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Abstracts: A green methodology was developed to obtain a large scope of Knoevenagel adducts with high yields (77-95%). The compounds were synthetized in 30 min, using aromatic aldehyde derivatives, malononitrile, water as a solvent, microwave irradiation as a heating source and in free-catalyst conditions. In a particular case, in the synthesis of the adduct derived from the α-methyl-trans-cinnamaldehyde, a [2+2] photochemical cycloaddition product was observed, a tetrasubstituted cyclobutane dimeric compound 3w’. Its complex structure was confirmed by X-ray diffraction (first time), nuclear magnetic resonance analysis and electronic structure calculations. Theoretical results suggest that the thermal decomposition of 3w’ back to 3w can occur by means of a biradical intermediate.

Neonicotinoids are a class of pesticides widely used in different phases of agricultural crops. Similar to other classes of pesticides, they can damage human and environmental health if overused, and can be resistent to degradation. This is especially relevant to insect health, pollination, and aquatic biodiversity. Nevertheless, application of pesticides is still crucial for food production and pest control, and should therefore be carefully monitored by the government to control or reduce neonicotinoid contamination reaching human and animal feed. Aware of this problem, studies have been carried out to reduce or eliminate neonicotinoid contamination from the environment. One example of a green protocol is bioremediation. This review discusses the most recent microbial biodegradation and bioremediation processes for neonicotinoids, which employ isolated microorganisms (bacteria and fungi), consortiums of microorganisms, and different types of soils, biobeds, and biomixtures.

Mosquitoes in the genus Aedes are responsible for the four important human disease viruses, such as, dengue, yellow fever, chikungunya and Zika. Although important advances have emerged in the development of alternative measures for mosquito control, chemical insecticides still remain a vital part of integrated control programs. In this sense, a set of benzylidenemalononitriles were synthetized in very good yields (99-71%), using only water and glycerol at temperature room. A comparative study of the larvicidal activity between benzylidenemalononitriles showed that the 2g (R= 4-Cl) compounds possess much better larvicidal activity (LC50 and LC90 of 9.42 and 15.02, respectively at 24h). Study of molecular docking was applied to identify the mode iteration of compound 2g with binding site at the enzyme acetylcholinesterase, the profile of interaction showed a score 48.9795, with five bonds in three different amino acids.

This study applied the use of marine-derived fungus Penicillium citrinum CBMAI 1186 in the stereoselective reduction of the C=C double bond of the prochiral (E)-2-methyl-3-phenylacrylaldehyde 1. The fungus immobilized on chitosan, obtained by multistep ultrasound-assisted deacetylation process (Ch-USAD), produced the (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 (c = 49%, 40% ee) isomer and (±)-2-methyl-3-phenylacrilic acid 4 (c = 35%); in contrast, immobilized mycelia on commercial chitosan (Ch-C) yielded the (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 (c = 48%, 10% ee) and (±)-2-methyl-3-phenylpropanal 1a (c = 41%). The reaction using free mycelia gave a 40% yield of (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 with 10% ee. These results showed that the crystallinity form and molecular weight of chitosan (Ch-C or Ch-USAD) used to immobilized mycelia of P. citrinum CBMAI 1186 influenced in the biotransformation of (E)-2-methyl-3-phenylacrylaldehyde 1. Therefore, marine-derived fungus P. citrinum CBMAI 1186 immobilized on chitosan can be a potential alternative in the studies of hydrogenation of the α,β-unsaturated carbon-carbon (α,β-C=C) double bond. Marine-derived fungus Penicillium citrinum CBMAI 1186 immobilized on chitosan in the stereoselective reduction of the C=C double bond of the prochiral (E)-2-methyl-3-phenylacrylaldehyde.

This work reports the green organic chemistry synthesis of E-2-cyano-3(furan-2-yl) acrylamide under microwave radiation (55 W), as well as the use of filamentous marine and terrestrial-derived fungi, in the first ene-reduction of 2-cyano-3-(furan-2-yl) acrylamide to (R)-2-cyano-3-(furan-2-yl)propanamide. The fungal strains screened included Penicillium citrinum CBMAI 1186, Trichoderma sp. CBMAI 932 and Aspergillus sydowii CBMAI 935, and the filamentous terrestrial fungi Aspergillus sp. FPZSP 146 and Aspergillus sp. FPZSP 152. A compound with an uncommon CN-bearing stereogenic center at the α-C position was obtained by enantioselective reactions mediated in the presence of the microorganisms yielding the (R)-2-cyano-3-(furan-2-yl) propanamide 3a. Its isolated yield and e.e. ranged from 86% to 98% and 39% to 99%, respectively. The absolute configuration of the biotransformation products was determined by time-dependent density functional theory (TD-DFT) calculations of electronic circular dichroism (ECD) spectra. Finally, the tautomerization of 2-cyano-3-(furan-2-yl) propanamide 3a to form an achiral ketenimine was observed and investigated in presence of protic solvents.

This paper describes an alternative route for the production of a high-surface-area ɳ-Al2O3/Nb2O5 catalyst synthesized from aluminum waste and niobium ammonium oxalate (NH4H2[NbO (C2O4)3]·3H2O). The effects of thermal treatment on the morphology and crystal structure were examined by X-ray powder diffraction (XPD), surface area measurements (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence, dynamic scanning calorimetry (DSC) and thermogravimetry (TG) measurement. The catalysts were evaluated in the glycerol dehydration reaction. Catalytic tests were carried out with reactants in gas-phase with a fixed-bed reactor at 300° and 400 °C.

This paper addresses the effects of the concentration of lipases, temperature and solvent on the enzymatic acetylation of primary amines. (±)-Heptan-2-amine 1, (±)-4-phenylbutan-2-amine 2, (±)-1,2,3,4-tetrahydronaphthalen-1-amine 3 and (±)-2-methylcyclohexan-1-amine 4 were acetylated using 11 lipases to obtain amides under orbital shaking and microwave radiation. Under microwave radiation the same amines were acetylated only using the CALB. (±)-Heptan-2-amine 1 was subjected to kinetic resolution, under orbital shaking for 7 h employing CALB and ethyl acetate as acylating agent, and converted into (R)-N- (heptan-2-yl)acetamide 5 (c = 42%, 88% ee

Aromatic and aliphatic nitriles are common intermediates in the industrial production of polyamides, pharmaceuticals, agrochemicals, dyes, pigments, and fine chemicals 1 . Moreover, in organic synthesis the nitrile group serves as an important starting material for various transformations into other functional groups, such as amines, aldehydes, ketones, heterocycles 2 . In this work a new way to synthesize benzonitriles is reported.