Industrial & Engineering Chemistry Research, Vol.50, No.15, 8973-8982, 2011
La Complex@Fe-PILM Offering Resilient Option for Efficient and Green Processing toward Epoxidation of Cyclohexene
An overview focused on the synthesis, structural features, and catalytic applications of lanthanum salen complex heterogenized in iron pillared montmorillonite is described here. In this approach the pillaring species was introduced in the interlayers of montmorillonite by a simple cation-exchange mechanism. The material on subsequent calcination resulted in the formation of iron pillared montmorillonite. Consequently, lanthanum salen complex was intercalated into the porous structure of iron pillared montmorillonite. The prima facie evidence of pillaring and complex anchorage inside the pillared clay was established by various spectroscopic and analytical characterization techniques. The heterogeneous catalyst was identified to promote the cyclohexene epoxidation reaction very efficiently with tert-butylhydroperoxide (TBHP) as the oxidant, affording the desired product with a yield up to 95%. Again the reusability of the catalyst and its stability were investigated from its postcatalytic XRD and FT-IR analysis, which intimated that the catalyst could be reused up to four times without any reconditioning and loss of activity.