with Et2O (3 × 20 mL). The combined organic layers were washed
with a 1 : 1 sat. aq. NaHCO3–brine mixture (1 × 30 mL), dried
(MgSO4), filtered and concentrated in vacuo. The residue was
purified by flash chromatography on silica gel (gradient: 2–4%
Et2O in hexanes) to give 94 (146 mg, 92%) as a colourless oil. 1H-
NMR, 13C-NMR and HSQC analysis revealed the product to be
a 1.4 : 1 mixture of anomers at the C-15 position. Rf = 0.17 (25 :
microwave reactor tube (9.0× 1.5 cm) equipped with a stirrer bar at
room temperature. The solution was purged with ethylene (from a
balloon) for 5 min, then sealed and microwaved (2 × 20 min, 100 W
microwave power, 55 ◦C maximum temperature). After cooling to
room temperature, the reactor tube was opened, another portion
of catalyst 88 (3.8 mg, 4.5 lmol) was added, the mixture was purged
with ethylene for 5 min, then the tube was sealed and microwaved
again (1 × 50 min, 100 W microwave power, 55 ◦C maximum
temperature). After cooling to room temperature, the reactor
tube was opened and the mixture concentrated. The residue was
purified by flash chromatography on silica gel (gradient: 2–2.5%
Et2O in hexanes) to give 96 (80 mg, 60%) as a colourless oil. 1H-
NMR, 13C-NMR and HSQC analysis revealed the product to be
a 1.4 : 1 mixture of anomers at the C-15 position. Rf = 0.41 (23 :
2 hexanes–Et2O); [a]2D5 −10.5◦ (c 1.22 in CH2Cl2); mmax/cm−1 (film)
2956, 2860, 1732, 1615, 1514, 1471, 1250, 1123, 837; dH (600 MHz,
C6D6, 343 K) 7.30 [4 H, d, J 8.4 Hz, ArH (anomers a and b)], 6.84
[4 H, d, J 8.4 H, ArH (a and b)], 6.36 [2 H, dd, J 17.7, 11.2 Hz,
5-H (a and b)], 5.94 [1 H, ddd, J 17.3, 10.5 and 6.9 Hz, 4-H (a)],
5.90 [1 H, ddd, J 17.2, 10.3 and 6.7 Hz, 4-H (b)], 5.55 [2 H, d, J
1 hexanes–Et2O); [a]25 −1.9◦ (c 0.48 in CH2Cl2); mmax/cm−1 (film)
D
2953, 2856, 2280, 1731, 1614, 1472, 1463, 1251, 1095, 837, 776; dH
(600 MHz, C6D6, 343 K) 7.26 [4 H, d, J 8.6 Hz, ArH (anomers a
and b)], 6.80 [4 H, d, J 8.6 Hz, ArH (a and b)], 5.92 [1 H, ddd, J
17.2, 10.4 and 6.8 Hz, 4-H (a)], 5.88 [1 H, ddd, J 17.2, 10.4 and
6.8 Hz, 4-H (b)], 5.38 [2 H, d, J 9.1 Hz, 11-H (a and b)], 5.22
=
=
[1 H, d, J 17.2 Hz, 4 CH2 (a)], 5.19 [1 H, d, J 17.2 Hz, 4 CH2
=
(b)], 5.03–5.08 [3 H, m, 4 CH2 (a) and 25-H (a and b)], 5.01 [1 H,
=
d, J 10.4 Hz, 4 CH2 (b)], 4.74–4.77 [2 H, m, 7-H (a and b)], 4.57
[2 H, d, J 11.2 Hz, OCH2Ar (a and b)], 4.49 [2 H, d, J 11.2 Hz,
