2154 Guguloth et al.
Asian J. Chem.
meter, mass spectra were recorded. Scanning electron micro-
scope (SEM) investigations were done on a Hitachi model
SEM-EDS S3700N scanning electron microscopy at a prag-
matic voltage of 15.0 KV. Nitrogen physisorption at 77 K was
used to determine BET surface area of the catalyst.
Preparation of catalyst: ZrOCl2·8H2O (50 g) was dissolved
in water and to obtain a white precipitate of zirconia, a 1 M
NH4OH solution was added by continuous stirring. The white
precipitate was washed with double distilled water till free
from all the chloride ions and thereafter dried in an oven at
393 K for a day.Ammonium paratungstate ((NH4)10H2(W2O7)6,
0.358 g) was dissolved in water until clear solution was obtained.
To this solution, 5 g of hydrated zirconia was added. The additi-
onal water was evaporated, dried the sample in an oven finally
calcined at 923 K. The pure ZrO2 sample was also prepared for
comparison.
General procedure:An organic acid (1 g), alcohol (excess)
and catalyst (0.1 g) mixture was heated in a round bottomed
flask. The completion of reaction is indicated by the total disapp-
earance of acid. Then after, the catalyst was separated by filtration
and reused. Sodium bicarbonate solution was added to the filtrate
and removed with ether. With anhydrous sodium sulphate, the
extract was dried and solvent was removed. Using ethyl acetate
and petroleum ether, the pure product was isolated by column
chromatography.
1H), 7.69-7.67 (dd, 2H, J = 8.4 Hz, J = 2.4 Hz); Mass (ES)
C10H12O4: m/z 196 [M]+, 197 [M+H]+.
Methyl 3,5-dimethoxybenzoate (3g): Solid, m.p.: 44-
46 ºC, IR (KBr, νmax, cm-1): 3408, 3017, 2958, 1717, 1597,
1350, 1208, 1159, 1102, 987, 845, 761, 674.1H NMR (CDCl3,
400 MHz): δ 3.82 (s, 6H), 3.90 (s, 3H), 6.65 (t, 1H, J = 2.4
Hz), 7.19 (d, 2H, J = 2.4 Hz); Mass (ES) C10H12O4: m/z 196
[M]+, 197 [M+H]+.
Methyl 4-bromobenzoate (3h): Solid, m.p.: 77-79 ºC,
IR (KBr, νmax, cm-1): 3420, 2951, 1714, 1590, 1439, 1288,
1277, 1115, 1010, 847, 758, 686.1H NMR (CDCl3, 400 MHz):
δ 3.91 (s, 3H), 7.59 (d, 2H, J = 8.8 Hz), 7.91 (d, 2H, J = 8.8
Hz); Mass (ES) C8H7O2Br: m/z 215 [M]+, 216 [M+H]+.
Methyl 4-fluorobenzoate (3i): Liquid, b.p.: 196-198 ºC,
IR (KBr, νmax, cm-1): 3079, 3000, 2954, 1728, 1602, 1508,
1436, 1154, 1112, 1015, 967, 855, 767, 607. 1H NMR (CDCl3,
400 MHz): δ 3.91 (s, 3H), 7.13 (3, 2H), 8.07 (m, 2H); Mass
(ES) C8H7O2F: m/z 154 [M]+, 155 [M+H]+.
Methyl 3-amino-4-methoxybenzoate (3j): Solid, m.p.:
84-86 ºC, IR (KBr, νmax, cm-1): 3431, 3354, 2953, 1698, 1688,
1593, 1517, 1445, 1182, 1117, 1025, 881, 763.1H NMR
(CDCl3, 400 MHz): δ 3.86(s, 3H), 3.87 (s, 2H), 3.90 (s, 3H),
6.80(d, 1H, J = 8.4 Hz), 7.38 (s, 1H), 7.48-7.45 (dd, 1H, J=8.8
Hz, J = 2.0 Hz); Mass (ES) C9H11O3: m/z 181 [M]+, 182 [M+H]+.
Methyl 3-chloro-4-methoxybenzoate (3k): Solid, m.p.:
95-96 ºC, IR (KBr, νmax, cm-1): 3385, 2957, 1703, 1601, 1504,
1430, 1240, 1061, 1018, 762.1H NMR (CDCl3, 400 MHz): δ
3.89 (s, 3H), 3.96 (s, 3H), 6.90 (d, 1H, J = 8.8 Hz), 7.95-7.92
(dd, 1H, J = 8.8 Hz, J = 2.0 Hz), 8.05 (s, 1H); Mass (ES)
C9H9O3Cl: m/z 200 [M]+, 201 [M+H]+.
Benzyl acetate (3a): Liquid, b.p.: 210-212 ºC, IR (KBr,
ν
max, cm-1): 3458, 3066, 3035, 2955, 1739, 1455, 1381, 1362,
1229, 1027, 750, 698. 1H NMR (CDCl3, 400 MHz): δ 2.10 (s,
3H), 5.10 (s, 2H), 7.37-7.32 (m, 5H); Mass (ES) C9H10O2: m/z
150 [M]+, 151 [M+H]+.
Benzyl benzoate (3b): Liquid, b.p.: 322-324 ºC, IR (KBr,
Methyl 4-methoxybenzoate (3l): Solid, m.p.: 48-50 ºC,
IR (KBr, νmax, cm-1): 3397, 2952, 2842, 1925, 1713, 1608,
1511, 1428, 1286, 1168, 1105, 964, 847, 770, 698. 1H NMR
(CDCl3, 400 MHz): δ 3.86 (s, 3H), 3.88 (s, 3H), 6.93 (d, 2H, J
= 9.2 Hz), 8.01 (d, 2H, J = 9.2 Hz); Mass (ES) C9H10O3: m/z
166 [M]+, 167 [M+H]+.
