## 3 Results and Discussion
### Mizoroki-Heck Cross-Coupling Reaction by the Pd/C Catalyst  
The Pd/C catalyst for the Mizoroki-Heck cross-coupling reaction of 4-bromoanisol and acrylic acid in an aqueous medium was optimized as follows (Figure 7). In an air-tied screw-capped vial (10 mL), an x% Pd/C catalyst (5-15 mg), K\({}_{3}\)PO\({}_{4}\) (1.0-2.5 mmol), SDS (0.5-1.5 mmol) and water (4 mL) were charged with a small magnetic stir bar. Then, _p_-bromoanisol **1a** (1.0 mmol) was added, followed by acrylic acid (1.0 mmol). The reaction was left stirring at 70-100 \({}^{\circ}\)C for 2-20 h. The reaction was monitored by TLC chromatography and purified by acid-base purification techniques. The findings are reported in Table 1.  
The catalytic activity of a newly synthesized Pd/C nanocatalyst for a Mizoroki-Heck cross-coupling reaction in an aqueous medium was tested. The 4-bromoanisol and acrylic acid were taken as the standard substrates for the reaction optimization process (Figure 8). Our initial results are summarized in Table 1. Initially, the MH-C coupling reactions were tried with 10 mg of the **3%Pd/C** catalyst and 1 eq. of K\({}_{3}\)PO\({}_{4}\) in water (4 mL) at 100 \({}^{\circ}\)C for 10 h. Without the use of sodium dodecyl sulfate, no reaction took place (Table 1, entry 1). However, with the use of 0.5 eq. of sodium dodecyl sulfate (SDS), a 27% yield was observed (Table 1, entry 2). Then, the reaction was carried out using the same **3%Pd/C** catalyst in the presence of 1.0 eq. and 1.5 eq. of SDS while keeping the other parameters unchanged, but the yields remained almost the same (46% and 47%, respectively) (Table 1, entries 3 and 4). In order to increase the conversion, 1.5 eq. and 2.0 eq. of K\({}_{3}\)PO\({}_{4}\) were used in the reaction under the same reaction conditions, and 63% and 89% yields were found, respectively (Table 1, entries 5 and 6), which shows a sharp improvement in conversion. We then further tried to improve the yields using 15 mg of the catalyst and 2.5 eq. of K\({}_{3}\)PO\({}_{4}\) under similar conditions, but no further improvement was observed (**87%**, Table 1, entry 7). Similar reactions were tried using the **0.5%**, **1.0%** and **2% Pd/C** catalysts, and the respective yields were found to be 45%, 57% and 76% (Table 1, entries 8-10). We further tried to optimize \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Sl.** & **Catalyst** & **Wt. of Catalyst** & **K\({}_{3}\)PO\({}_{4}\)** & **SDS** & **Temp.** & **Time** & **Isolated** \\
**No.** & **Catalyst** & **K\({}_{3}\)PO\({}_{4}\)** & **SDS** & **(°C)** & **(h)** & **Yield** \\ \hline
1 & 3.0\% Pd/C & 10 mg & 1.0 eq. & - & 100 & 10 h & No reaction \\
2 & 3.0\% Pd/C & 10 mg & 1.0 eq. & 0.5 eq. & 100 & 10 h & 27\% \\
3 & 3.0\% Pd/C & 10 mg & 1.0 eq. & 1.0 eq. & 100 & 10 h & 46\% \\
4 & 3.0\% Pd/C & 10 mg & 1.0 eq. & 1.5 eq. & 100 & 10 h & 47\% \\
5 & 3.0\% Pd/C & 10 mg & 1.5 eq. & 1.0 eq. & 100 & 10 h & 63\% \\
6 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 10 h & 89\% \\
7 & 3.0\% Pd/C & 15 mg & 2.5 eq. & 1.0 eq. & 100 & 10 h & 87\% \\
8 & 0.5\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 10 h & 45\% \\
9 & 1.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 10 h & 57\% \\
10 & 2.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 10 h & 76\% \\
11 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 2 h & 17\% \\
12 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 5 h & 34\% \\
13 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 100 & 16 h & 86\% \\
14 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 90 & 20 h & 11\% \\
15 & 3.0\% Pd/C & 10 mg & 2.0 eq. & 1.0 eq. & 110 & 20 h & 83\% \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mizoroki–Heck reaction optimization of the Pd/C catalyst. Figure 7: Pd/C-catalyzed MH-C reaction of _p_-bromoanisol (1a) and acrylic acid. the reaction time and temperature, and it was observed that a reaction at 100 \({}^{\circ}\)C for 10 h gave the best results (Table 1, entries 11-15). It is evident from the above findings that the 3% Pd/C catalyst (10 mg) in the presence of 2 eq. of K3 PO4 and 1 eq.