Aminopyrimidine-Based Donor-Acceptor Chromophores
FTIR (KBr): ν = 3474, 3326, 2204, 1627, 1568 cm–1. UV/Vis
2952, 2213, 2200, 1581 cm–1. MS (EI): m/z = 586 [M]+, 521, 495,
334, 91. UV/Vis (CH3CN): λmax (ε) [nm]: 274.0 (72.3ϫ104), 465.0
(27.3ϫ104).
˜
(CH3CN): λmax (ε) [nm]: 282.0 (6.10 ϫ 104), 340.0 (5.87 ϫ 104),
417.0 (7.31ϫ104). MS (EI): m/z = 560 [M]+, 470.
2-Amino-4,6-dichloro-5-(1,2,2-tricyanoethyl)pyrimidine (5): 2-
Amino-4,6-dichloro-5-(2,2-dicyanovinyl)pyrimidine (3, 150 mg,
0.63 mmol) was suspended in ethanol (2 mL), KCN (42 mg,
0.65 mmol) in water (0.1 mL) was then added dropwise, and the
mixture was stirred at room temperature for 30 min. HCl (0.5 ,
2.4 mL) was added, and the solution was stirred overnight. A yel-
lowish solid was formed, filtered off, washed with hexane and
recrystallized from ethanol. (137.42 mg, 82%), m.p. 242–244 °C de-
comp. 1H NMR ([D6]DMSO, 400 MHz): δ = 5.72 (d, J = 10.1 Hz,
1 H), 5.94 (d, J = 10.1 Hz, 1 H), 8.07 (s, 2 H) ppm. 13C NMR
([D6]DMSO, 100 MHz): δ = 25.7, 31.6, 105.8, 110.9, 111.1, 114.2,
2-Amino-4,6-bis(diethylamino)-5H-pyrimidine (8): 2-Amino-4,6-
dichloropyrimidine (200 mg, 1.23 mmol) was dissolved in absolute
ethanol (10 mL). Diethylamine (1.0 mL) was added dropwise, the
solution was stirred and heated to reflux for 40 min, the solvent
was evaporated in vacuo, and the residues were purified by flash
chromatography (silica gel, CH2Cl2) (244.87 mg, 84 %), m.p.
1
191 °C. H NMR ([D6]DMSO, 400 MHz): δ = 1.18 (t, J = 7.6 Hz,
12 H), 2.87 (q, J = 7.6 Hz, 8 H), 8.80 (brs, 3 H) ppm. 13C NMR
([D6]DMSO, 100 MHz): δ = 12.7, 89.8, 158.7, 162.0, 162.5 ppm.
FTIR (KBr): ν = 3309, 3164, 2975, 1639, 1572 cm–1. UV/Vis
˜
(CH3CN): λmax (ε) [nm]: 289.0 (1.60ϫ104). MS (EI): m/z = 237
161.2 ppm. FTIR (KBr): ν = 3440, 3326, 2917, 2258, 1658, 1580
[M]+, 200, 185, 171, 157, 67.
˜
cm–1. MS (EI): m/z = 266 [M]+, 201.
2-Amino-4,6-dichloro-5-(tricyanovinyl)pyrimidine (6): 2-Amino-4,6-
dichloro-5-(1,2,2-tricyanoethyl)pyrimidine (5, 30 mg, 0.11 mmol),
NBS (78.3 mg, 0.44 mmol) and AIBN (5 mg) were dissolved in ace-
tonitrile (3 mL) and stirred at room temperature for 30 min. The
organic solvent was evaporated in vacuo to yield a yellowish solid,
which was washed with hexane and recrystallized from ethyl acetate
Acknowledgments
This work has been supported by COLCIENCIAS (Colombia), the
Universidad del Valle (Colombia), the Spanish Ministerio de Edu-
cación
y Ciencia (MEC) (grants CTQ2005-02609/BQU and
(26.53 mg, 91 %), m.p. 101–104 °C. 1H NMR ([D6]DMSO, CTQ2006-14987-C02-02/BQU), by the Comunidad de Madrid
400 MHz): δ = 7.30 (s, 2 H) ppm. 13C NMR ([D6]DMSO,
100 MHz): δ = 101.8, 108.5, 109.0, 106.3, 111.1, 158.7, 161.7–
(P-PPQ-000225-0505), by the Generalitat Valenciana, and by funds
of the Fondo Europeo de Desarrollo Regional (FEDER)
161.8 ppm. FTIR (KBr): ν = 3353, 3206, 2199, 1711, 1582 cm–1. (CTQ2006-14987-C02-02/BQU). M. A. H. would like to thank the
˜
MS (EI): m/z = 265 [M]+, 264, 229.
