Ionic liquids (ILs) are considered one of the most promising green alternatives to molecular organic solvents. Nevertheless, before a widespread use of these compounds in a determined application, the knowledge of their ecotoxicity and biodegradability must be defined.

In this work the effect of addition of different doses of 1-butil-2,3-dimethylimidazolium trifluoromethanesulfonate, [C₄C₁C₁Im][OTf], on microbial activity of a soil under Pinus pinaster Aiton and on the seed germination of species of P. pinaster , Pinus sylvestris L., Pinus radiata D. Don and Eucalyptus globulus Labill were analyzed. Additionally, seed germination test were also applied to this IL after being subjected to heat treatment.

A microcalorimeter Thermal Activity Monitor (TAM-III) TA-Instruments was used to determine the influence of the addition of four doses (10 %, 25 %, 50 % and 75 %) on the microbial activity of a Galician soil, under P. pinaster. Methodology was widely exposed in previous works [1]. From the data obtained in these experiments, the calculation of microbial growth was performed [2].

Seed germination test of selected species were carried out for several doses of ILs (10 %, 1 %, 0.1 % and 0.01 %). The degradation treatment of the IL was carried out during 24 h in an oven at the temperature of 200 °C. Five replies with 25 seeds per Petri dish were incubated in a Phytotron (Climas AGP890) for every species and treatments. Seeds were maintained for 16 h under light at 24 ^°C and in the dark for 8 h at 16 ^°C during 45 days, when the germination was completed in all the species [3, 4].

Results of soil microbial activity and germination obtained for this IL were compared with the corresponding to other ILs, previously studied in our laboratory.  

Dose of 10 % inhibited totally the germination of the four species and dose of 1 % provoked an important reduction with regard to the control, both, for degraded and no-degraded IL. Nevertheless, in spite of all the doses showed differences on calorimetric parameters with regard to control; only the dose of 75 % does not show soil microbial response.

An efficient method for the synthesis of GO-chitosan bionanocomposite is demonstrated. Also, GO-chitosan is used as a green nanocatalyst in the synthesis of tetra-substituted imidazoles. This protocol has many advantages such as short reaction time, high yield, easy isolation of the catalyst and solvent-free conditions. We put upon Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyzes for the confirmation of the nanocomposite production.

A bis-amide bis-phenoxi N₂O₂  ligand was obtained from the 2:1 molar reaction of phenyl salicylate and the diamine, 1,4-Diaminobutane, to yield H₄L. The ligand has been characterised by elemental analysis, IR, and ¹H and ¹³C NMR spectroscopies, mass spectrometry (ES) and X ray diffraction spectroscopy.

A five-step synthesis of 4-(1-mesyloxyethyl)-6-methyl-5-tosyl-1,2,3,4-tetrahydropyrimidin-2-one via amidoalkylation has been developed. Reaction of this compound with C-, O-, S-, and N-nucleophiles led to the highly diastereoselective formation of polysubstituted 2,3,4,5-tetrahydro-1H-1,3-diazepin-2-ones as a result of ring expansion. The diastereoselectivity of the reaction depended on the nucleophile used and changed from cis to trans. The results obtained were explained by the formation of a bicyclic cyclopropane intermediate followed by cleavage of the zero bridge and stereoselective addition of the nucleophile to the resulting dihydro-1H-1,3-diazepin-2-one under kinetic control. The prepared cis-4-alkoxy-5-methyldiazepines reacted with alcohols under acidic conditions to give thermodynamically more stable trans-isomers.

The method uB3LYP/6-31g+(d) was used to simulate the reaction of photochemical oxidation of olefins such as ethylene with nitrobenzene and HNO₂ in the triplet state. It is found that photooxidation occurs in two stages. In a first step complex formation of the nitro compound with an olefin has place and in the second step its further degradation to nitrosocompound and ethylene oxide occurs. The energies of activation for each stage of the transformation were determined.