PAPER
Arylimidazolines and Tetrahydropyrimidine Analogues
Yield: 140 mg (65%); mp 135–136 °C (hexanes–Et2O).
1479
13C NMR (CDCl3): d = 182.2, 154.6, 145.1, 139.7, 138.7, 132.5,
127.7, 127.8, 127.1, 118.9, 111.0, 59.6, 54.9, 40.9, 31.4, 28.9, 25.2.
1H NMR (CDCl3): d = 7.56–7.53 (m, 6 H), 6.98 (d, J = 8.7 Hz, 2 H),
3.98 (t, J = 4.8 Hz, 4 H), 3.85 (s, 3 H), 1.29 (s, 9 H).
ESI-MS: m/z (%) = 374 (100) [M + 1].
Anal. Calcd for C24H27N3O·1.25H2O: C, 72.79; H, 7.51; N, 10.61.
Found: C, 72.85; H, 7.14; N, 10.72.
13C NMR (CDCl3): d = 159.8, 159.4, 151.2, 142.1, 133.1, 130.7,
128.7, 128.1, 125.8, 114.2, 81.7, 55.3, 53.3, 47.8, 27.9.
ESI-MS: m/z (%) = 353.0 (70) [M + 1].
1-(tert-Butoxycarbonyl)-2-(4¢-cyanobiphenyl-4-yl)-5,5-dimeth-
yl-1,4,5,6-tetrahydropyrimidine (14)
Anal. Calcd for C21H24N2O3·0.2H2O: C, 70.84; H, 6.91; N, 7.87.
Found: C, 70.75; H, 6.89; N, 7.86.
By the above general procedure, the reaction between 9 (0.2 g, 0.6
mmol), Pd(PPh3)4 (29.4 mg, 0.02 mmol), (4-cyanophenyl)boronic
acid (0.1 g, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.4 mmol) yielded
white crystals after chromatographic purification (Et2O–hexanes,
2:1); yield: 0.2 g (85%). When 8 was used (0.2 g, 0.5 mmol) instead
of 9, 14 was isolated as white crystals; yield: 147 mg (70%).
1-(tert-Butoxycarbonyl)-2-(1,1¢:4¢,1¢¢-terphenyl-4-yl)-4,5-
dihydro-1H-imidazole (18)
By the above general procedure, the reaction between 1 (0.2 g, 0.6
mmol), Pd(PPh3)4 (28.2 mg, 0.02mmol), biphenyl-4-ylboronic acid
(140 mg, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.5 mmol) yielded
white crystals after chromatographic purification (Et2O–hexanes,
2:1).
Mp 181–182 °C (hexanes–Et2O).
1H NMR (CDCl3): d = 7.75 (m, 4 H), 7.63 (s, 4 H), 3.49 (d, J = 10.8
Hz, 4 H), 1.18 (s, 9 H), 1.06 (s, 6 H).
13C NMR (CDCl3): d = 153.4, 152.9, 145.0, 139.6, 139.5, 132.5,
127.6, 127.4, 126.6, 118.8, 110.9, 81.8, 59.7, 53.7, 31.0, 27.4, 24.7.
Yield: 150 mg (71%); mp 226.5–227.5 °C (hexanes–Et2O).
1H NMR (CDCl3): d = 7.72–7.60 (br m, 10 H), 7.47 (t, J = 7.2 Hz,
2 H), 7.37 (t, J = 7.2 Hz, 1 H), 4.00 (t, J = 4.2 Hz, 4 H), 1.30 (s, 9 H).
ESI-MS: m/z (%) = 390.4 (100) [M + 1].
13C NMR (CDCl3): d = 159.8, 151.2, 141.9, 140.6, 140.5, 139.4,
131.4, 128.8, 128.8, 127.5, 127.5, 127.4, 127.0, 126.1, 81.8, 53.4,
47.8, 28.9.
Anal. Calcd for C24H27N3O2: C, 74.01; H, 6.99; N, 10.79. Found: C,
73.76; H, 6.99; N, 10.66.
ESI-MS: m/z (%) = 348.1 (100) [M + 1].
1-Acetyl-2-(4¢-cyanobiphenyl-4-yl)-5,5-dimethyl-1,4,5,6-tetra-
hydropyrimidine (15)
By the above general procedure, the reaction between 5 (0.2 g, 0.6
mmol), Pd(PPh3)4 (29.4 mg, 0.02 mmol), (4-cyanophenyl)boronic
acid (0.1 g, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.4 mmol) yielded
semi-crystals after chromatographic purification (Et2O–hexanes,
2:1). (Deacetylation was detected by TLC.)
Anal. Calcd for C26H26N2O2: C, 78.36; H, 6.58; N, 7.03. Found: C,
78.40; H, 6.60; N, 6.91.
1-(tert-Butoxycarbonyl)-2-(4¢-cyanobiphenyl-4-yl)-4,5-dihydro-
1H-imidazole (19)
By the above general procedure, the reaction between 1 (1.0 g, 3.3
mmol), Pd(PPh3)4 (150 mg, 0.13 mmol), (4-cyanophenyl)boronic
acid (1.1 g, 3.6 mmol), and 2 M K2CO3 (3.6 mL, 7.8 mmol) yielded
white crystals after chromatographic purification (Et2O–hexanes,
3:1).
