ether) (Found: C, 78.20; H, 5.50; N, 7.61. C24H20N2O2 requires
C, 78.24; H, 5.47; N, 7.60%); nmax(Nujol)/cm-1 1641 and 1606;
dH(300 MHz; CDCl3) 3.93 (3 H, s, OCH3), 5.89 (1 H, s, CH-
dH(300 MHz; CDCl3) 5.85 (1 H, s, CH-N C), 6.56 (1 H, s, C(4)H),
7.13 (2 H, t, J 8.7, Ar), 7.29–7.48 (6 H, m, Ph), 7.53–7.55 (2 H, m,
Ph), 7.74–7.77 (2 H, m, Ph), 7.88 (2 H, dd, J 2.7 and 8.7, Ar) and
8.50 (1 H, s, N CH-Ar); dC(62.5 MHz; CDCl3) 69.4, 98.4, 115.7
(d, J 22), 125.8, 127.1, 127.5, 127.7, 128.7, 128.9, 130.1, 130.5 (d,
J 9), 132.1, 140.9, 161.8, 164.6 (d, J 250, C–F), 166.4 and 170.0;
m/z: 356 (M+,100%).
N
C), 6.64 (1 H, s, C(4)H), 7.02 (2 H, d, J 9.0, Ar), 7.36–7.52 (6
H, m, Ph), 7.59–7.61 (2 H, m, Ph), 7.80–7.84 (2 H, m, Ph), 7.85
(2 H, d, J 9.0, Ar) and 8.53 (1 H, s, N CH-Ar); dC(62.5 MHz;
CDCl3) 55.4, 69.3, 98.5, 114.0, 125.8, 127.1, 127.5, 125.8, 127.8,
128.6, 128.8, 130.0, 130.2, 141.2, 162.1, 162.4, 166.7 and 169.9;
m/z: 368 (M+,100%).
N-(4-Chlorobenzylidene)-phenyl-(5-phenyl-isoxazol-3-yl)meth-
anamine 3h. (197 mg, 53%) mp 138–139 ◦C (from petroleum
ether) (Found: C, 74.13; H, 4.65; N, 7.53. C23H17ClN2O requires
C, 74.09; H, 4.60; N, 7.51%); nmax(Nujol)/cm-1 1645; dH(300 MHz;
CDCl3) 5.86 (1 H, s, CH-N C), 6.54 (1 H, s, C(4)H), 7.29–7.24 (8
H, m, Ph+Ar), 7.51–7.54 (2 H, m, Ph), 7.72–7.75 (2 H, m, Ph), 7.80
(2 H, d, J 8.4, Ar) and 8.49 (1 H, s, N CH-Ar); dC(62.5 MHz;
CDCl3) 69.4, 98.3, 125.7, 127.1, 127.3, 127.4, 127.6, 128.6, 128.8,
129.7, 130.0, 134.2, 137.2, 140.6, 161.8, 166.2 and 170.0; m/z: 374
[(M+2)+, 32.2%], 372 (M+,100).
