21 resultados para Lewis Acid
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A multicomponent reaction of β-naphthol, dimethyl malonate, and aromatic aldehydes in the presence of NbCl5 as promoter is described. Under similar conditions, aromatic aldehydes with different substituents exhibited different behaviors than β-naphthol and dimethyl malonate. In these MCRs, 4-aryl-3,4-dihydrobenzo[f]coumarins are obtained as the major products (41–93%) and 14-aryl-14H-dibenzo[a,j]xanthenes as the minor products (1–38%).
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The objectives of this work were performing the biometric characterization of seed Chloroleucon foliosolum (Benth) G. P. (Lewis) from the municipality Ituaçu - BA, and analyze methods of scarification and temperature on germination. The seeds were characterized according to measurements of length, width and thickness, weight of thousand seeds, and water content. Were employed methods of scarification with sandpaper and sulfuric acid for 15 and 30 minutes, and not scarified seeds, combined with germination temperatures of 20, 25, 30 and 35 °C. Percentage and germination speed index, and percentage of primary root protrusion, abnormal seedlings, hard seeds and dead seeds were evaluated. The means of length, width and thickness was 6.03, 4.30 and 3.47 mm, respectively. The weight of a thousand seeds was 67.3 g with water content of 6.1%. Whereas the percentage germination with normal seedling, the method of scarification with sulfuric acid for 15 or 30 minutes combined to germination temperatures of 25 or 30 °C were effective in overcoming dormancy of Chloroleucon foliolosum.