Table 1: Ammonium acetate-mediated “on-water” synthesis of the Hantzsch 1,4-Dihydropyridines.

Entrya RCHO Time (min) Isolated yield of dihydropyridine (%)Observed M.p. ( C )Literature M.p. ( C )

1342738.table.001a 70 89 155 157 [10]
2342738.table.001b 75 91 139 140 [11]
3342738.table.001c 65 89 136 135–137 [22]
4342738.table.001d 75 80 229-230 230–232 [21]
5342738.table.001e 65 93 145 146 [10]
6342738.table.001f 65 96 125 126 [10]
7342738.table.001g 12092 163 163 [10]
8342738.table.001h 90 84 129 129 [11]
9342738.table.001i 9085162-163 163 [10]
10342738.table.001j 90 80 192-193 192–194 [46]
11342738.table.001k 70 89 145-146147 [10]
12342738.table.001l 80 86 142
13342738.table.001m 150b 70 Viscous oil
14342738.table.001n 180c 75 182 183 [36]
15342738.table.001o 120b 71 Viscous oil [10, 13]

aAldehyde : EAA : ammonium acetate = 1 : 2 : 1.3.
bReactions in water : ethanol = 1 : 1.
cReaction temperature = 30 C .