OCH2Ar (a and b)], 4.46 [1 H, t, J 6.8 Hz, 3-H (a)], 4.42 [1 H, t, J
6.8 Hz, 3-H (b)], 4.35 [2 H, d, J 8.7 Hz, 14-H (a and b)], 3.97–4.02
[2 H, m, 19-H (a and b)], 3.86–3.89 [5 H, m, 16-H (a and b), 21-H (a
and b) and 24-H (b)], 3.83–3.85 [1 H, m, 24-H (a)], 3.72–3.75 [2 H,
m, 9-H (a and b)], 3.39 [6 H, s, ArOCH3 (a and b)], 3.32 [3 H,
s, OCH3 (a)], 3.31 [3 H, s, OCH3 (b)], 2.83–2.87 [2 H, m, 10-H (a
and b)], 2.72 [2 H, d, J 13.9 Hz, 13-H (a and b)], 2.57 [2 H, qd,
J 7.0, 6.8 Hz, 2-H (a and b)], 2.38–2.42 [2 H, m, 13-H (a and b)],
2.12–2.17 [6 H, m, 5-H (a and b), 8-H (a and b) and 17-H (a and
b)], 1.98–2.05 [4 H, m, 8-H (a and b) and 20-H (a and b)], 1.75
[6 H, s, 12-CH3 (a and b)], 1.70 [10 H, m, 17-H (a and b), 18-H
(a and b), 20-H (a and b), 23-H (a and b) and 26-H (a and b)],
1.50–1.69 [8 H, m, 22-H (a and b), 22-H (a and b), 23-H (a and b)
and 26-H (a and b)], 1.30–1.49 [10 H, m, 18-H (a and b), 27-H (a
and b), 27-H (a and b), 28-H (a and b) and 28-H (a and b)], 1.29
[3 H, d, J 7.0 Hz, 2-CH3 (a)], 1.28 [3 H, d, J 7.0 Hz, 2-CH3 (b)],
1.17 [6 H, d, J 6.8 Hz, 10-CH3 (a and b)], 1.03 [18 H, s, SiC(CH3)3
and SiC(CH3)3], 1.01 [18 H, s, SiC(CH3)3 and SiC(CH3)3], 1.01
[9 H, s, SiC(CH3)3], 1.00 [18 H, s, SiC(CH3)3 and SiC(CH3)3], 0.98
[9 H, s, SiC(CH3)3], 0.97 [18 H, s, SiC(CH3)3 and SiC(CH3)3], 0.96
[9 H, s, SiC(CH3)3], 0.96 [9 H, s, SiC(CH3)3], 0.90 [3 H, t, J 7.1 Hz,
28-CH3 (b)], 0.88 [3 H, t, J 7.0 Hz, 28-CH3 (a)], 0.28 (6 H, s, SiCH3
and SiCH3), 0.25 (6 H, s, SiCH3 and SiCH3), 0.23 (3 H, s, SiCH3),
0.21 (3 H, s, SiCH3), 0.19 (6 H, s, SiCH3 and SiCH3), 0.18 (3 H, s,
SiCH3), 0.18 (6 H, s, SiCH3 and SiCH3), 0.17 (3 H, s, SiCH3), 0.16
(3 H, s, SiCH3), 0.15 (3 H, s, SiCH3), 0.14 (12 H, s, SiCH3, SiCH3,
SiCH3 and SiCH3), 0.11 (3 H, s, SiCH3), 0.10 (9 H, s, SiCH3,
SiCH3 and SiCH3), 0.08 (3 H, s, SiCH3), 0.06 (3 H, s, SiCH3); dC
(150 MHz, C6D6, 343 K) 173.6, 173.5, 159.8, 140.4, 140.2, 134.1,
134.1, 131.9, 129.9, 129.8, 129.4, 129.3, 115.7, 114.2, 100.4, 86.2,
80.1, 76.7, 76.0, 75.8, 75.7, 73.4, 73.0, 72.9, 72.3, 71.9, 69.8, 69.4,
68.9, 68.9, 67.9, 61.9, 61.8, 54.9, 47.6, 44.5, 44.2, 43.3, 41.2, 36.0,
34.5, 34.5, 31.8, 30.6, 28.7, 28.6, 28.4, 27.9, 27.7, 26.7, 26.6, 26.4,
26.2, 26.1, 26.1, 25.4, 24.1, 23.1, 22.8, 19.1, 18.5, 18.4, 18.4, 18.3,
16.5, 16.1, 14.1, 14.0, 13.5, 13.2, −2.5, −3.5, −3.6, −3.7, −3.9,
−4.0, −4.1, −4.2, −4.3, −4.5, −4.6; HRMS (ES+) m/z calc. for
C78H150O12Si6Na ([MNa]+): 1469.9635, found 1469.9624.