N-(4-Methylbenzylidene)-phenyl-(5-phenyl-isoxazol-3-yl)meth-
anamine 3c. (268 mg, 76%) mp 172–173 ◦C (from petroleum
ether) (Found: C, 81.75; H, 5.70; N, 7.93. C24H20N2O requires C,
81.79; H, 5.72; N, 7.95%); nmax(Nujol)/cm-1 1641; dH(300 MHz;
CDCl3) 2.48 (3 H, s, CH3), 5.92 (1 H, s, CH-N C), 6.65 (1 H,
s, C(4)H), 7.24 (2 H, d, J 8.1, Ar), 7.37–7.50 (6H, m, Ph), 7.63–
7.60 (2 H, m, Ph), 7.81–7.86 (4 H, m, Ph+Ar) and 8.57 (1 H, s,
N
CH-Ar); dC(62.5 MHz; CDCl3) 21.5, 69.4, 98.5, 125.8, 127.2,
127.5, 127.6, 128.5, 128.6, 128.8, 129.3, 130.0, 133.3, 141.1, 141.6,
N-(4-Bromobenzylidene)-phenyl-(5-phenyl-1,2,4-isoxazol-3-yl)-
methanamine 3i. (266 mg, 64%) mp 156–157 ◦C (from petroleum
ether) (Found: C, 66.18; H, 4.14; N, 6.73. C23H17BrN2O requires
C, 66.20; H, 4.11; N, 6.71%); nmax(Nujol)/cm-1 1645; dH(300 MHz;
CDCl3) 5.86 (1 H, s, CH-N C), 6.54 (1 H, s, C(4)H), 7.29–7.45
(6 H, m, Ph), 7.51–7.59 (4 H, m, Ph+Ar), 7.73–7.76 (4 H, m,
Ph+Ar) and 8.48 (1 H, s, N CH-Ar); dC(62.5 MHz; CDCl3)
69.4, 98.3, 125.7 (overlapped signals), 127.0, 127.3, 127.7, 128.6,
128.7, 129.9, 130.0, 131.8, 134.6, 140.6, 161.9, 166.2 and 170.0;
m/z: 418 [(M+2)+, 97.5%], 416 (M+,100).
163.1, 166.6 and 169.9; m/z: 352 (M+,100%).
N-(3-Methylbenzylidene)-phenyl-(5-phenyl-isoxazol-3-yl)meth-
anamine 3d. (268 mg, 76%) mp 109–110 ◦C (from petroleum
ether) (Found: C, 81.76; H, 5.76; N, 7.97. C24H20N2O requires C,
81.79; H, 5.72; N, 7.95%); nmax(Nujol)/cm-1 1643; dH(300 MHz;
CDCl3) 2.49 (3 H, s, CH3), 5.93 (1 H, s, CH-N C), 6.65 (1 H,
s, C(4)H), 7.34–7.51 (8 H, m, Ph+Ar), 7.60–7.62 (2 H, m, Ph),
7.69–7.71 (1 H, m, Ar), 7.81–7.83 (3 H, m, Ph+Ar) and 8.58 (1
H, s, N CH-Ar); dC(62.5 MHz; CDCl3) 21.3, 69.5, 98.5, 125.8,
126.1, 127.2, 127.5, 127.6, 128.5, 128.6, 128.8 (overlapped signals),
130.0, 132.1, 135.8, 138.4, 141.0, 163.5, 166.5 and 170.0; m/z: 352
(M+,100%).
N-(4-Dimethylaminobenzylidene)-phenyl-(5-phenyl-isoxazol-3-
yl)methanamine 3j. (217 mg, 57%) mp 150–151 ◦C (from
petroleum ether) (Found: C, 78.74; H, 6.10; N, 11.00. C25H23N3O
requires C, 78.71; H, 6.08; N, 11.02%); nmax(Nujol)/cm-1 1645 and
1610; dH(300 MHz; CDCl3) 3.03 (6 H, s, 2 ¥ NCH3), 5.79 (1 H, s,
CH-N C), 6.58 (1 H, s, C(4)H), 6.71 (2 H, d, J 8.7, Ar), 7.28–7.45
(6 H, m, Ph), 7.52–7.55 (2 H, m, Ph), 7.73–7.74 (4 H, m, Ph+Ar)
and 8.39 (1 H, s, N CH-Ar); dC(62.5 MHz; CDCl3) 40.2, 69.2,
98.6, 111.5, 124.1, 125.8, 127.2, 127.3, 127.6, 128.5, 128.8, 129.9,
130.0, 141.6, 152.4, 162.9, 167.0 and 169.7; m/z: 381 (M+,100%).
