Re duc tion of Propargyl Ethers to Al lyl ic Ethers
183.2066, found 183.0891.
J. Chin. Chem. Soc., Vol. 48, No. 5, 2001 875
phosphine (0.64 g, 2.46 mmol) to 1h (0.30 g, 1.23 mmol) at
-78 Cwaspurifiedviaflashcolumnchromatography(silica
gel, 10% ethyl acetate/hexanes) to give 2h (0.15 g, 0.59
mmol, 48%) as a col or less oil: IR (CH2Cl2) 3069, 3060, 2988,
2938, 1669, 1642, 1615, 1514, 1465, 1360, 1262, 1253, 1245,
1035 cm-1; 1H NMR (200 MHz, CDCl3) 7.27 (d,J = 8.4 Hz,
2H), 7.03-6.83 (m, 4H), 6.61 (dt, J = 15.6, 1.8 Hz, 1H), 6.33
(dt, J = 15.6, 1.8 Hz, 1H), 4.50 (s, 2H), 4.17 (dd, J = 4.2, 0.8
Hz, 2H), 3.79 (s, 3H), 1.90 (dd, J= 6.8, 1.0 Hz, 3H); 13C NMR
Trans-isomer
IR (CH2Cl2) 2991, 2982, 2254, 1722, 1664, 1304 cm-1;
1H NMR (400 MHz, CDCl3) 6.94 (dt, J = 15.6, 4.3 Hz, 1 )
6.10 (d, J = 15.6 Hz, 1H), 4.21 (m, 4H), 3.71 (d, J = 8.9 Hz,
2H), 2.64 (t, J = 8.9 Hz, 2H), 1.29 (t, J = 7.3 Hz, 3H); 13
C
NMR (100.4 MHz, CDCl3) 166.0, 142.8, 122.0, 117.5, 69.8,
65.4, 60.5, 18.9, 14.2; MS (EI) m/z (rel in ten sity) 183 (M+,
100), 153 (6), 138 (100), 129 (10), 110 (22); HRMS (EI) m/z
calcd for C9H13NO3 183.2066, found 183.0890.
(50.2 MHz, CDCl3)
189.05, 159.36, 143.59, 142.56,
130.56, 129.76, 129.28, 127.42, 113.79, 72.39, 68.63, 55.09,
18.18; MS (EI) m/z (relintensity) 246 (M+, 1), 203 (5), 173
(1), 147 (2), 135 (11), 121 (100), 110 (58), 95 (26), 69 (5);
(E)-5-(4-Methoxybenzyloxy)pent-3-en-2-one (2f)
The crude mix ture ob tained from ad di tion of triphenyl-
phosphine (2.39 g, 9.16 mmol) to 1f (1.00 g, 4.58 mmol) at
-78 Cwaspurifiedviaflashcolumnchromatography(silica
gel, 15% ethyl acetate/hexanes) to give 2f (0.47 g, 2.14
mmol, 47%)asacolorlessoil:IR(CH2Cl2) 3061, 2938, 1721,
HRMS (EI) m/z calcd for C H18O3 246.1256, found
246.1255.
15
(2E,5E,7E)-1-(4-Methoxybenzyloxy)nona-2,5,7-trien-4-one
(2i)
1
1678, 1633, 1613, 1514, 1422, 1360 cm-1; H NMR (200
The crude mix ture ob tained from ad di tion of triphenyl-
phosphine (2.52 g, 9.62 mmol) to 1i (1.30 g, 4.81 mmol) at
-78 Cwaspurifiedviaflashcolumnchromatography(silica
gel, 5% ethyl ac e tate/hex anes) to give2i (0.71 g, 2.60 mmol,
54%) as a col or less oil: IR (CH2Cl2) 3066, 3060, 3047, 2986,
2960, 2840, 1664, 1640, 1614, 1514, 1465, 1444, 1378, 1288,
1275, 1174, 1034, 1001 cm-1; 1H NMR (200 MHz, CDCl3)
7.29 (d, J = 8.4 Hz, 2H), 7.25-7.18 (m, 1H), 6.89 (d, J = 8.8
Hz, 2H), 6.90 (dt,J = 15.8, 4.2 Hz, 1H), 6.62 (dt,J = 15.8, 1.8
Hz, 1H), 6.33-6.18 (m, 3H), 4.51 (s, 2H), 4.19 (dd,J = 4.2, 2.0
Hz, 2H), 3.80 (s, 3H), 1.86 (d, J= 4.8 Hz, 3H);13C NMR (50.2
MHz, CDCl3) 189.31, 159.37, 143.93, 142.24, 140.66,
130.45, 129.79, 129.31, 127.98, 126.51, 113.82, 72.40,
68.67, 55.11, 18.63; MS (EI) m/z (relintensity) 273 (M+-1, 2),
260 (1), 176 (2), 147 (2), 136 (62), 121 (100), 108 (10), 67
(2); HRMS (EI) m/z calcd for C17H20O3 272.1412, found
272.1411.