=
17.7 Hz, 5 CH2 (a and b)], 5.45 [2 H, d, J 9.1 Hz, 11-H (a and
=
b)], 5.23 [1 H, d, J 17.3 Hz, 4 CH2 (a)], 5.20 [1 H, d, J 17.2 Hz,
=
=
=
4 CH2 (b)], 5.02–5.11 [10 H, m, 4 CH2 (a and b), 5 CH2 (a
=
=
and b), 6 CH2 (a and b), 6 CH2 (a and b) and 25-H (a and b)],
4.61–4.65 [2 H, m, 7-H (a and b)], 4.55 [2 H, d, J 11.3 Hz, OCH2Ar
(a and b)], 4.42 [4 H, m, 3-H (a and b) and OCH2Ar (a and b)],
4.35 [2 H, d, J 8.7 Hz, 14-H (a and b)], 3.98–4.02 [2 H, m, 19-H
(a and b)], 3.88–3.93 [5 H, m, 16-H (a and b), 21-H (a and b) and
24-H (b)], 3.86–3.88 [1 H, m, 24-H (a)], 3.50–3.53 [2 H, m, 9-H (a
and b)], 3.40 [6 H, s, ArOCH3 (a and b)], 3.33 [3 H, s, OCH3 (a)],
3.32 [3 H, s, OCH3 (b)], 2.89–2.94 [2 H, m, 10-H (a and b)], 2.71
[2 H, d, J 14.0 Hz, 13-H (a and b)], 2.58–2.63 [2 H, m, 2-H (a and
b)], 2.43–2.47 [2 H, m, 13-H (a and b)], 1.99–2.19 [9 H, m, 8-H (a
and b), 8-H (a and b), 17-H (a), 20-H (a and b) and 26-H (a and
b)], 1.79 [6 H, s, 12-CH3 (a and b)], 1.74–1.90 [9 H, m, 17-H (b),
18-H (a and b), 20-H (a and b), 22-H (a and b), 26-H (a and b)],
1.49–1.69 [8 H, m, 17-H (a and b), 22-H (a and b), 23-H (a and b)
and 23-H (a and b)], 1.31–1.48 [10 H, m, 18-H (a and b), 27-H (a
and b), 27-H (a and b), 28-H (a and b) and 28-H (a and b)], 1.31
[3 H, d, J 6.8 Hz, 2-CH3 (b)], 1.30 [3 H, d, J 6.9 Hz, 2-CH3 (a)],
1.23 [6 H, d, J 6.9 Hz, 10-CH3 (a and b)], 1.06 [18 H, s, SiC(CH3)3
and SiC(CH3)3], 1.03 [18 H, s, SiC(CH3)3 and SiC(CH3)3], 1.03 [9
H, s, SiC(CH3)3], 1.02 [18 H, s, SiC(CH3)3 and SiC(CH3)3], 1.00
[18 H, s, SiC(CH3)3 and SiC(CH3)3], 0.99 [9 H, s, SiC(CH3)3], 0.98
[9 H, s, SiC(CH3)3], 0.97 [9 H, s, SiC(CH3)3], 0.92 [3 H, t, J 7.2 Hz,
28-CH3 (b)], 0.90 [3 H, t, J 6.9 Hz, 28-CH3 (a)], 0.31 (6 H, s,
SiCH3 and SiCH3), 0.28 (6 H, s, SiCH3 and SiCH3), 0.25 (3 H, s,
SiCH3), 0.23 (3 H, s, SiCH3), 0.21 (6 H, s, SiCH3 and SiCH3),
0.20 (3 H, s, SiCH3), 0.19 (3 H, s, SiCH3), 0.18 (3 H, s, SiCH3),
0.17 (3 H, s, SiCH3), 0.16 (3 H, s, SiCH3), 0.16 (6 H, s, SiCH3
and SiCH3), 0.14 (6 H, s, SiCH3 and SiCH3), 0.13 (3 H, s, SiCH3),
0.12 (3 H, s, SiCH3), 0.11 (6 H, s, SiCH3 and SiCH3), 0.10 (3 H, s,
SiCH3), 0.09 (3 H, s, SiCH3), 0.08 (3 H, s, SiCH3); dC (150 MHz,
C6D6, 343 K) 173.7, 173.6, 159.8, 150.1, 140.4, 140.2, 136.0, 133.7,
132.2, 130.3, 129.2, 129.0, 115.7, 115.1, 114.2, 114.0, 100.4, 80.0,
76.7, 76.1, 75.9, 75.7, 73.4, 73.0, 71.8, 71.3, 69.9, 69.5, 69.0, 69.0,
67.9, 54.9, 47.7, 44.4, 43.2, 39.8, 35.5, 34.6, 34.5, 31.8, 30.5, 30.1,
28.7, 28.7, 28.4, 27.9, 27.8, 26.7, 26.5, 26.2, 26.1, 25.4, 23.1, 22.9,
19.1, 18.6, 18.4, 18.3, 16.4, 16.2, 14.1, 14.0, 13.5, 13.3, −2.5, −3.5,
Diene 96
Alkyne 94 (130 mg, 90 lmol) and Grubbs second-generation
catalyst 88 (3.8 mg, 4.5 lmol) were dissolved in CH2Cl2 (7 mL) in a
2148 | Org. Biomol. Chem., 2006, 4, 2119–2157
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The Royal Society of Chemistry 2006
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