N-(2-Methylbenzylidene)-phenyl-(5-phenyl-isoxazol-3-yl)meth-
anamine 3e. (282 mg, 80%) mp 95–96 ◦C (from petroleum ether)
(Found: C, 81.77; H, 5.76; N, 7.96. C24H20N2O requires C, 81.79;
H, 5.72; N, 7.95%); nmax(Nujol)/cm-1 1634 and 1600; dH(300 MHz;
CDCl3) 2.57 (3 H, s, CH3), 5.86 (1 H, s, CH-N C), 6.59 (1 H,
s, C(4)H), 7.20–7.47 (9 H, m, Ph+Ar), 7.54–7.57 (2 H, m, Ph),
7.73–7.77 (2 H, m, Ar), 8.05 (1 H, dd, J 1.2 and 7.5, Ar) and 8.85
(1 H, s, N CH-Ar); dC(62.5 MHz; CDCl3) 19.6, 70.2, 98.4, 125.8,
126.1, 127.1, 127.6 (overlapped signals), 128.4, 128.7, 128.8, 130.0,
130.7, 131,0, 133.7, 138.2, 141.1, 162.1, 166.7 and 170.0; m/z: 352
(M+,100%).
General procedure for BK rearrangement of imines 3: Synthesis of
imidazoles 4
To a solution of imine 3 (1 mmol) in DMF (5 ml) was added t-
BuOK (560 mg, 5 mmol). After 8 h of stirring at room temperature
under nitrogen, the reaction mixture was diluted with water and
extracted with diethyl ether (4 ¥ 50 mL). The combined organic
layers were dried over sodium sulfate and evaporated in vacuo. The
crude product was chromatographed giving 2-aryl-4(5)-phenacyl-
5(4)-phenyl-imidazoles 4a–j.
N-(4-Trifluoromethylbenzylidene)-phenyl-(5-phenyl-isoxazol-3-
yl)methanamine 3f. (276 mg, 68%) mp 75–76 ◦C (from petroleum
ether) (Found: C, 70.95; H, 4.27; N, 6.93. C24H17F3N2O requires
C, 70.93; H, 4.22; N, 6.89%); nmax(Nujol)/cm-1 1643 and 1610;
dH(300 MHz; CDCl3) 5.92 (1 H, s, CH-N C), 6.57 (1 H, s, C(4)H),
7.27–7.44 (6 H, m, Ph), 7.53–7.57 (2 H, m, Ph), 7.70 (2 H, d, J 8.2,
Ar), 7.74–7.84 (2 H, m, Ph), 7.99 (2 H, d, J 8.2, Ar) and 8.58 (1 H,
s, N CH-Ar); dC(62.5 MHz; CDCl3) 69.6, 98.4, 124.2 (q, J 207,
CF3), 125.6, 125.8, 127.4, 127.9, 128.8 (overlapped signals), 128.9,
130.2, 132.7 (q, J 32, C-CF3), 138.8, 140.5, 161.8, 166.2 and 170.2;
m/z: 406 (M+,100%).
4(5)-Phenacyl-2,5(4)-diphenyl-imidazole 4a. (287 mg, 85%) mp
79–80 ◦C (from petroleum ether) (Found: C, 81.66; H, 5.33;
N, 8.30. C23H18N2O requires C, 81.63; H, 5.36; N, 8.28%);
n
max(Nujol)/cm-1 1687; dH(300 MHz; CDCl3) 4.58 (2 H, s, CH2),
7.35–7.69 (11 H, m, Ph), 7.89–7.96 (2 H, m, Ph), 8.07–8.09 (2 H,
m, Ph) and 10.69 (1 H, br s, NH, exch. with D2O); dC(62.5 MHz;
CDCl3) 35.6, 124.8, 125.2, 126.9, 127.2, 127.3, 128.2, 128.5, 128.6,
128.7 overlapped signals, 130.0, 133.6, 136.3, 145.9, 152.4 and
197.4; m/z: 338 (M+,28%), 233 (100).
N-(4-Fluorobenzylidene)-phenyl-(5-phenyl-isoxazol-3-yl)meth-
anamine 3g. (249 mg, 70%) mp 152–153 ◦C (from petroleum
ether) (Found: C, 75.52; H, 4.83; N, 7.90. C23H17FN2O requires
C, 75.51; H, 4.81; N, 7.86%); nmax(Nujol)/cm-1 1643 and 1599;
494 | Org. Biomol. Chem., 2011, 9, 491–496
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The Royal Society of Chemistry 2011
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