Molbank 2006, M468 |
Synthesis of
4-(4-(dimethylamino)phenyl)-5-acetyl-6-phenyl-3,4-dihydropyrimidin-2(1H)-thione
Fatma Aydin
17020, Canakkale-Turkey
e-mail: [email protected]
Received: September 2005 / Accepted:
Keywords: Biginelli
reaction, KF/Al2O3, Benzoxyacetone,
thiourea
4-(4-(dimethylamino)phenyl)-5-acetyl-6-phenyl-3,4-dihydropyrimidin-2(1H)-thione was prepared from benzoxyacetone (1) (1.62 g, 10 mmol), N,N-dimethylaniline (2) (1.21 g, 10 mmol) and thiourea (3) (1.140 g, 15 mmol) in dichloromethane (15 mL) as solvent using KF/Al2O3 (5 g) as a catalysis. The reaction mixture was heated under reflux conditions and stirred by using magnetic stirring until the one-pot addition was completed. The crude was filtered to remove residue on KF/Al2O3 and washed with DCM. The crude product was purified by column chromatography (silica gel, ethylacetate/n-hexane, 4:1, V/V as eluant) to give 4-(4-(dimethylamino)phenyl)-5-acetyl-6-phenyl-3,4-dihydropyrimidin-2(1H)-thione as pure yellow (4) (2.98 g, 85% yield).
Melting point: 118-120¡ãC
UV (EtOH; ¦Ëmax nm): 340
IR (KBr, cm-1):
3200 (N-H); 2951 (C-H Ar); 2853 (C-H); 2253; 1624; 1220
1H-NMR (400 MHz, CDCl3): ¦Ä= 3.48 (6H, s, N(CH3)2); 3.00 (1H, s, Benzyl-H); 2.48 (2H, brs, NH); 1.607 (3H, s, CH3CO); 6.8 (2H, d, Ar-H); 7.1-7.3 (5H, m, Ar-H); 7.8 (2H, d, Ar-H).
13C-NMR (100 MHz, CDCl3): ¦Ä= 190 (C=O); 184 (C=S); 175 (=C-N); 170 (-C-N); 154, 132, 129, 127, 125, 111, 40, 25
MS (m/z): 351 [M+]; 350; 308; 231.
Elemental Analysis: Calculated for C20H21N3OS: C, 68.41%; H, 6.08%; N, 11.89%; O, 4.58%; S, 9.17%. Found: C, 68.35%; H, 6.03%; N, 11.95%; O, 4.55%; S, 9.12%.
References
1. Kappe, C. O., Tetrahedron,
1993, 49, 6937-6963
2. Kappe, C. O., Molecules,
1998, 3, 1-9
3. Lin, H.; Ding, J.; Chen, X. and Zhang, Z. Molecules 2000,
5, 1240-1243
4. Salehi, P.;
Dabiri, M.; Zolfigol, M. A. and
Fard, M. A. B. Tetrahedron Letters 2003, 44, 2889-2891.
Sample Availability: Available from MDPI.
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