Methyl 4-nitrobenzoate (3m): Solid, m.p.: 96-98 ºC, IR
(KBr, νmax, cm-1): 3423, 3112, 3078, 1718, 1524, 1442, 1275,
1104, 721.1H NMR (CDCl3, 400 MHz): δ 3.98 (s, 3H), 8.23
(d, 2H, J = 8.8 Hz), 8.30 (d, 2H, J = 8.8 Hz); Mass (ES) C8H7O4:
m/z 181 [M]+, 182 [M+H]+.
Methyl 4-hydroxybenzoate (3n): Solid, m.p.: 127-128
ºC, IR (KBr, νmax, cm-1): 3314, 1680, 1607, 1588, 1162, 955,
850, 772, 698.1H NMR (CDCl3, 400 MHz): δ 3.89 (s, 3H),
6.02 (b, 1H), 6.89 (d, 2H, J = 8.8 Hz), 7.97 (d, 2H, J = 8.8 Hz);
Mass (ES) C8H8O3: m/z 152 [M]+, 153 [M+H]+.
ν
max, cm-1): 3420, 3090, 3065, 3034, 1716, 1451,1270, 1109,
1069, 1026, 735, 710.1H NMR (CDCl3, 400 MHz): δ 5.37 (s,
2H), 7.46-7.32 (m, 7H), 7.56(t, 1H, J=8.4 Hz), 8.08 (d, 2H,
J=8.4 Hz); Mass (ES) C14H12O2: m/z 212 [M]+, 213 [M+H]+.
Ethyl benzoate (3c): Liquid, b.p.: 213-214 ºC, IR (KBr,
ν
max, cm-1): 3063, 2982, 1719, 1276, 1108, 1070, 1027, 710.
1H NMR (CDCl3, 400 MHz): δ 1.39 (t, 3H, J = 7.2 Hz), 4.39
(q, 2H, J = 7.2 Hz), 7.45-7.41 (dd, 2H, J = 12 Hz, J = 1.6 Hz),
7.55 (t, 1H, J = 7.6 Hz), 8.06-8.03 (dd, 2H, J = 7.2 Hz, J = 1.6
Hz ); Mass (ES) C9H10O2: m/z 150 [M]+, 151 [M+H]+.
Ethyl 4-aminobenzoate (3d): Solid, m.p.: 88-90 ºC, IR
(KBr, νmax, cm-1): 3421, 3343, 2984, 1682, 1280, 846, 772.1H
NMR (CDCl3, 400 MHz): δ 1.37(t, 3H, J = 7.2 Hz), 4.07 (s,
2H), 4.34(q, 2H, J = 7.2 Hz), 6.64 (d, 2H, J = 8.4 Hz), 7.86 (d,
2H, J = 8.4 Hz); Mass (ES) C9H11O2: m/z 165 [M]+, 166 [M+H]+.
Isopropyl 3, 4-dihydroxybenzoate (3e): Liquid, b.p.:
358-360 ºC, IR (KBr, νmax, cm-1): 3458, 3316, 2984, 1676,
1609, 1443, 1296, 1238, 1102, 957, 768. 1H NMR (CDCl3,
400 MHz): δ 1.36(d, 6H, J = 6.4 Hz), 5.23 (m, 1H), 6.15 (bs,
1H), 6.46 (bs, 1H),6.92(d, 1H, J = 8.4 Hz), 7.55-77 (dd, 1H, J
= 6.8, 2 Hz), 7.71(d, 1H, J = 2 Hz); Mass (ES) C10H12O4: m/z
196 [M]+, 197 [M+H]+.
Ethyl acrylate (3o): Liquid, b.p.: 98-100 ºC, IR (KBr,
ν
max, cm-1): 2985, 1743, 1409, 1198, 1063, 809.1H NMR (CDCl3,
400 MHz): δ 1.32 (t, 3H, J = 7.2 Hz), 4.24 (q, 2H, J = 7.2 Hz),
5.83 (d, 1H, J = 9.2 Hz),6.15 (q, 1H, J = 10.4 Hz), 6.42 (d,
1H, J = 16 Hz); Mass (ES) C5H8O2: m/z 100 [M]+, 101 [M+H]+.
Butyl acrylate (3p): Liquid, b.p.: 145-146 ºC, IR (KBr,
1
ν
max, cm-1): 2962, 1727, 1408, 1192, 1067, 810. H NMR
Methyl 3,4-dimethoxybenzoate (3f): Solid, m.p.: 60-62
ºC, IR (KBr, νmax, cm-1): 3404, 3086, 3021, 2957, 1722, 1595,
1517, 1414, 1106, 1020, 869, 760.1H NMR (CDCl3, 400 MHz):
δ 3.89 (s, 3H), 3.94 (s, 6H), 6.90 (d, 1H, J = 8.4 Hz), 7.55 (s,
(CDCl3, 400 MHz): δ 0.96 (t, 3H, J = 7.2 Hz), 1.45 (m, 2H),
1.69 (m, 2H), 4.18 (t, 2H, J = 6.4 Hz), 5.82(d, 1H, J = 8.8 Hz),
6.13 (t, 1H, J = 6.4 Hz), 6.42 (d, 1H, J = 16 Hz); Mass (ES)
C7H12O2 m/z 128 [M]+, 129 [M+H]+.