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Os térmitas (cupins) são insetos eusociais da ordem Isoptera que se subdividem em sete famílias. Neste trabalho analisamos a quiralidade do α- pineno presente na secreção defensiva do Constrictotermes cyphergaster (Isoptera, Termitidae, Nasutitermitinae), composto este que se mostrou majoritário entre os voláteis deste térmita. Juntamente com a verificação da quiralidade foi feito um estudo buscando correlacionar a produção de cada enantiômero, R(+)-α-pineno e S(-)-α-pineno, com dados edáfico-climáticos nas estações de seca e de chuva dos anos de 2002 e 2003. No tratamento estatístico dos dados foram usadas algumas técnicas estatísticas tais como análise de correspondência destendenciada, para prever o modelo; análise de variância, para comparação múltipla das médias; análise de redundância, para ter uma visualização da separação dos grupos e para correlacionar variáveis das matrizes resposta e ambiental. A análise destendenciada revelou que linear é o modelo mais apropriado. A análise de variância tanto para os dados originais quanto para os dados transformados mostraram que as médias não se diferenciam estatisticamente ao nível de 95 %, pois apresentam p>0,05. Pelas análises de redundância não foi possível a explicação da matriz resposta pelo ambiente, ao nível de 95 % de confiança. Houve uma produção enantiomérica de α-pineno por parte das populações de C. cyphergaster, que pode ser um fator importante para auxiliar em estudos quimiotaxonômicos desta espécie. Há maior produção do enantiômero (S), porém não foi possível correlacionar esta tendência com fatores edáfico-climáticos dentro de probabilidades estatisticamente significativas. A variação da composição enantiomérica pode estar relacionada a outros fatores que não os edáfico-climáticos, tais como: fatores ecológicos, genéticos e eusociais. Termites are eusocial insects of isoptera order that part in seven families. In this study we analyze the chirality of α-pinene in the defensive secretion that C. cyphergaster (Isoptera, Termitidae, Nasutitermitinae) this compound showed that among the majority of termite volatile. Along with checking the chirality was made a study seeking to correlate the production of each enantiomer, R(+)-α-pinene and S(-)-α-pinene, soil and climate data in dry and wet seasons of year 2002 and 2003. In the statistical data were used some statistical techniques such as Detrended Correspondence Analysis, to predict the model, Analysis of Variance for multiple comparison of means, and Redundancy Analysis to show a correlation matrix by another and that have a preview of the separation of groups. The DCA analysis showed that the model is linear. The analysis of variance for both the original data and for the transformed data showed that the averages do not differ statically at 95%, because they have p>0,05. The analysis of redundancy was not possible to explain the environment by the response matrix, in the 95% level of confidence. There was a production of enantiomeric α-pinene by the C. cyphergaster populations, which can be an important factor to assist in chemotaxonomic studies of these specimens. There is increased production of the (S) enantiomer, but it was not possible to correlate this trend with soil and climatic factors in statistically significant odds. The variation of the enantiomérica composition can be related to factors other than soil and climate, such as ecological factors, genetic, or eusocial.

The methoxylation of α-pinene was studied using heteropolyacids immobilized on silica as catalysts, at 60 °C, being the α-terpinyl methyl ether the main product. Tungstophosphoric acid (PW), molybdophosphoric acid (PMo), tungstosilicic acid (SiW) and molybdosilicic acid (SiMo) were immobilized on silica by sol–gel method. It was observed that the catalytic activity of the silica-supported heteropolyacids decreases in the series: PW2_S > SiW_S > PMo_S > SiMo_S. A series of PW immobilized on silica with different PW loading were prepared. It was observed that the catalytic activity increases with the amount of PW immobilized on silica. However, at high amount of PW on silica, a decrease of the catalytic activity was observed. Good values of selectivity to α-terpinyl methyl ether (about 60% near complete conversion) were obtained with all catalysts. Catalytic stability of the PW2_S was evaluated by performing consecutive batch runs with the same catalyst sample. After the third batch it was observed a stabilisation of the initial activity. A kinetic model was developed assuming that the α-pinene is consumed according to the parallel reaction network. It was observed that the kinetic model fits the experimental concentration data quite well.

The methoxylation of a-pinene was studied over sulfonic acid-functionalized mesoporous silica (MCM-41, PMO) at 60ºC. The support functionalization was achieved by the introduction of 3-(mercaptopropyl)trimethoxysilane onto the surface of these materials either by grafting or by co-condensation. The thiol groups were oxidized to SO3H by treatment with H2O2. All the catalysts were active in the studied reaction being the PMO-SO3H-g the best one. Good values of selectivity to a-terpinyl methyl ether were obtained with these catalysts. Catalytic stability of the PMO-SO3H-g was evaluated by performing consecutive batch runs with the same catalyst sample. After the third batch it was observed a stabilisation of the activity.