Abstract
A new Schiff base ester 3-hydroxy-4-[(phenylimino)methyl]phenyl myristate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.
Schiff bases have received a considerable amount of attention from many researchers owing to their importance in exhibiting thermochromism and photochromism [1,2,3,4]. Aromatic Schiff bases possessing long alkyl chain have received much attention due to their possibility to exhibit liquid crystalline properties such as smectic and nematic phases [5,6,7,8,9].
Synthesis
4-Formyl-3-hydroxyphenyl tetradecanoate was previously prepared via Steglich esterification [10]. In a round-bottom flask, a mixture of the 4-formyl-3-hydroxyphenyl tetradecanoate (1.74 g, 5.0 mmol), aniline (0.47 g, 5.0 mmol) and absolute ethanol (50 mL) was refluxed with stirring for three hours. The reaction mixture was filtered and the solvent removed from the filtrate by evaporation. Recrystallization from absolute ethanol gave the title compound as yellow solid (1.14 g, 54%).
Melting point: 103.4 oC.
MS(EI): M+ (m/z) = 423 (4) [M]+, 213 (100).
IR (KBr, cm-1): 3435 (O-H), 2952, 2917, 2848 (C-H aliphatic); 1754 (C=O ester); 1629 (C=N); 1594, 1499 (C=C aromatic).
1H NMR (400 MHz, CDCl3): δ/ppm 0.90 (t, 3H, J = 6.9 Hz, CH3), 1.30-1.46 {m, 20H, CH3(CH2)10-}, 1.75 (q, 2H, J = 7.5 Hz, -CH2CH2COO-), 2.57 (t, 2H, J = 7.5 Hz, -CH2COO-), 6.71 (dd, 1H, J = 2.2, 8.4 Hz, Ar-H), 6.79 (d, 1H, J = 2.2 Hz, Ar-H), 7.28 (m, 3H, Ar-H), 7.39 (d, 1H, J = 8.4 Hz, Ar-H), 7.42 (m, 2H, Ar-H), 8.62 (s, 1H, CH=N), 13.60 (s, 1H, OH).
13C NMR (100 MHz, CDCl3): δ/ppm 172.1 (COO), 162.2 (CH=N), 163.0, 154.9, 148.6, 133.5, 129.8, 127.4, 121.6, 117.5, 113.3, 110.9 (aromatic carbons), 34.86 (-CH2COO-), 25.30 (-CH2CH2COO-), 32.34, 30.10, 30.07, 30.02, 29.88, 29.78, 29.67, 29.50, 23.11 (CH3(CH2)14-), 14.54 (CH3).
Elemental analysis: Calculated for C27H37NO3 C, 76.56%, H, 8.80%, N, 3.31%; Found: C, 76.45%, H, 8.87%, N, 3.44%.
Supplementary materials
Supplementary File 1Supplementary File 2Supplementary File 3Acknowledgements
The main author (S.T. Ha) would like to thank Universiti Tunku Abdul Rahman for the financial support and research facilities.
References and Notes
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