In this work, we have explored the catalytic activity of Keggin-type heteropolyanions PMo12−nVnO40(3+n)− (n = 0, 1, 2, or 3) in the form of sodium salts in green oxidation routes of terpene alcohols with hydrogen peroxide.

In this work, Sn(II)-exchanged Keggin heteropoly acid salts were evaluated as solid catalysts in glycerol esterification reactions with acetic acid. All the Sn(II) heteropoly salts and their precursor Keggin acids were characterized by FT-IR/ATR, XRD, TG/DSC, BET, and EDS/SEM analyses. Among salts synthesized (i.e., Sn 3/2 PW 12 O 40 , Sn 2 SiW 12 O 40 , and Sn 3/2 PMo 12 O 40 ), Sn 3/2 PW 12 O 40 was the most active and selective catalyst toward glycerol esters. Effects of thermal treatment on the physical and chemical properties of Sn 3/2 PW 12 O 40 were investigated. The Sn 3/2 PW 12 O 40 -300 K catalyst was efficiently recovered and reused without a loss in activity. The influences of main reaction parameters such as reaction temperature, the stoichiometry of reactants, load, and thermal treatment temperature of the Sn 3/2 PW 12 O 40 catalyst were assessed. The simple workup of synthesis and the high activity and selectivity for glycerol esters in addition to the high efficiency during successive recycles are positive aspects of this catalyst.

In this work, an innovative and green oxidative process to convert renewable and abundant raw material to more value‐added fine chemicals was developed. Hydrogen peroxide, an environmentally benign oxidant, was used in Cs–exchanged lacunar Keggin heteropolyacid salts‐catalyzed oxidation reactions of the terpenic alcohols (i. e., nerol was the model molecule). The activity of most outstanding catalyst (Cs8SiW11O39) was compared with various catalysts. Epoxides and aldehydes, which are an attractive feedstock for fragrance and pharmaceutical industries were selectively obtained. Lacunar Keggin heteropolyacid salts containing cesium as the counter ion (i. e., Cs7PW11O39, Cs7PMo11O39 and Cs8SiW11O39) were easily synthesized and characterized by infrared spectroscopy, powdered X‐rays diffraction, X‐rays dispersive spectroscopy, scanning electronic microscopy, thermal analysis, porosimetry analyses, diameter and pores distribution. The influences of the main reaction variables such as catalyst concentration, the stoichiometry of the reactants and reaction temperature were evaluated. The reaction scope was successfully extended to the other terpenic alcohols. The Cs8SiW11O39 was the most active and selective lacunar salt. After five cycles of successive reuse, no loss of catalytic activity or selectivity was observed.

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