A. Zörb, R. Brückner
FULL PAPER
a slightly yellow oil. H NMR (300 MHz, CDCl3/TMS): δ = 0.90
1
= 7.5, J8,9 = 7.4 Hz, 8-H2), 1.59 (tt, J7,6 = 7.6, J7,8 = 7.5 Hz, 7-H2),
(t, J8,7 = 7.3 Hz, 8-H3), 1.32 (qt, J7,8 = 7.5, J7,6 = 7.4 Hz, 7-H2), 2.46 (mc, 2-H), 2.54 (t, J6,7 = 7.5 Hz, 6-H2), 6.04 (dd, J4,3 = 16.0,
4
1.58 (tt, J6,7 = 7.5, J6,5 = 7.4 Hz, 6-H2), 1.88 (dd, J1,2 = 6.8, J1,3 4J4,2 = 1.5 Hz, 4-H), 6.78 (dd, J3,4 = 16.0, J3,2 = 6.6 Hz, 3-H) ppm.
= 1.7 Hz, 1-H3), 2.50 (t, J5,6 = 7.5 Hz, 5-H2), 6.11 (dq, J3,2 = 15.9, 13C NMR (100.61 MHz, CDCl3): δ = 14.0 (C-9), 21.4 (2ϫ2-Me),
4J3,1 = 1.6 Hz, 3-H), 6.83 (dq, J2,3 = 15.7, J2,1 = 6.8 Hz, 2-H) ppm.
22.5 (C-8), 26.5 (C-2), 31.2 (C-7), 40.0 (C-6), 127.6 (C-4), 153.3 (C-
13C NMR (100.61 MHz, CDCl3): δ = 13.9 (C-8), 18.3 (C-1), 22.5 3), 201.4 (C=O) ppm. IR (film): ν = 2960, 2935, 2875, 1695, 1675,
˜
(C-7), 26.5 (C-6), 39.9 (C-5), 132.1 (C-2), 142.4 (C-3), 200.8
1630, 1465, 1365, 1265, 1190, 1130, 1065, 985, 915, 745, 465 cm–1.
(C=O) ppm. IR (film): ν = 3530, 3035, 2960, 2935, 2875, 1700, C10H18O (154.2): calcd. C 77.87, H 11.76; found C 77.58, H 11.65.
˜
1675, 1635, 1445, 1410, 1375, 1325, 1285, 1260, 1190, 1140, 1115,
1060, 970, 935, 735, 630, 530 cm–1. C8H14O (126.2): calcd. C 76.14,
H 11.18; found C 75.9, H 11.09.
(E)-2-Methyldec-5-en-4-one (1g): This compound (5.8 g, 69%) was
prepared from 3-methylbutanoyl chloride (4.26 mL, 6.03 g,
50.0 mmol) and pentanal (15.5 mL, 21.5 g, 250 mmol, 5 equiv.) as
described for 1d. Flash chromatography (5ϫ20 cm, 50 mL, cyclo-
hexane/EtOAc 9:1) provided the title compound (fractions 4–12,
5.8 g, 69%) as a slightly yellow oil. 1H NMR (300 MHz, CDCl3/
TMS): δ = 0.88 (t, J10,9 = 7.6 Hz, 10-H3), superimposed by 0.89 (d,
J2-Me,2 = 6.8 Hz, 2ϫ2-CH3), 1.25–1.46 (m, 8-H2, 9-H2), 2.05–2.21
(m, 2-H, 7-H2), 2.36 (d, J3,2 = 7.0 Hz, 3-H2), 6.05 (dt, J5,6 = 15.7,
4J5,7 = 1.4 Hz, 5-H), 6.77 (dt, J6,5 = 15.8, J6,7 = 6.9 Hz, 6-H) ppm.
13C NMR (100.61 MHz, CDCl3): δ = 13.8 (C-10), 22.3 (2ϫ2-Me),
22.7 (C-9), 25.2 (C-2), 30.3 (C-8), 32.2 (C-7), 49.1 (C-3), 130.8 (C-
(E)-Undec-6-en-5-one (1d): MePPh3+Br– (35.7 g, 100 mmol,
2.0 equiv.) was suspended in THF (150 mL) at 0 °C. nBuLi (42 mL,
2.5 , 105 mmol, 2.1 equiv.) was added over 15 min. After 30 min
a solution of pentanoyl chloride (4.25 mL, 6.02 g, 50.0 mmol) in
THF (40 mL) was added and the mixture was allowed to warm to
room temp. After 3 h the reaction mixture was poured into H2O
(500 mL), extracted with Et2O (5ϫ80 mL), and dried with MgSO4.
