Phosphotungstic heteropoly acid as efficient heterogeneous catalyst for solvent-free isomerization of a-pinene and longifolene.

• Autor(a) principal: Rocha, Kelly Alessandra da Silva
• Data de Publicação: 2009
• Outros Autores: Robles Azocar, Patrícia Alejandra, Kozhevnikov, Ivan V., Gusevskaya, Elena Vitalievna
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFOP
• Texto Completo: http://www.repositorio.ufop.br/handle/123456789/5126; https://doi.org/10.1016/j.apcata.2008.10.005
• topic: Isomerization; Terpenes; Acid catalysis; Heteropoly acid

Silica-supported H3PW12O40 (PW), the strongest heteropoly acid in the Keggin series, is an efficient, environmentally friendly heterogeneous catalyst for the liquid-phase isomerization of a-pinene and longifolene into their more valuable isomers – camphene and isolongifolene, respectively, which are intermediates in the synthesis of expensive fragrances. The reactions occur under solvent-free conditions in the temperature range of 80–100 8C, with low catalyst loadings (0.15–5 wt%) and high turnover numbers (up to 6000 per proton). The catalyst can be easily recovered and reused. No PW leaching is observed in the reaction system.