Three hexadentate Schiff base ligands were obtained by condensation of 3-ethoxy-2-hydroxybenzaldehyde and different diamines (1,2-diaminoethane, 1,2-diaminopropane, 1,2-diamino-2-metylpropane) to yield H2Ln (H2L1, H2L2 and H2L3, respectively). The ligands have been characterised by elemental analysis, IR, and 1H and 13C NMR spectroscopic techniques, mass spectrometry (ES) and X-ray diffraction.

Fluorescent benzo[a]phenoxazinium chlorides with dipropyl-, dioctyl- didecyl- and didodecyl-chains as the amino substituents of the 9-positions of the tetracyclic system were synthesised in moderate to good yields. All the compounds absorbed in the wavelength range of 638-641 nm and emitted at 673 or 676 nm with quantum yields of 0.17-0.19 in ethanol.

The silylcupration of allene has emerged as a useful tool for the synthesis of functionalized allylsilanes which have been used in the synthesis of different-sized carbocycles. We now described the preparation of allylsilane-allylcuprate intermediates by homologation reaction with iodomethylzinc iodide and their reaction with different electrophiles.

Thiocarbamic acid [(furan-2-yl) ethylidene] hydrazide has been synthesized by the reaction between 2-acetylfuran and thiosemicarbazide in 1:1 molar ratio under ball milling conditions. The title compound has been characterized by FT-IR and elemental analysis.

N-(3(5)-Aryl-1,2,4-triazol-5(3)-yl)-N'-carbethoxythioureas were prepared from ethoxycarbonyl isothiocyanate and 3(5)-amino-5(3)-aryl-1,2,4-triazoles. The annular prototropic tautomerism in the compounds was investigated by 1H NMR in DMSO solution. The tautomeric preferences depended on electronic properties of substituents on the phenyl ring and were well correlated with their Hammett constant values.

Oxidative deprotection of benzylic silyl ethers has been carried out using nitrogen dioxide gas to the corresponding aldehydes and ketones in quantitative yields.

Mono-Boc-protection of bispidine was achieved using equimolar amounts of TFA and Boc2O with iodine as catalyst.

2-(2-hydroxyphenyl)-1,3-bis[4-(2-hydroxyphenyl)-3-azabut-3-enyl]-1,3-imidazolidine (H3L) was obtained with high purity by Schiff's condensation between 5-bromosalicyaldehyde and triethylenetetramine. Its recrystallisation in methanol yields single crystals suitable for X-ray diffraction studies. H3L crystallises in the monoclinic system, space group P21/c, with a = 21.641(3) Å, b = 11.1217(14) Å, c = 11.4156(15) Å and β = 90.016 º.

The first hydroxilated series of coumarin-chalcone derivatives has been synthesize starting from the corresponding salicyl aldehyde and β-ketoester precursors by a Knoevenagel reaction in order to obtain the methoxy derivatives which have been further hydrolyzed with a Lewis acid.

Phase transfer catalysis (PTC) is an important modern synthetic method where reagents are located in different phases. Generally, it is transfer of inorganic reagent (base or nucleophile) from aqueous medium or solid phase to organic phase. Current catalysts for „classic" PTC are –onium salts (N, P, S), macrocyclic polyesters (crown-ethers), aza- -macrobicyclic ethers (cryptands), polyethylenglycols (PEGs) and their dimethylethers. Both in laboratory and industry, the most widely used catalysts are ammonium salts for their good price and availability. The other trend which is implementing within the frame of „Chemistry for sustainable development" are supported catalysts. Generally catalyst is bound on inorganic or organic polymer support and the system is insoluble in water and organic solvents as well. Supported catalyst can be easily separated from the reaction mixture and it can be reused again. Piperazine (A) as secondary cyclic 1,4-diamine offers two functional centers on its nitrogen atoms – one for preparation of quaternary catalytical place and second for immobilization on solid support, organic polymer.