Microporous Polyacetylene Networks as Catalysts for beta-Pinene Oxide Rearrangement - Influence of Catalyst and Solvent Type
Abstract
Polyacetylene networks decorated with pendant ethynyl groups were tested as catalysts for isomerization of beta-pinene oxide (beta PO). The crucial effect of the amount of terminal ethynyl groups on the reaction course was confirmed, the final conversions of beta PO were 93 % resp. 55 % using PN-CAT p(TEB) resp. p(DEB) as a catalyst.
The reaction rates were also affected by the reaction temperature, the achieved conversions of beta PO were 100 % resp. 11 % (1 h) in the case of 100 degrees C resp. 50 degrees C. The basicity of used solvent influenced significantly the reaction course.
Using less basic solvents (toluene, 1,4-dioxane or acetonitrile) the conversions of beta PO about 70 % were achieved comparing to the more basic solvents (dimethyl sulfoxide, diphenyl sulfoxide or 2,4-dimethyl sulfolane), where almost total conversions of beta PO were obtained (4 h). PN-CATs could be possibly used as catalysts for this type of reaction achieving good yields of desired products.