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Can. J. Chem. Vol. 82, 2004
dropwise by syringe and the mixture was allowed to stir at
−78 °C for 1.5 h. Following this period, the reaction was
placed in a 0 °C bath for 30 min or until nitrogen evolution
ceased. After recooling to –78 °C, (E)-5-(3-methoxyphenyl)-
2-methyl-2-pentenal (9b) (0.245 g, 1.28 mmol) was added
via cannula in a solution with THF (2 mL). The reaction was
monitored by TLC and quenched with satd. NH4Cl (10 mL)
upon consumption of aldehyde. The crude product was ex-
tracted with Et2O (3 × 10 mL), dried (MgSO4), concen-
trated, and purified by radial chromatography (silica gel,
2 mm plate, EtOAc/Hex (1:10 to 1:4)) to yield 0.165 g
(47%) (E,E′)-8-(3-methoxyphenyl)-3-ethyl-5-methyl-2,5-octadien-
4-ol (12c) as a clear, pale yellow oil. Rf 0.64 (EtOAc/Hex,
1:1). IR (thin film, cm–1): 3453 (br), 2961, 2929, 2871,
(CDCl3) δ: 200.9, 159.9, 143.2, 140.2, 140.0, 138.4, 136.6,
129.6, 121.0, 114.5, 111.4, 55.4, 35.1, 30.4, 25.9, 24.5, 22.3,
21.9, 13.2.
(E)-7-(3,4-Methylenedioxyphenyl)-2,4-dimethyl-1,4-hepta-
dien-3-one (11e)
The general procedures described for 11a were followed
using 9c in place of 9a.
(E)-7-(3,4-Methylenedioxyphenyl)-2,4-dimethyl-1,4-hepta-
1
dien-3-ol (12e): colorless oil. Rf 0.27 (EtOAc/Hex, 1:4). H
NMR (CDCl3) δ: 6.72 (d, J = 7.9 Hz, 1H), 6.68 (d, J =
1.7 Hz, 1H), 6.63 (dd, J = 7.9, 1.7 Hz, 1H), 5.91 (s, 2H),
5.52 (tqd, J = 7.1, 1.2, 1.2 Hz, 1H), 5.05 (br s, 1H), 4.91
(br s, 1H), 4.39 (br s, 1H), 2.61 (t, J = 7.5 Hz, 2H), 2.34 (dt,
J = 7.5, 7.5 Hz, 2H), 1.58 (br s, 1H) overlapping with 1.57
(br s, 3H), 1.48 (br s, 3H). 13C NMR (CDCl3) δ: 147.7,
145.8, 145.5, 136.0, 135.8, 126.8, 121.3, 110.9, 109.1,
108.3, 100.9, 80.8, 35.6, 30.1, 18.9, 11.6. Anal. calcd. for
C16H20O3: C 73.52, H 7.74; found: C 73.59, H 7.81.
1
2857. H NMR (CDCl3) δ: 7.20 (t, J = 8.0 Hz, 1H), 6.80 (d,
J = 8.0 Hz, 1H), 6.76–6.73 (m, 2H), 5.57 (tdq, J = 7.1, 1.2,
1.2 Hz, 1H), 5.53 (q, J = 6.8 Hz, 1H), 4.40 (s, 1H), 3.81 (s,
3H), 2.68 (t, J = 7.6 Hz, 2H), 2.38 (dt, J = 7.6, 7.6 Hz, 2H),
2.04–1.97 (m, 1H), 1.91–1.83 (m, 1H), 1.65 (d, J = 6.8 Hz,
3H), 1.57 (br s, 1H), 1.46 (s, 3H), 0.92 (t, J = 7.6 Hz, 3H).
13C NMR (CDCl3) δ: 159.8, 144.0, 142.0, 136.4, 129.5,
125.8, 121.1, 120.3, 114.5, 111.2, 80.6, 55.4, 36.0, 29.8,
20.5, 13.7, 13.1, 12.4.