MHz, CDCl3) 7.26 (d, J = 8.6 Hz, 2H), 6.88 (d, J = 8.8 Hz,
2H), 6.78 (dt, J = 16.0, 2.2 Hz, 1H), 6.31 (dt, J = 16.0, 1.8 Hz,
1H), 4.48 (s, 2H), 4.15 (dd, J = 1.8 Hz, 2H), 3.78 (s, 3H), 3.24
(s, 3H); 13C NMR (50.2 MHz, CDCl3) 198.01, 159.28,
143.07, 130.13, 129.56, 129.19, 113.70, 72.34, 68.26, 54.97,
26.90; MS (EI) m/z (rel in ten sity) 220 (M+, 5), 152 (9), 138
(21), 137 (93), 136 (21), 121 (100), 109 (22), 84 (24). Anal.
Calcd for C13H16O3: C, 70.89; H, 7.32. Found: C, 70.52; H,
7.29.
(E)-4-(4-Methoxybenzyloxy)-1-phenylbut-2-en-1-one (2g)
The crude mix ture ob tained from ad di tion of triphenyl-
phosphine (5.20 g, 19.87 mmol) to 1g (2.79 g, 9.94 mmol) at
-78 Cwaspurifiedviaflashcolumnchromatography(silica
gel,5%ethylacetate/hexanes)togive2g (2.22 g, 7.87 mmol,
79%): IR (CH2Cl2) 3070, 3047, 3007, 2986, 2959, 1674,
1613, 1580, 1448, 1360, 1327, 1271, 1252, 1209, 1114 cm-1;
1H NMR (200 MHz, CDCl3) 7.95 (d, J = 7.0 Hz, 2H),
7.57-7.43 (m, 3H), 7.31 (d, J= 8.4 Hz, 2H), 7.11 (dt, J = 14.0,
3.8 Hz, 2H), 6.91 (d, J = 8.8 Hz, 2H), 4.56 (s, 2H), 4.26 (dd, J
= 3.8, 1.6 Hz, 2H), 3.82 (s, 3H);13C NMR (50.2 MHz, CDCl3)
190.43, 159.45, 144.62, 137.71, 132.82, 129.82, 129.38,
128.62, 128.56, 124.93, 113.90, 72.56, 68.81, 55.17; MS (EI)
m/z (relintensity) 282 (M+, 1), 276 (2), 253 (2), 223 (1), 199
(1), 174 (3), 160 (5), 146 (40), 135 (17), 121 (100), 105 (33),
91 (7), 77 (18), 51 (4); HRMS (EI) m/z calcd for C18H18O3
282.1256, found 282.1258.
iso-Butyl 4-(4-methoxybenzyloxy)-2,3-dideuterobut-2-
enoate (8)
The crude mix ture ob tained from ad di tion of triphenyl-
phosphine (0.26 g, 1.0 mmol) to 1c (0.27 g, 1.0 mmol) fol-
lowed by quench ing the re ac tion mix ture with 0.6 mL of D2O
waspurifiedviaflashcolumnchromatography(silicagel,5%
ethylacetate/hexanes)togivecis-8 (0.11 g, 0.39 mmol, 39%)
and trans-8(0.06 g, 0.21 mmol, 22%) as col or less oils.
Cis-isomer
1H NMR (200 MHz, CDCl3) 7.27 (d, J = 8.8 Hz, 2H),
6.88 (d, J = 8.6 Hz, 2H), 4.61 (s, 2H), 4.48 (s, 2H), 3.89 (d,J =
6.6 Hz, 2H), 3.80 (s, 3H), 1.94-1.83 (m, 1H), 0.93 (d, J = 6.8
(2E,5E)-1-(4-Methoxybenzyloxy)hepta-2,5-dien-4-one (2h)
The crude mix ture ob tained from ad di tion of triphenyl-