TRANSESTERIFICATION ON IMPRINTED SILICA

The transesterification reaction of ethyl phenylacetate to hexyl pheny lacetate on an ''imprinted'' silica catalyst of the type first reporte d by Heilmann and Maier is investigated. In the presence of sulfuric a cid co-catalysts, the data obtained here reveal that catalytic activit y can be due to phosphorous species leached into solution; no evidence for molecular recognition and catalysis from an imprinted site in the silica is observed. In the absence of co-catalysts, no conclusion reg arding the presence of an imprinted site in the silica can be ascertai ned because of the low level of activity relative to background autoca talysis.