Bulletin des societes chimiques belges vol:106 issue:9-10 pages:501-513
This work describes the qualitative determination of the non-volatile reaction products (condensables) in the alpha-pinene/OH/O-2/NO reaction. The study was carried out in a fast-flow reactor and the hydroxyl radicals were generated by the H+ NO2-reaction, Two collection systems have been checked: a liquid nitrogen trap and an active charcoal trap. It was found that the liquid nitrogen trap was the most suitable technique since heterogeneous reactions on the active charcoal surface lead to the formation of products not related to alpha-pinene/OH reaction. Both dichloromethane and methanol have been tried out as solvents but methanol has to be avoided since it forms a number of unwanted methanol-adducts during the extraction or analysis. The following condensables have been identified as genuine reaction products: pinonaldehyde. campholene aldehyde. trans-and cis-pinocamphone, pinol, trans-carveol, carvotaneacetone, trans-sobrerol and a ketoalcohol 5-(2-hydroxy-2-propyl)-2-methyl-2-cyclohexen-1-one.