After evaporation of the solvent, CH2Cl2 (80 mL) and pentanal
(15.5 mL, 21.5 g, 250 mmol, 5 equiv.) were added. After 3 d the sol-
vent was removed under reduced pressure. Flash chromatography
(5ϫ20 cm, 50 mL, cyclohexane/EtOAc 9:1) provided the title com-
pound (fractions 3–10, 5.63 g, 67%) as a slightly yellow oil. 1H
NMR (300 MHz, CDCl3/TMS): δ = 0.91 (t, J1,2 = 7.3 Hz, 1-H3),
coincident with 0.91 (t, J11,10 = 7.3 Hz, 11-H3), 1.21–1.64 (m, 2-H2,
5), 147.4 (C-6), 200.6 (C=O) ppm. IR (film): ν = 2960, 2930, 2870,
˜
2360, 1695, 1675, 1630, 1505, 1465, 1405, 1365, 1335, 1295, 1250,
1200, 1170, 1150, 1105, 1060, 1020, 980, 915, 745, 670 cm–1.
C11H20O (168.3): calcd. C 78.51, H 11.98; found C 78.17, H 11.95.
4
3-H2, 9-H2, 10-H2), 2.21 (tdd, J8,9 = 7.2, J8,7 = 6.9, J8,6 = 0.7 Hz,
(E)-2,8-Dimethyl-non-5-en-4-one (1h): This compound (5.1 g, 61%)
was prepared from 3-methylbutanoyl chloride (4.26 mL, 6.03 g,
50.0 mmol) and 3-methylbutanal (26.8 mL, 21.5 g, 250 mmol,
5 equiv.) as described for 1d. Flash chromatography (5ϫ20 cm,
50 mL, cyclohexane/EtOAc 9:1) provided the title compound (frac-
tions 4–12, 5.1 g, 61%) as a slightly yellow oil. 1H NMR (300 MHz,
CDCl3/TMS): δ = 0.85 (d, J8-Me,8 = 6.9 Hz, 2ϫ8-CH3), superim-
4
8-H2), 2.52 (t, J4,3 = 7.5 Hz, 4-H2), 6.09 (dt, J6,7 = 15.8, J6,8
=
1.5 Hz, 6-H), 6.82 (dt, J7,6 = 15.8, J7,8 = 6.9 Hz, 7-H) ppm. 13C
NMR (100.61 MHz, CDCl3): δ = 13.90 (C-1), 13.97 (C-11), 22.3
(C-2), 22.5 (C-10), 26.6 (C-3), 30.3 (C-9), 32.2 (C-8), 39.9 (C-4),
130.42 (C-6), 147.3 (C-7), 201.1 (C=O) ppm. IR (film): ν = 3740,
˜
2960, 2930, 2870, 2360, 2340, 1700, 1675, 1630, 1510, 1465, 1460,
1410, 1380, 1185, 1145, 1100, 1060, 1020, 980, 915, 745 cm–1.
C11H20O (168.3): calcd. C 78.51, H 11.98; found C 78.83, H 12.07.
posed by 0.86 (d, J2-Me,2 = 6.6 Hz, 2ϫ2-CH3), 1.69 (qqt., J2,1
=
6.7, J2,2-Me = 6.7, J2,3 = 6.7 Hz, 2-H), 1.99–2.14 (m, 7-H2, 8-H),
4
2.32 (d, J3,2 = 6.9 Hz, 3-H2), 6.00 (dt, J5,6 = 15.8, J5,7 = 1.4 Hz,
(E)-9-Methyldec-6-en-5-one (1e): This compound (5.2 g, 62%) was
prepared from pentanoyl chloride (4.25 mL, 6.02 g, 50.0 mmol) and
3-methylbutanal (26.8 mL, 21.5 g, 250 mmol, 5 equiv.) as described
for 1d. Flash chromatography (5ϫ20 cm, 50 mL, cyclohexane/
EtOAc 9:1) provided the title compound (fractions 4–7, 5.2 g, 62%)
as a slightly yellow oil. 1H NMR (300 MHz, CDCl3/TMS): δ =
5-H), 6.71 (dt, J6,5 = 15.3, J6,7 = 7.7 Hz, 6-H) ppm. 13C NMR
(100.61 MHz, CDCl3): δ = 22.5 (2ϫ2-Me), 22.8 (2ϫ8-Me), 25.3
(C-2), 27.0 (C-8), 41.8 (C-7), 49.2 (C-3), 131.9 (C-5), 146.2 (C-6),
200.6 (C=O) ppm. IR (film): ν = 2960, 2930, 2870, 2365, 1695,
˜
1670, 1630, 1465, 1385, 1365, 1300, 1195, 1170, 1015, 980 cm–1.
C11H20O (168.3): calcd. C 78.51, H 11.98; found C 78.22, H 12.15.
