156
S. Jin et al. / Journal of Molecular Structure 1116 (2016) 155e164
O2N
O
O
S
NO2
OH
picric acid
N
OH
O2N
O
p-dimethylaminobenzaldehyde
p-toluenesulfonic acid
O2N
OH
O
HO
O
OH
HO
OH
O
O2N
OH
3,5-dinitrobenzoic acid
3,5-dihydroxy-benzoic acid
p-hydroxybenzoic acid
Scheme 1. The building blocks discussed in this paper.
dimethylaminobenzaldehyde:
(p-hydroxybenzoic
acid)
(3,5-
3282s(ns(NH)), 3055m, 2972m, 2924m, 2876m, 1692s, 1604m,
1578m, 1531m, 1486m, 1441m, 1400m, 1360m, 1318m, 1276m,
1234m, 1189m, 1068m, 1023m, 979w, 934m, 891w, 848m, 800m,
757m, 714m, 666w, 631m, 618w.
[(L)/(phba)]
(3),
p-dimethylaminobenzaldehyde:
dihydroxybenzoic acid)2: (H2O)2 [(L)/(dhba)2/(H2O)2] (4), and
p-dimethylaminobenzaldehyde: (3,5-dinitrobenzoic acid)
[(L)/(Hdba), Hdba ¼ 3,5-dinitrobenzoic acid] (5), respectively
(Scheme 2).
2.2.3. p-dimethylaminobenzaldehyde: (p-hydroxybenzoic acid)
[(L)·(phba)] (3)
2. Experimental section
p-dimethylaminobenzaldehyde (14.9 mg, 0.1 mmol) was dis-
solved in 2 mL methanol. To this solution was added p-hydrox-
ybenzoic acid (14.9 mg, 0.1 mmol) in 8 mL ethanol. Colorless block
crystals were afforded after several days by slow evaporation of the
solvent (yield: 22 mg, 76.57%, based on L). mp 154e156 ꢁC.
Elemental analysis: Calc. for C16H17NO4 (287.31): C, 66.83; H, 5.92;
N, 4.87. Found: C, 66.78; H, 5.89; N, 4.84. Infrared spectrum (KBr
2.1. Materials and methods
The chemicals and solvents used in this work were of analytical
grade and available commercially and were used without further
purification. The C, H, N, and S microanalysis were carried out with
a Carlo Erba 1106 elemental analyzer. The FT-IR spectra were
recorded from KBr pellets in range 4000e400 cmꢀ1 on a Mattson
Alpha-Centauri spectrometer. Melting points of new compounds
were recorded on an XT-4 thermal apparatus without correction.
disc, cmꢀ1): 3671w(br,
2879m, 1687s, 1638s(
1424m, 1378m, 1333m, 1290s(
n
(OH)), 3129m, 3046m, 2991m, 2916m,
(C]O)), 1595m, 1550m, 1508m, 1465m,
(CeO)), 1247m, 1203m, 1159m,
n
n
1117m, 1076m, 1033m, 990m, 948m, 905m, 862m, 820m, 779m,
732m, 691m, 646m, 622m, 600m.
2.2. Preparation of supramolecular compounds
2.2.4. p-dimethylaminobenzaldehyde: (3,5-dihydroxybenzoic
acid)2: (H2O)2 [(L)·(dhba)2·(H2O)2] (4)
2.2.1. p-dimethylaminobenzaldehyde: (picric acid) [(HLþ)·(picꢀ)]
(1)
p-dimethylaminobenzaldehyde (14.9 mg, 0.1 mmol) was dis-
solved in 2 mL methanol. To this solution was added 3,5-
dihydroxybenzoic acid (15.4 mg, 0.1 mmol) in 10 mL ethanol.
Colorless prisms were afforded after several days of slow evapo-
ration of the solvent, yield: 34 mg, 68.90%. mp 140e142 ꢁC.
Elemental analysis: Calc. for C23H27NO11 (493.46): C, 55.93; H, 5.47;
N, 2.84. Found: C, 55.88; H, 5.45; N, 2.79. Infrared spectrum (KBr
p-dimethylaminobenzaldehyde (14.9 mg, 0.1 mmol) was dis-
solved in 2 mL methanol. To this solution was added picric acid
(22.9 mg, 0.1 mmol) in 20 mL methanol. Yellow block crystals were
afforded after several days by slow evaporation of the solvent
(yield: 28.0 mg, 74.02%, based on L). mp 91e92 ꢁC. Elemental
analysis: Calc. for C15H14N4O8(378.30): C, 47.58; H, 3.70; N, 14.80.
Found: C, 47.54; H, 3.68; N, 14.76. Infrared spectrum (KBr disc,
cmꢀ1): 3377s(nas(NH)), 3269s(ns(NH)), 3122m, 3071m, 2981m,
2968m, 2800m, 1753s, 1627m, 1584m, 1533s(nas(NO2)), 1488m,
1445m, 1402m, 1361m, 1318s(nas(NO2)), 1272m, 1227m, 1177m,
1133m, 1091m, 1048m, 1003m, 955w, 912m, 867w, 824m, 775w,
730m, 684w, 643m, 626w, 602m.
disc, cmꢀ1): 3630s(
1599m, 1547m, 1501m, 1459m, 1418m, 1376m, 1338m,
1296s( (CeO)), 1253m, 1210m, 1168m, 1124m, 1082m, 1039m,
n(OH)), 2963s, 2855m, 1706s, 1652s(n(C]O)),
n
994m, 952m, 899m, 855m, 813m, 768m, 725m, 684m, 652m, 617m.
2.2.5. p-dimethylaminobenzaldehyde: (3,5-dinitrobenzoic acid)
[(L)·(Hdba), Hdba ¼ 3,5-dinitrobenzoic acid] (5)
2.2.2. p-dimethylaminobenzaldehyde: (p-toluenesulfonic acid):
(H2O) [(HLþ)·(tsaꢀ)·H2O] (2)
p-dimethylaminobenzaldehyde (14.9 mg, 0.1 mmol) was dis-
solved in 2 mL methanol. To this solution was added 3,5-
dinitrobenzoic acid (21.2 mg, 0.1 mmol) in 10 mL ethanol. Color-
less block crystals were afforded after several days by slow evap-
oration of the solvent (yield: 26 mg, 71.96%, based on L). mp
124e125 ꢁC. Elemental analysis: Calc. for C16H15N3O7 (361.31): C,
53.14; H, 4.15; N, 11.62. Found: C, 53.11; H, 4.09; N, 11.58. Infrared
p-dimethylaminobenzaldehyde (14.9 mg, 0.1 mmol) was dis-
solved in 2 mL methanol. To this solution was added p-toluene-
sulfonic acid (19.0 mg, 0.1 mmol) in 6 mL ethanol. Colorless block
crystals were afforded after several days by slow evaporation of the
solvent (yield: 27.0 mg, 79.55%, based on L). mp 82e83 ꢁC.
Elemental analysis: Calc. for C16H21NO5S (339.40): C, 56.57; H, 6.19;
N, 4.12; S, 9.43. Found: C, 56.54; H, 6.15; N, 4.08; S, 9.41. Infrared
spectrum (KBr disc, cmꢀ1): 3678
n(OH), 3112m, 3064m, 2960m,
2881m, 1722s, 1661(nas(C]O)), 1616m, 1602m, 1526s(nas(NO2)),
1458m, 1415m, 1373m, 1332s(ns(NO2)), 1289(ns(CeO)), 1245m,
spectrum (KBr disc, cmꢀ1): 3712w(br,
n(OH)), 3391s(nas(NH)),