MEC for a “Ramón y Cajal” contract.
General Procedure for the Synthesis of Compounds 7a–d: The appro-
priate secondary amine (1.0 mL) was added dropwise to a solution
of 2-amino-4,6-dichloro-5-(tricyanovinyl)pyrimidine (6, 100 mg,
0.38 mmol) in absolute ethanol (10 mL). The solution was then
stirred and heated to reflux for 20 min. The organic solvent was
evaporated in vacuo, and the residue was purified by flash
chromatography (silica gel, CH2Cl2/MeOH, 20:1).
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2443.
2-Amino-4,6-bis(dimethylamino)-5-(tricyanovinyl)pyrimidine (7a):
72.87 mg, 68 %, m.p. 190–195 °C (dec.). 1H NMR ([D6]DMSO,
400 MHz): δ = 5.47 (s, 2 H), 3.25 (s, 12 H) ppm. 13C NMR ([D6]-
DMSO, 100 MHz): δ = 34.1, 98.5, 114.7, 162.1, 164.6 ppm. FTIR
(KBr): ν = 3419, 3330, 3210, 2925, 2196, 2177, 1595 cm–1. UV/Vis
˜
(CH3CN): λmax (ε) [nm]: 281.9 (15.0ϫ104), 454.0 (13.9ϫ104). MS
(EI): m/z = 282 [M]+, 242, 71.
2-Amino-4,6-bis(diethylamino)-5-(tricyanovinyl)pyrimidine (7b):
82.73 mg, 70 %, m.p. 210–211 °C dec. 1H NMR ([D6]DMSO,
400 MHz): δ = 8.48 (s, 2 H), 4.32 (q, J = 9.4 Hz, 8 H), 1.34 (t, J =
9.4 Hz, 12 H) ppm. 13C NMR ([D6]DMSO, 100 MHz): δ = 35.2,
49.7, 99.6, 115.9, 120.0, 123.2, 163.2, 165.7 ppm. FTIR (KBr): ν =
˜
3418, 3328, 3195, 2922, 2203, 2199, 2185, 1580 cm–1. UV/Vis
(CH3CN): λmax (ε) [nm]: 274.0 (19.9ϫ104), 459.9 (1.69ϫ104). MS
(EI): m/z = 311 [M]+, 296, 190.
2-Amino-4,6-bis(methylbenzylamino)-5-(tricyanovinyl)pyrimidine
(7c): 94 mg, 57 %, m.p. 200–203 °C dec. 1H NMR ([D6]DMSO,
400 MHz): δ = 8.17 (s, 2 H), 7.31 (m, 10 H), 4.85 (s, 4 H), 2.47 (s,
6 H) ppm. 13C NMR ([D6]DMSO, 100 MHz): δ = 55.9, 94.2, 130.5,
130.8, 131.7, 139.8, 169.9 ppm. FTIR (KBr): ν = 3421, 3324, 2930,
˜
2922, 2199, 2186, 1576 cm–1. UV/Vis (CH3CN): λmax (ε) [nm]: 273.9
(17.8ϫ104), 460.0 (7.24ϫ104). MS (EI): m/z = 434 [M]+, 419, 91.
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4084.
2-Amino-4,6-bis(dibenzylamino)-5-(tricyanovinyl)pyrimidine (7d):
155.88 mg, 70 %, m.p. 181–184 °C dec. 1H NMR ([D6]DMSO,
400 MHz): δ = 1.55 (s, 8 H), 4.53 (s, 2 H), 6.93 (m, 20 H) ppm. 13
C
NMR ([D6]DMSO, 100 MHz): δ = 46.6, 99.4, 128.3, 129.4, 129.6,
146.5, 158.2, 160.5, 163.8, 167.1 ppm. FTIR (KBr): ν = 3420, 3318,
˜
Eur. J. Org. Chem. 2008, 99–108
© 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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