(E)-7-(3,4-Methylenedioxyphenyl)-2,4-dimethyl-1,4-hepta-
dien-3-one (11e): colorless oil. Rf 0.38 (EtOAc/Hex, 1:4). IR
1
(thin film, cm–1): 2922, 2863, 1652. H NMR (CDCl3) δ:
6.73 (d, J = 7.8 Hz, 1H), 6.67 (d, J = 1.7 Hz, 1H), 6.62 (dd,
J = 7.8, 1.7 Hz, 1H), 6.37 (tq, J = 7.2, 1.3 Hz, 1H), 5.93 (s,
2H), 5.55 (dq, J = 1.5, 1.5 Hz, 1H), 5.34 (br s, 1H), 2.69 (t,
J = 7.5 Hz, 2H), 2.51 (dt, J = 7.5, 7.5 Hz, 2H), 1.93 (br s,
3H), 1.79 (br s, 3H). 13C NMR (CDCl3) δ: 200.8, 147.9,
146.1, 144.0, 143.0, 136.6, 135.2, 123.0, 121.3, 108.9,
108.4, 101.1, 34.7, 31.1, 19.4, 12.5.
Dienol 12c was oxidized with barium manganate per the
procedure described for 11a to give (E,E′)-8-(3-
methoxyphenyl)-3-ethyl-5-methyl-2,5-octadien-4-one (11c)
as a pale yellow oil. Rf 0.69 (EtOAc/Hex, 1:1). IR (thin
1
film, cm–1): 2962, 2931, 2836, 1634. H NMR (CDCl3) δ:
7.22 (t, J = 7.8 Hz, 1H), 6.79–6.73 (m, 3H), 6.12 (tq, J =
7.2, 1.5 Hz, 1H), 6.00 (q, J = 7.0 Hz, 1H), 3.80 (s, 3H), 2.74
(t, J = 7.6 Hz, 2H), 2.53 (dt, J = 7.6, 7.6 Hz, 2H), 2.34 (q,
J = 7.6 Hz, 2H), 1.79 (br s, 3H), 1.76 (d, J = 7.0 Hz, 3H),
0.93 (t, J = 7.6 Hz, 3H). 13C NMR (CDCl3) δ: 201.5, 159.9,
143.4, 143.1, 140.8, 137.6, 135.8, 129.6, 121.0, 114.6,
111.4, 55.4, 35.1, 30.4, 20.2, 14.1, 13.2, 13.1.
(E,E′)-8-(3,4-Methylenedioxyphenyl)-3-ethyl-5-methyl-2,5-
octadien-4-one (11f)
The general procedures described for 11c were followed
using 9c in place of 9b.
(E,E′)-8-(3,4-Methylenedioxyphenyl)-3-ethyl-5-methyl-
2,5-octadien-4-ol (12f): pale yellow oil. Rf 0.25 (EtOAc/Hex,
1
1:4). IR (thin film, cm–1): 3438 (br), 2962, 2927, 2872. H
(E)-1-Cyclohexenyl-5-(3-methoxyphenyl)-2-methyl-2-
penten-1-one (11d)
The general procedures described for 11c were followed
using cyclohexanone trisyl hydrazone in place of 3-
pentanone trisyl hydrazone.
NMR (CDCl3) δ: 6.72 (d, J = 7.9 Hz, 1H), 6.68 (d, J =
1.7 Hz, 1H), 6.63 (dd, J = 7.9, 1.7 Hz, 1H), 5.91 (s, 2H),
5.58–5.48 (m, 2H), 4.39 (br s, 1H), 2.61 (t, J = 7.6 Hz, 2H),
2.33 (dt, J = 7.6, 7.6 Hz, 2H), 2.06 (dq, J = 13.6, 7.4 Hz,
1H), 1.87 (dq, J = 13.0, 7.4 Hz, 1H), 1.65 (d, J = 6.7 Hz,
3H), 1.59 (br s, 1H), 1.45 (br s, 3H), 0.91 (t, J = 7.6 Hz,
3H). 13C NMR (CDCl3) δ: 147.7, 145.7, 141.9, 136.4, 136.2,
125.6, 121.3, 120.3, 109.1, 108.3, 100.9, 80.6, 35.7, 30.2,
20.6, 13.7, 13.2, 12.5.
