## 3 Results and Discussion
### \(\beta\)-Caryophyllene Oxidation  
#### 3.5.1 General Experimental Considerations  
The oxidation of \(\beta\)-caryophyllene was performed for 5 h with a POM/caryophyllene/oxidant molar ratio of 0.25/100/200 at 80 \({}^{\circ}\)C using TBHP as an oxidant and at 70 \({}^{\circ}\)C with H\({}_{2}\)O\({}_{2}\) as an oxidant. In some cases, toluene or ethyl acetate was added as a solvent with H\({}_{2}\)O\({}_{2}\). For the immobilized POMs, 0.1 g of a Merrifield-resin-supported catalyst (**MROrg@POMs**) was employed, with a 0.25 \(\times\) 10\({}^{-3}\)/100/200 POM/caryophyllene/oxidant molar ratio, under similar temperature conditions according to the nature of the oxidant. The reaction was monitored over time and quantified using GC-FID and using naphthalene as an internal standard. All relevant data have been collected in Table 3.  
The oxidation of \(\beta\)-caryophyllene leads primarily to the formation of \(\beta\)-caryophyllene oxide, a bicyclic sesquiterpene commonly found in various plants and essential oils [60,61]. This study will focus on this oxide.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Catalysts** & **Entry** & **T (\({}^{\circ}\)C)** & **Conditions** & \(\beta\)**-Caryo \({}^{\bf 1}\)** & **Conv (\%)** & **Oxide Yield (\%)** \\ \hline \multirow{2}{*}{**(BmIm)\({}_{\bf 3}\)PMo\({}_{\bf 12}\)O\({}_{\bf 40}\)**} & C1 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 98 & 26 \\  & C2 & 80 & TBHP\({}_{\bf aq}\) & 98 & 45 \\ \hline \multirow{2}{*}{**(BuPyr)\({}_{\bf 3}\)PMo\({}_{\bf 12}\)O\({}_{\bf 40}\)**} & C3 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 98 & 14 \\  & C4 & 80 & TBHP\({}_{\bf aq}\) & 98 & 24 \\ \hline \multirow{2}{*}{**(BmIm)\({}_{\bf 4}\)PMo\({}_{\bf 11}\)VO\({}_{\bf 40}\)**} & C5 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 99 & 40 \\  & C6 & 80 & H\({}_{2}\)O\({}_{\bf 2 aq}\) + EtOAc & 99 & 57 \\  & C7 & 80 & TBHP\({}_{\bf aq}\) & 98 & 64 \\  & C8 & 70 & TBHP\({}_{\bf dec}\) & 98 & 66 \\ \hline \multirow{2}{*}{**(BuPyr)\({}_{\bf 4}\)PMo\({}_{\bf 11}\)VO\({}_{\bf 40}\)**} & C9 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 99 & 15 \\  & C10 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) + EtOAc & 92 & 42 \\  & C11 & 80 & TBHP\({}_{\bf aq}\) & 99 & 31 \\  & C12 & 80 & TBHP\({}_{\bf dec}\) & 99 & 36 \\ \hline \multirow{2}{*}{Naked MR} & C13 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 5 & - \\  & C14 & 80 & TBHP\({}_{\bf aq}\) & 5 & - \\  & C15 & 80 & TBHP\({}_{\bf dec}\) & 11 & - \\ \hline \multirow{2}{*}{**MRImd@PMo\({}_{\bf 11}\)VO\({}_{\bf 40}\)**} & C16 & 70 & H\({}_{2}\)O\({}_{\bf 2 aq}\) & 94 & 36 \\  & C17 & 80 & TBHP\({}_{\bf aq}\) & 92 & 62 \\  & C18 & 80 & TBHP\({}_{\bf dec}\) & 94 & 62 \\ \hline \multirow{2}{*}{**MRImd@PMo\({}_{\bf 11}\)VO\({}_{\bf 40}\)**} & C19 & 80 & TBHP\({}_{\bf aq}\) & 62 & 20 \\ \cline{1-1}  & C20 & 71 & 21 \\ \hline \hline \end{tabular}  
* \({}^{1}\): \(\beta\)-caryophyllene. *: The reaction was conducted for 1 h with cat, then for the remaining 4 h after catalyst filtration. Catalysis conditions: For ionic salts of POMs: cat/sub/ox: 0.25/100/200, and at 80 \({}^{\circ}\)C with TBHP\({}_{\bf aq}\) and TBHP\({}_{\bf dec}\) and at 70 \({}^{\circ}\)C with H\({}_{2}\)O\({}_{\bf 2 aq}\) for 5 h. Toluene and ethyl acetate were added as solvents with H\({}_{2}\)O\({}_{\bf 2 aq}\) in some cases. For grafted POMs: 0.1 g of **MROrg@POMs** was used, in which cat/sub/ox: 0.25 \(\times\) 10\({}^{-3}\)/100/200, and at 80 \({}^{\circ}\)C with TBHP\({}_{\bf aq}\) and TBHP\({}_{\bf dec}\) and at 70 \({}^{\circ}\)C with H\({}_{2}\)O\({}_{\bf 2 aq}\) for 5 h.  
\end{table}
Table 3: Catalytic results of epoxidation of \(\beta\)-caryophyllene.