J = 6.9 Hz, 3 H); 13C NMR (CDCl3, 100 MHz) d 149.3, 144.5,
128.2, 128.1, 127.6, 96.0, 77.0, 31.8, 29.8, 28.8, 22.0, 21.2, 13.8; IR
(neat, cm-1) 3363, 2956, 2928, 2865, 1620, 1592, 1486, 1458, 1442,
1367, 1285, 1222, 1175, 1104, 1060; MS (m/z): 344 (M+, 0.50), 327
((M-H2O)+, 22.04), 117 (100); HRMS calcd. for C15H21OI (M+):
344.0637, found: 344.0642.
6 H), 4.63 (q, J = 6.6 Hz, 1 H), 2.22-2.10 (m, 2 H), 1.77 (s, 1 H),
1.52-1.33 (m, 2 H), 1.30 (d, J = 6.6 Hz, 3 H), 1.18-1.03 (m, 4 H),
0.75 (t, J = 6.9 Hz, 3 H); 13C NMR (CDCl3, 75 MHz) d 142.6,
142.2, 141.5, 139.9, 128.8, 128.7, 128.1, 128.0, 126.4, 126.3, 68.3,
32.2, 30.2, 27.3, 22.0, 21.9, 13.8; IR (neat, cm-1) 3405, 3077, 3055,
3020, 2956, 2929, 2870, 1597, 1576, 1490, 1465, 1443, 1367, 1257,
1100, 1073, 1054, 1031, 1002; MS (m/z): 294 (M+, 2.19), 167 (100);
Elemental analysis calcd. for C21H26O: C, 85.67, H, 8.90; Found:
C, 85.66, H, 8.83.
Synthesis of 3-(n-pentyl)-4-phenylhepta-3(E),6-dien-2-ol (E-7a).
Following the procedure for the CuCl-mediated carbometallation
of propargylic alcohols with Grignard reagents described above,
the reaction was conducted using 1a (0.1499 g, 1.0 mmol),
CuCl (0.1041 g, 1.1 mmol, 1 equiv), 1.5 mL of toluene, and
a solution of n-C5H11MgBr in THF (6 mL, 1 M, 6 mmol,
6 equiv). After complete conversion of the starting material as
monitored by TLC, the reaction mixture was quenched by the
dropwise addition of a solution of allyl bromide (0.54 mL, d =
1.398 g/mL, 0.7549 g, 6.2 mmol, 6.2 equiv) in 2 mL of THF at
-40 ◦C, followed by warming up to rt naturally. The r◦esulting
mixture was treated with saturated aqueous NH4Cl at 0 C, and
extracted with Et2O (15 mL ¥ 3). The combined organic layer was
washed with 5% HCl (10 mL), sat. NaHCO3 (aq.) (10 mL), brine
(10 mL), and dried over anhydrous Na2SO4. After evaporation,
the NMR ratio was determined by using 1,3,5-trimethylbenzene
as the internal standard (35 mL, 0.25 mmol). Chromatography on
silica gel (eluent: petroleum ether/ethyl acetate = 20/1) of the
Synthesis of 5-methyl-4-(n-pentyl)-3-phenyl-2(5H)-furanone
(9a). To a Schlenk tube were added Pd(PPh3)4 (0.0242 g,
0.02 mmol, 5 mol%), Z-4a (0.1372 g, 0.40 mmol), Et3N (0.0828 g,
0.82 mmol, 2 equiv), and CH3CN (4 mL) at rt. This mixture was
degassed with CO using freeze–pump–thaw cycles and then heated
at 70 ◦C. After complete conversion of the starting material as
monitored by TLC, the reaction mixture was quenched by H2O
(5 mL) and extracted with Et2O (20 mL ¥ 3). The combined
organic layer was washed with 5% HCl (10 mL), sat. NaHCO3
(aq.) (10 mL), brine (10 mL), and dried over anhydrous Na2SO4.
Chromatography on silica gel (eluent: petroleum ether/ethyl
acetate = 20/1) of the crude product afforded 9a (0.0656 g, 67%).