0.91 (t, J1,2 = 7.3 Hz, 1-H3), superimposed by 0.92 (d, J9-Me,9
=
6.7 Hz, 2ϫ9-CH3), 1.33 (qt, J2,1 = 7.5, J2,3 = 7.4 Hz, 2-H2), 1.59
(tt, J3,4 = 7.5, J3,2 = 7.4 Hz, 3-H2), 1.76 (qqt, J9,9-Me = J9,10 = 6.8,
(3S,4R)-3,4-Dihydroxypentan-2-one
(2a):
(E)-Pent-3-en-2-one
(0.84 g, 10 mmol) was added at 0 °C to a stirred mixture of K2O-
sO2(OH)4 (36.8 mg, 1 mol-%), (DHQD)2PHAL (390 mg, 5 mol-%),
K2CO3 (4.15 g, 30.0 mmol, 3.0 equiv.), and K3Fe(CN)6 (9.88 g,
30.0 mmol, 3.0 equiv.) in tBuOH (50 mL)/H2O (50 mL). After 3 d,
satd. aq. Na2SO3 (50 mL) was added. After extraction with EtOAc
(4ϫ30 mL), drying over MgSO4, and evaporation of the solvent
the crude title compound was obtained. Flash chromatography
(2ϫ20 cm, 10 mL, cyclohexane/EtOAc 1:1) provided the title com-
pound (fractions 18–25, 606 mg, 5.13 mmol, 51%) as a colorless
oil. [α]2D0 = +44.0 (c = 1.0, CHCl3); the ee was 92% according to
chiral GC (CP-Chirasil-Dex CB, 25 mϫ0.25 mm, Cat. No.
CP 7502, 80 °C, 10 min, then 1 °Cmin–1 Ǟ170 °C, 60 kPa H2) with
4
J9,8 = 6.7 Hz, 9-H), 2.09 (ddd, J8,7 = 7.1, J8,9 = 7.1, J8,6 = 0.7 Hz,
4
8-H2), 2.52 (t, J4,3 = 7.4 Hz, 4-H2), 6.07 (dt, J6,7 = 15.8, J6,8
=
1.4 Hz, 6-H) 6.79 (dt, J7,6 = 15.7, J7,8 = 7.4 Hz, 7-H) ppm. 13C
NMR (100.61 MHz, CDCl3): δ = 14.0 (C-1), 22.46 (2ϫ9-Me*),
22.52 (C-2*), 26.6 (C-3), 28.0 (C-9), 40.0 (C-4), 41.8 (C-8), 131.5
(C-6), 146.1 (C-7), 201.0 (C=O) ppm (* assignment interchange-
able). IR (film): ν = 3385, 3180, 2960, 2935, 2870, 2730, 2360, 1975,
˜
1695, 1675, 1630, 1560, 1465, 1440, 1410, 1385, 1370, 1350, 1320,
1310, 1260, 1190, 1165, 1145, 1095, 1070, 1025, 980, 930, 890, 855,
725, 695, 630, 545 cm–1. C11H20O (168.3): calcd. C 78.51, H 11.98;
found C 78.20, H 12.01.
(E)-2-Methylnon-3-en-5-one (1f): This compound (6.3 g, 81%) was
prepared from pentanoyl chloride (4.26 mL, 6.03 g, 50.0 mmol) and
isobutyraldehyde (22.8 mL, 18.0 g, 250 mmol, 5 equiv.) as de-
scribed for 1d. Flash chromatography (4ϫ20 cm, 50 mL, cyclohex-
ane/EtOAc 10:1) provided the title compound (fractions 5–16,
6.3 g, 81%) as a slightly yellow oil. 1H NMR (400 MHz, CDCl3/
the bis(trimethylsilyl ether) of the title compound; tret(3S,4R) =
9.71 min, tret(3R,4S) = 10.66 min. 1H NMR (300 MHz, CDCl3/
TMS): δ = 1.35 (d, J5,4 = 6.4 Hz, 5-H3), 1.86 (d, J4-OH,4 = 9.6 Hz,
4-OH), 2.28 (s, 1-H3), 3.68 (d, J3-OH,3 = 4.2 Hz, 3-OH), 4.00 (dd,
J3,3-OH = 4.1, J3,4 = 2.0 Hz, 3-H), 4.21 (mc, 4-H) ppm. 13C NMR
(100.61 MHz, CDCl3): δ = 20.4 (C-5), 25.5 (C-1), 68.1 (C-4), 80.5
TMS): δ = 0.92 (t, J9,8 = 7.3 Hz, 9-H3), 1.07 (d, J2-Me,2 = 6.8 Hz, (C-3), 208.0 (C=O) ppm. IR (film): ν = 3405, 2980, 2930, 1715,
˜
2-CH3), coincident with 1.07 (d, J1,2 = 6.8 Hz, 1-H3), 1.34 (tq, J8,7
1360, 1245, 1140, 1080, 1010, 915, 745, 665 cm–1.
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Eur. J. Org. Chem. 2010, 4785–4801