(E)-1-Cyclohexenyl-5-(3-methoxyphenyl)-2-methyl-2-
penten-1-ol (12d): pale yellow oil. Rf 0.26 (EtOAc/Hex,
1
1:4). IR (thin film, cm–1): 3418 (br), 2924, 2855, 2835. H
NMR (CDCl3) δ: 7.19 (t, J = 7.6 Hz, 1H), 6.79 (d, J =
7.6 Hz, 1H), 6.76–6.72 (m, 2H), 5.73 (dddd, J = 3.4, 3.4,
1.8, 1.8 Hz, 1H), 5.51 (tqd, J = 7.1, 1.2, 1.2 Hz, 1H), 4.30
(s, 1H), 3.80 (s, 3H), 2.67 (t, J = 7.6 Hz, 2H), 2.38 (dt, J =
7.6, 7.6 Hz, 2H), 2.07–2.02 (m, 2H), 1.80–1.67 (m, 2H),
1.62–1.51 (m, 5H), 1.46 (s, 3H). 13C NMR (CDCl3) δ: 159.8,
143.9, 138.0, 136.2, 129.4, 125.7, 122.8, 121.1, 114.5, 111.2,
80.9, 55.3, 36.0, 29.7, 25.2, 24.6, 22.9, 22.8, 12.3. Anal.
calcd. for C19H26O2: C 79.68, H 9.15; found C 79.41, H 9.12.
(E)-1-Cyclohexenyl-5-(3-methoxyphenyl)-2-methyl-2-
penten-1-one (11d): pale yellow oil. Rf 0.38 (EtOAc/Hex,
(E,E′)-8-(3,4-Methylenedioxyphenyl)-3-ethyl-5-methyl-
2,5-octadien-4-one (11f): colorless oil. Rf 0.40 (EtOAc/Hex,
1
1:4). H NMR (CDCl3) δ: 6.74 (d, J = 7.8 Hz, 1H), 6.68 (d,
J = 1.5 Hz, 1H), 6.62 (dd, J = 7.8, 1.5 Hz, 1H), 6.11 (tq, J =
7.1, 1.3 Hz, 1H), 6.01 (q, J = 7.0 Hz, 1H), 5.93 (s, 2H), 2.68
(t, J = 7.4 Hz, 2H), 2.48 (dt, J = 7.4, 7.4 Hz, 2H), 2.34 (q,
J = 7.5 Hz, 2H), 1.79 (d, J = 7.0 Hz, 3H),1.78 (s, 3H), 0.94
(t, J = 7.5 Hz, 3H). 13C NMR (CDCl3) δ: 201.5, 147.8,
146.0, 143.2, 140.8, 137.6, 135.7, 135.3, 121.4, 109.0,
108.3, 101.0, 34.8, 30.9, 20.2, 14.1, 13.2, 13.1. Anal. calcd.
for C18H22O3: C 75.50, H 7.74; found: C 75.52, H 7.73.
1
1:4). IR (thin film, cm–1): 2933, 2858, 2836, 1632. H NMR
(CDCl3) δ: 7.22 (ddd, J = 7.6, 7.6, 1.0 Hz, 1H), 6.81–6.74
(m, 3H), 6.31 (ddd, J = 3.9, 2.2, 1.7 Hz, 1H), 6.12 (tq, J =
7.2, 1.5 Hz, 1H), 3.81 (s, 3H), 2.75 (t, J = 7.6 Hz, 2H), 2.54
(dt, J = 7.6, 7.6 Hz, 2H), 2.27–2.23 (m, 2H), 2.19–2.14 (m,
2H), 1.80 (d, J = 1.4 Hz, 3H), 1.69–1.57 (m, 4H). 13C NMR
(E)-1-Cyclohexenyl-5-(3,4-methylendioxyphenyl)-2-methyl-
2-penten-1-one (11g)
The general procedures described for 11d were followed
using 9c in place of 9b.
© 2004 NRC Canada