1
Liquid. H NMR (300 MHz, CDCl3) d 7.47-7.32 (m, 5 H), 5.06
(q, J = 6.7 Hz, 1 H), 2.77-2.65 (m, 1 H), 2.42-2.30 (m, 1 H), 1.60-
1.40 (m, 5 H), 1.35-1.20 (m, 4 H), 0.91-0.82 (m, 3 H); 13C NMR
(CDCl3, 75 MHz) d 172.6, 166.1, 130.0, 128.8, 128.3, 128.2, 126.4,
77.9, 31.6, 27.4, 26.7, 22.1, 18.3, 13.8; IR (neat, cm-1) 2954, 2931,
2866, 1752, 1656, 1601, 1493, 1446, 1376, 1322, 1150, 1100, 1062;
MS (m/z): 244 (M+, 58.66), 91 (100); Elemental analysis calcd. for
C16H20O2: C, 78.65, H, 8.25; Found: C, 78.64, H, 8.26.
1
crude product afforded E-7a (0.2250 g, 85%): Liquid. H NMR
(300 MHz, CDCl3) d 7.34-7.27 (m, 2 H), 7.26-7.18 (m, 1 H), 7.11-
7.07 (m, 2 H), 5.82-5.67 (m, 1 H), 5.05-4.89 (m, 3 H), 3.15 (qdt,
J = 12.9, 6.3, and 1.5 Hz,2 H), 2.02-1.85 (m, 2 H), 1.59 (bs, 1 H),
1.38 (d, J = 6.6 Hz, 3 H), 1.35-1.19 (m, 2 H), 1.15-0.96 (m, 4 H),
0.74 (t, J = 7.1 Hz, 3 H); 13C NMR (CDCl3, 75 MHz) d 143.4,
140.3, 136.0, 135.5, 128.4, 127.9, 126.2, 115.2, 67.6, 38.7, 32.2,
30.3, 28.4, 22.1, 22.0, 13.9; IR (neat, cm-1) 3382, 3077, 3057, 3019,
2956, 2929, 2870, 1636, 1599, 1491, 1456, 1441, 1368, 1283, 1106,
1177, 1072, 1056; MS (m/z): 258 (M+, 1.22), 130 (100); HRMS
calcd. for C18H26ONa (M+ + Na): 281.1876, Found: 281.1870.
Acknowledgements
We greatly acknowledge financial support from the NSF of China
(20732005) and the Major State Basic Research Development
Program (2006CB806105). S. Ma is a Qiu Shi Adjunct Professor at
Zhejiang University. We thank Mr. Guofei Chen in this group for
allowing us to reproduce the results presented in entry 6 in Table 3,
entry 3 in Table 4, entry 4 in Table 5, and entry 2 in Table 6.
Synthesis of 3-(n-pentyl)-4,4-diphenyl-3-buten-2-ol (8a). Fol-
lowing the procedure for the CuCl-mediated carbometallation
of propargylic alcohols with Grignard reagents described above,
the reaction was conducted using 1a (0.1458 g, 1.0 mmol),
CuCl (0.0992 g, 1.0 mmol, 1 equiv), 1.5 mL of toluene, and a
solution of Grignard reagent in THF (6 equiv, 6 mmol). After
complete conversion of the starting material as monitored by
TLC, Pd(PPh3)4 (0.0237 g, 0.02 mmol, 2 mol%) and a solution
of PhI (1.2537 g, 6.2 mmol, 6 equiv) in THF (2 mL) were added
sequentially at rt. The resulting mixture was then heated at 80 ◦C
and monitored by TLC until the starting material disappeared.
This mixture was then quenched with saturated aqueous NH4Cl,
and extracted with Et2O (15 mL ¥ 3). The combined organic
layer was washed with 5% HCl (10 mL), sat. NaHCO3 (aq.)
(10 mL), brine (10 mL), and dried over anhydrous Na2SO4.
After evaporation, the NMR yield and ratio were determined
by using 1,3,5-trimethylbenzene as the internal standard (35 mL,
0.25 mmol). Chromatography on silica gel (eluent: petroleum
ether/ethyl acetate = 20/1 to 10/1) of the crude product afforded
8a (0.2204 g, 75%). According to 1H NMR analysis of crude
reaction mixture before separation, product 8a was formed in
80% yield together with 7% of protonolysis product. 8a: Liquid.
1H NMR (300 MHz, CDCl3) d 7.29-7.20 (m, 4 H), 7.19-7.10 (m,
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3262 | Org. Biomol. Chem., 2009, 7, 3258–3263
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