Elizabeth L. Moyano

Catalytic and catalytic free process for cellulose conversion: fast pyrolysis and microwave induced pyrolysis studies

The catalytic and non-catalytic pyrolysis of microcrystalline cellulose and phosphoric acid pre-treated cellulose was investigated. The thermal processes were carried out applying two different methodologies: conventional fast pyrolysis and microwave-induced pyrolysis. For the catalytic experiments different catalysts were evaluated: CeO2, Nb2O5, SiO2, high surface area SiO2, Si-MCM-48 and Al-Fe-MCM-48. In all cases the liquid fraction was evaluated by quantifying the yields of anhydrosugars (mainly levoglucosan, levoglucosenone and 1,4:3,6-dianhydro-α-d-glucopyranose) and aromatic hydrocarbons. In the reaction of microcrystalline cellulose levoglucosan was the main product, while levoglucosenone was predominant in the pyrolysis of phosphoric acid pre-treated cellulose. Catalysts improved the fraction of bio-oil and the product distribution depended on the nature of catalytic materials as well as the starting cellulose. On the other hand, the microwave induced pyrolysis favored the formation of char at expenses of liquid fraction. In this case levoglucosenone and other anhydrosugars in conjunction with furan compounds were the main products.

Novel Synthesis of 2-thienylcarbonyl-cyclohexane-1,3-dione as Building Block for Indazolones and Isoxazolones

A new synthetic methodology using ultrasonic treatment was applied to the C-acylation of 1,3-cyclohexanedione with thiophene-2-carbonyl chloride to afford 3-hydroxy-2-(2-thienylcarbonyl)cyclohex-2-en-1-one (5). This compound was used as a building block to prepare different bicyclic systems: tetrahydro-4H-indazol-4-ones (7a–c and 9a,b,d), and 6,7-dihydrobenzisoxazole (11) by reaction with different hydrazines and hydroxylamine, respectively. Structural elucidation of all compounds was thoroughly achieved by NMR spectroscopy.

Flash vacuum pyrolysis (F.V.P.) of 1,2,4-benzotriazine derivatives

Flash vacuum pyrolysis of 3-methylsulfanyl-1,2,4-benzotriazine N-oxide, 3-methylsulfanyl-1,2,4-benzotriazine, and 3-phenyl-1,2,4-benzotriazine are described. The N-oxide derivative underwent deoxygenation between 500 and 600°C, whereas at higher temperatures both methylsulfanyl compounds, besides yielding the same products, also gave benzimidazole formed by an independent mechanism. Transformation of these derivatives between 600 and 750°C led to formation of a complex reaction mixture indicating the radical nature of the processes. The phenyl substituted derivative was studied between 575 and 650°C and afforded benzonitrile and traces of biphenylene.

Microwave Assisted Synthesis of ethyl-quinolon-4-one-3-carboxylates and Hydrolysis to quinolon-4-one-3-carboxylic Acids

Fil: Malvacio, Ivana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Investigaciones en Fisico-quimica de Cordoba. Universidad Nacional de Cordoba. Facultad de Ciencias Quimicas. Instituto de Investigaciones en Fisico-quimica de Cordoba; Argentina

A surface active benzodiazepine receptor ligand for potential probing membrane order of GABAA-receptor surroundings.

A conjugable analogue of the benzodiazepine 5-(2-hydroxiphenyl)-7-nitro-benzo[ e][1,4]diazepin-2(3 H)-one N 1-substituted with an aliphatic chain (CNZ acyl derivative, CAd) was synthesized. CAd inhibited FNZ binding to GABA A-R with an inhibition binding constant K i = 176 nM and expanded a model membrane packed up to 13 mN/m when penetrating from the aqueous phase. CAd exhibited surface activity with a collapse pressure pi = 18.8 mN/m and minimal molecular area A min = 49 A (2)/molecule at the closest molecular packing, resulting in full and nonideal mixing with a phospholipid in a monolayer up to a molar fraction x congruent with 0.1, decreasing its surface potential and contributing with a dipole that pointed its positive end toward the air and reoriented at the interface upon compression. These findings suggested that CAd could be stabilized at the membrane-water interface with its CNZ moiety stacked at the GABA A-R while its acyl chain can be inserted into the membrane depth.