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L. C. Bouchez et al. / Tetrahedron 61 (2005) 11473–11487
1
1J(C,H)Z139 Hz, C(2)), 25.8 (q, J(C,H)Z142 Hz, t-Bu),
C(4)), 56.7 (t, 1J(C,H)Z132 Hz, C(10)), 49.1 (d, 1J(C,H)Z
1
1
1
23.2 (q, J(C,H)Z130 Hz, Me-C(20)), 18.2 (q, J(C,H)Z
140 Hz, C(20)), 29.3 (q, J(C,H)Z133 Hz, C(1)), 23.4 (q,
129 Hz, Me-C(4)), 15.4 (q, 1J(C,H)Z128 Hz, Me-C(6)),
1J(C,H)Z133 Hz, Me-C(5)), 23.2 (q, 1J(C,H)Z136 Hz,
C(8)), 14.9 (q, 1J(C,H)Z132 Hz, Me-C(3)), 10.7 (q,
1
15.0 (s, Cquat-tBu), 13.8 (q, J(C,H)Z132 Hz, Me-C(2)),
K4.7 (q, 1J(C,H)Z126 Hz, MeSi–C(3)), K5.3 (q,
1J(C,H)Z129 Hz, C(30)), 9.8 (q, J(C,H)Z130 Hz, C(30)).
1
1J(C,H)Z129 Hz,
MeSi–C(3)).
CI-MS
(NH3):
MALDI-HRMS: calcd for C14H26O4SCKC: 329.1189 and
C14H26O4SCNaC: 313.1449, found: 313.2285. Anal. Calcd
for C14H26O4S (290.16): C, 57.90; H, 9.02. Found: C, 57.86;
H, 9.02.
C28H46SSiO7, m/z 555 (25, [MC1]C), 108 (100). Anal.
Calcd for C28H46O7SSi (554.27): C, 60.62; H, 8.36. Found:
C, 60.80; H, 8.49.
4.3. General procedure for the preparation of oxo-(E)-b,
g-unsaturated sulfones (20,21) using enoxysilanes
4.3.2. 9:1 Mixture of (G)-(2RS,3RS,4E,6RS)-3-{[(tert-
butyl)dimethylsilyl]oxy}-6-[(2-methylprop-2-enyl) sul-
fonyl]-2,4-dimethyl-1-(2,4,6-trimethoxyphenyl)hept-4-
en-1-one ((G)-20b) and (G)-(2RS,3RS,4E,6SR)-3-{[(tert-
butyl)dimethylsilyl]oxy}-6-[(2-methylprop-2-enyl) sul-
fonyl]-2,4-dimethyl-1-(2,4,6-trimethoxyphenyl)hept-4-
en-1-one ((G)-21b). This preparation followed the above
general procedure and used 16c49 (1.7 g, 5.8 mmol,
1.7 equiv), (E,E)-2-methyl-1-[(tert-butyl)dimethylsilyl]-
oxy-penta-1,3-diene 17d33b,51 (580 mg, 3.41 mmol,
1 equiv) and 3-bromo-2-methylpropene (1.15 g, 0.86 mL,
8.52 mmol, 2.5 equiv) in CH2Cl2 (5 mL). This provided a
mixture of alcohols that was treated with 2,6-lutidine
(1.82 g, 1.97 mL, 17.05 mmol, 5 equiv) and by TBSOTf
(2.7 g, 2.35 mL, 10.23 mmol, 3 equiv) at K78 8C (1.49 g,
3.41 mmol, 1 equiv) in anhyd CH2Cl2 (10 mL). for 1 h. The
mixture was then treated with 2 M aq soln of NaOH (2 mL)
and extracted with CH2Cl2 (40 mL, three times). The
combined organic extracts were washed with 1 M HCl
(20 mL) and with brine (40 mL, twice), dried (Na2SO4) and
the solvent was eliminated under reduced pressure. The
residue contained a,b-syn and a,b-anti diastereoisomers
(G)-20c and (G)-21c with the ratio 9:1. FC (light
petroleum ether/EtOAc 4:2, RfZ0.30) gave 1.14 g (60%)
of a 9:1 mixture of (G)-20c and (G)-21c, yellow oil. UV
(CH3CN): lmaxZ209 nm (3Z7924). IR (film): n 2987,
1694, 1606, 1456, 1421, 1305, 1265, 1155, 1130, 900,
740 cmK1. 1H NMR (400 MHz, CDCl3) of (G)-20c: d 6.09
Same procedure for the preparation of 18, 19, but using
0.5 equiv of Tf2NH introduced to the SO2CCH2Cl2
solution as a 0.5 M solution in anhyd CH2Cl2.
4.3.1. 1:1 Mixture of (G)-(3RS,4RS,5E,7RS)-4-hydroxy-
7-(2-methyl-propyl-1-sulfonyl)-3,5-dimethyloct-5-en-2-
one and ((G)-20a) (G)-(3RS,4SR,5E,7SR)-4-hydroxy-7-
(2-methyl-propyl-1-sulfonyl)-3,5-dimethyloct-5-en-2-
one ((G)-21a). This preparation applies the above
procedure using a 1:1 mixture of (E) and (Z)- 2-triethyl-
silyloxybut-2-ene (7.92 g, 43 mmol, 2 equiv), (E,E)-2-
methyl-1-trimethylsilyloxypenta-1,3-diene (4 g, 21.25
mmol, 1 equiv) and 1-iodo-2-methylpropane (4.84 g,
26.3 mmol, 5 equiv) in CH3CN (15 mL) DMF (55 mL).
FC (light petroleum ether/EtOAc 7:3, RfZ0.31) gave 6.7 g
(82%), colorless oil. UV (CH3CN): lZ219 nm (3Z5800).
