the imine group and the nearest oxygen atom of the catechol fragment in the thiacalixarene derivatives. High thermal stable organic-inorganic copper-based materials were obtained on the base of 1,3-alternate + Cu (II) complexes.
The ferrocenyl‐containing 3,5‐di‐tert‐butylcatechol Fc‐L‐CatH2 (2) was synthesized by the condensation of the precursor 6‐(hydrazonomethyl)‐3,5‐di‐tert‐butylcatechol 6‐(H2N–N=CH)CatH2 (1) with ferrocenecarboxaldehyde (L = –CH=N–N=CH–, Cat = 3,5‐di‐tert‐butylcatecholate, Fc = ferrocene). The exchange reaction between catechol 2 and Ph3SbBr2 in the presence of a base (Et3N) in toluene leads to the formation of the triphenylantimony(V) catecholate (Fc‐L‐Cat)SbPh3 (3) as the main product and the ionic bromotriphenylantimony(V) catecholate (Fc‐LH‐Cat)SbPh3Br (4) containing a hydraziniumylidene cation (LH = –CH=NH+–N=CH–) as the byproduct. The change of toluene to tetrahydrofuran (THF) results in the formation of 4 as the main product in nearly quantitative yield. The exchange reactions of catechol 2 with Ph2SnCl2 and SnCl4 give anionic catecholate complexes bridged with hydraziniumylidene cations even in the presence of excess base. Complexes (Fc‐LH‐Cat)SnPh2Cl (5), (Fc‐LH‐Cat)2SnPh2 (6), and (Fc‐LH‐Cat)2SnCl2 (7) were synthesized. The compounds obtained were characterized by IR spectroscopy, 1H and 13C NMR spectroscopy, elemental analysis, and cyclic voltammetry. The molecular structures of crystals of 5–7 were determined by X‐ray diffraction analysis. The formation of catecholates 4–7 with hydraziniumylidene cations is caused by intramolecular hydrogen bonding between the hydroxy and imine groups, which leads to proton transfer from the oxygen atom to the nitrogen atom of the hydrazine linker.
The world’s smallest moths in Lepidoptera (Insecta) and the complexity in making such a determination are examined and discussed. The forewing length and wingspan of 650 species were measured and the same data were retrieved from published papers to determine which species and family have the smallest moths in the world. The minimal recorded forewing length was found to be around 1.2–1.3 mm and the wingspan around 2.6–2.8 mm in two families, the Gracillariidae and Nepticulidae. Among Lepidoptera, the following species have the smallest moths globally: the European Johanssoniella acetosae (Stainton), the Peruvian Simplimorpha kailai Stonis & Diškus, the Mexican Stigmella maya Remeikis & Stonis, the Mediterranean S. diniensis (Klimesh), the Mediterranean Parafomoria liguricella (Klimesh) (Nepticulidae), the South East Asian Porphyrosela alternata Kumata, and the Central African P. desmodivora De Prins (Gracillariidae). Additionally, in the Nepticulidae, we provide a measurement update for Stigmella maya Remeikis & Stonis, one of the tiniest species with a forewing length of 1.3 mm and wingspan of 2.8 mm, and describe a new species, Stigmella incaica Diškus & Stonis, sp. nov., with a forewing length of 1.75 to 1.95 mm and a wingspan of 3.8 to 4.3 mm.
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