Table 3.
Comparison of the activity of agar-entrapped IL with those of other reported catalysts in the synthesis of 5-amino-7-(4-chlorophenyl)-7,8-dihydro[1,2,4]triazolo[4,3-a]pyrimidine (10b, entries1–6) and 7-amino-5-(4-chlorophenyl)-1,3-dimethyl-2,4- dioxo-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-6-carbonitrile (13b, entries 7–11) compared performance.
| Entry | Catalyst/Conditions [Ref.] | Time (min.) | Yield (%) |
|---|---|---|---|
| 1 | NaOH/Reflux-EtOH [35] | 30 | 82 |
| 2 | NaOH/US-H2O [35] | 60 | 88 |
| 3 | 1,8-Diazabicyclo[5.4.0]undec‑7-ene (DBU) / Reflux-EtOH [44] | 15 | 90 |
| 4 | [H2-DABCO][H2PO4]2/Solvent-free, 100 °C [36] | 40 | 95 |
| 5 | [H2-DABCO][ClO4]2/Solvent-free, 100 °C [36] | 50 | 96 |
| 6 | Agar entrapped [DABCO](SO3H)2Cl2 Solvent-free -100 °C | 35 | 98 |
| 7 | Nano-MgO/H2O,80 oC [41] | 15 | 90 |
| 8 | Triethanolamine/H2O,80 °C [45] | 120 | 92 |
| 9 | Al-HMS-20/EtOH-r.t. [46] | 720 | 92 |
| 10 | [H2-DABCO][ClO4]2/EtOH, 70 °C [36] | 50 | 95 |
| 11 | Agar-entrapped [DABCO](SO3H)2Cl2/EtOH, 70°C | 55 | 97 |