Yield: 30 mg (18%)
1H NMR (DMSO-d6): d = 7.93 (m, 4 H), 7.77 (d, J = 7.5 Hz, 2 H),
7.59 (d, J = 7.8 Hz, 2 H), 3.48 (s, 2 H), 3.38 (s, 2 H), 1.95 (s, 3 H),
0.95 (s, 6 H).
13C NMR (DMSO-d6): d = 170.8, 152.9, 143.9, 138.8, 138.2, 132.9,
127.6, 127.6, 126.8, 118.8, 110.7, 59.0, 53.3, 31.9, 24.8.
Yield: 830 mg (71%); mp 187–188 °C (hexanes–Et2O).
1H NMR (DMSO-d6): d = 7.96 (m, 4 H), 7.82 (d, J = 7.8 Hz, 2 H),
7.62 (d, J = 8.1 Hz, 2 H), 3.91 (t, J = 4.8 Hz, 4 H), 1.24 (s, 9 H).
ESI-MS: m/z (%) = 332.3 (100) [M + 1].
13C NMR (CDCl3): d = 159.4, 151.0, 144.9, 140.3, 132.7, 132.6,
129.0, 127.7, 126.4, 118.8, 111.2, 81.9, 53.4, 47.7, 27.9.
1-(tert-Butoxycarbonyl)-2-(4¢-fluorobiphenyl-4-yl)-4,5-
dihydro-1H-imidazole (16)
ESI-MS: m/z (%) = 348.1 (100) [M + 1].
By the above general procedure, the reaction between 1 (0.2 g, 0.6
mmol), Pd(PPh3)4 (28.2 mg, 0.02 mmol), (4-fluorophenyl)boronic
acid (120 mg, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.4 mmol) yield-
ed white crystals.
Anal. Calcd. for C21H21N3O2: C, 72.60; H, 6.09; N, 12.09. Found:
C, 72.35; H, 6.09; N, 11.98.
1-(tert-Butoxycarbonyl)-2-(4¢-formylbiphenyl-4-yl)-4,5-
dihydro-1H-imidazole (20)
Yield: 120 mg (58%); mp 134–135 °C (hexanes–Et2O).
By the above general procedure, the reaction between 1 (0.2 g, 0.6
mmol), Pd(PPh3)4 (28.2 mg, 0.02 mmol), (4-formylphenyl)boronic
acid (0.1 g, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.4 mmol) yielded
pale yellow crystals after chromatographic purification (Et2O–hex-
anes, 1:1).
1H NMR (CDCl3): d = 7.61–7.53 (br m, 6 H), 7.13 (t, J = 8.7 Hz, 2
H), 3.99 (t, J = 3.9 Hz, 4 H), 1.30 (s, 9 H).
13C NMR (CDCl3): d = 159.7, 151.1, 141.5, 136.7, 131.3, 128.8,
128.7, 126.1, 115.8, 115.5, 81.8, 53.3, 47.8, 27.9.
ESI-MS: m/z (%) = 341.3 (100) [M + 1].
Yield: 130 g (62%); mp 172–174 °C (hexanes–Et2O).
Anal. Calcd for C21H23FN2O2: C, 70.57; H, 6.22; N, 8.23. Found: C,
70.62; H, 6.15; N, 8.20.
1H NMR (DMSO-d6): d = 10.06 (s, 1 H), 8.00 (d, J = 8.4 Hz, 2 H),
7.93 (d, 8.1 Hz, 2 H), 7.79 (d, J = 8.4 Hz, 2 H), 7.59 (d, J = 8.1 Hz,
2 H), 3.88 (t, J = 4.8, 4 H), 1.23 (s, 9 H).
1-(tert-Butoxycarbonyl)-2-(4¢-methoxybiphenyl-4-yl)-4,5-
dihydro-1H-imidazole (17)
By the above general procedure, the reaction between 1 (0.2 g, 0.6
mmol), Pd(PPh3)4 (28.2 mg, 0.02 mmol), (4-methoxyphenyl)boron-
ic acid (110 mg, 0.7 mmol), and 2 M K2CO3 (0.7 mL, 1.4 mmol)
yielded white crystals after chromatographic purification (Et2O–
hexanes, 1:1).
13C NMR (DMSO-d6): d = 192.5, 158.0, 150.4, 145.0, 139.5, 135.2,
132.7, 130.0, 128.8, 127.2, 126.1, 80.8, 53.0, 47.3, 27.3.
ESI-MS: m/z (%) = 351.2 (100) [M + 1].
Anal. Calcd for C21H22N2O3·0.2H2O: C, 71.25; H, 6.38; N, 7.91.
Found: C, 71.31; H, 6.30; N, 7.83.
Synthesis 2007, No. 10, 1475–1480 © Thieme Stuttgart · New York