Acylation of Ferrocene with Adamantoyl Chloride and Cinnamoyl Chloride

Liquid phase acylation of ferrocene with adamantoyl and cinnamoyl chloride was studied over different structural types of zeolites. The effect of the zeolite structure and acidity, and the influence of the reaction conditions on the ferrocene conversion and selectivity was investigated. The highest ferrocene conversions were achieved over zeolite Beta with Si/Al ratio 12.5 (cinnamoyl chloride 63.5%, adamantoyl chloride 45.9%). It was observed that with decreasing concentration of active sites in zeolite Beta the ferrocene conversion decreases. In addition, it was found that there is an optimum molar ratio of ferrocene to acylating agent, the ferrocene conversion increased with increasing temperature and amount of catalyst. The most important finding is that acylation of ferrocene with adamantoyl and cinnamoyl chloride leads exclusively to monoacylated products, most probably due to a deactivation of the cyclopentadiene rings after the attachment of the first acyl group.