IR (film, cmK1): n 3470, 2970, 2930, 2855, 1710, 1650,
1460, 1340, 1285, 1195, 1135, 1040, 740. 1H NMR
(400 MHz, CDCl3, 283 K) of (G)-20a: d 5.58 (d, 1H,
3J(H6,H7)Z10.3 Hz, H–C(6)), 4.46 (m, 2H, H–C(4)), 3.87
(dq, 1H, 3J(H7,H6)Z10.3 Hz, 3J(H7,H8)Z7.1 Hz, H–C(7)),
3
3.15 (d, 1H, J(H4,OH)Z2.6 Hz, H–OH), 2.77 (m, 3H, H–
3
3
0
0
0
0
C(1 ), H–C(3)), 2.41 (tqq, 1H, J(H2 ,H1 )Z6.4 Hz, J(H2 ,-
3
H3 a)Z6.4 Hz, J(H2 ,H3 b)Z6.4 Hz, H–C(20)), 2.26 (s, 3H,
0
0
0
3
H–C(1)), 1.87 (s, 3H, Me-C(5)), 1.50 (d, 3H, J(H8,H7)Z
7.1 Hz, H–C(8)), 1.16 (d, 3H, 3J(Me3,H3)Z6.4 Hz, Me-
(s, 2H, Har), 5.54 (d, 1H, J(H5,H6)Z10.5 Hz, H–C(5)),
3
3
0
C(3)), 1.15 (d, 3H, J(H3 ,H2 )Z6.4 Hz, H–C(3 )), 1.13 (d,
5.26 (br s, 1H, H–C(30)), 5.05 (br s, 1H, H–C(30)), 4.58 (d,
1H, 3J(H3,H2)Z6.2 Hz, H–C(3)), 3.92 (dq, 1H, 3J(H6,H5)Z
10.5 Hz, 3J(H6,H7)Z7.1 Hz, H–C(6)), 3.82 (s, 3H,
0
0
3H, J(H3 ,H2 )Z6.4 Hz, H–C(3 )). 13C NMR (100 MHz,
CDCl3, 283K) of (G)-20a: d 211.2 (s, C(2)), 142.7 (s, C(5)),
121.1 (d, 1J(C,H)Z155 Hz, C(6)), 75.2 (d, 1J(C,H)Z
3
0
0
0
2
H–OMe), 3.77 (s, 6H, H–OMe), 3.59 (d, 1H, JZ12.1 Hz,
1
2
140 Hz, C(7)), 64.1 (d, J(C,H)Z130 Hz, C(3)), 58.9 (d,
Ha–C(10)), 3.57 (d, 1H, JZ12.1 Hz, Hb–C(10)), 3.2 (qd,
1J(C,H)Z142 Hz, C(4)), 56.9 (t, J(C,H)Z136 Hz, C(10)),
1H, 3J(H2,Me2)Z7.4 Hz, 3J(H2,H3)Z6.2 Hz, H–C(2)), 1.97
(s, 3H, Me-C(4)), 1.73 (s, 3H, Me-C(20)), 1.42 (d, 3H,
3J(H7,H6)Z7.1 Hz, H–C(7)), 1.11 (d, 3H, 3J(Me2,H2)Z
7.4 Hz, Me-C(2)). 13C NMR (100.6 MHz, CDCl3) of (G)-
20c: d 209.2 (s, CO), 162.3–158.4 (s, 4C, C(ar)), 144.4 (s,
1
49.5 (d, J(C,H)Z135 Hz, C(20)), 29.4 (q, 1J(C,H)Z
1
1
129 Hz, C(1)), 23.5 (q, J(C,H)Z140 Hz, Me-C(5)), 23.3
(q, 1J(C,H)Z134 Hz, C(8)), 15.3 (q, 1J(C,H)Z131 Hz, Me-
C(3)), 14.2 (q, 1J(C,H)Z132 Hz, C(30)), 14.1 (q, 1J(C,H)Z
133 Hz, C(30)). 1H NMR (400 MHz, CDCl3, 283 K) of (G)-
21a: d 5.57 (d, 1H, 3J(H6,H7)Z10.3 Hz, H–C(6)), 4.46 (m,
2H, H–C(4)), 3.86 (dq, 1H, 3J(H7,H6)Z10.3 Hz,
3J(H7,H8)Z7.1 Hz, H–C(7)), 3.08 (d, 1H, 3J(H4,OH)Z
2.6 Hz, H–OH), 2.77 (m, 3H, H–C(10), H–C(3)), 2.41 (tqq,
1
C(20)), 133.1 (s, C(4)), 120.4 (t, J(C,H)Z149 Hz, C(30)),
1
117.9 (d, J(C,H)Z161 Hz, C(5)), 90.6 and 90.5 (d, 2C,
1J(C,H)Z161 Hz, C(ar)), 70.4 (t, 1J(C,H)Z154 Hz, C(10)),
58.1 (d, 1J(C,H)Z148 Hz, C(3)), 56.9 (d, 1J(C,H)Z133 Hz,
C(6)), 55.6 (q, 1J(C,H)Z151 Hz, C(OMe)), 51.6 (d,
3
3
3
1
1H, J(H2 ,H1 )Z6.4 Hz, J(H2 ,H3 a)Z6.4 Hz, J(H2 ,-
1J(C,H)Z146 Hz, C(2)), 25.8 (q, J(C,H)Z142 Hz, t-Bu),
0
0
0
0
0
1
1
H3 b)Z6.4 Hz, H–C(20)), 2.24 (s, 3H, H–C(1)), 1.86 (s,
23.1 (q, J(C,H)Z133 Hz, Me-C(20)), 18.3 (q, J(C,H)Z
132 Hz, Me-C(4)), 15.1 (s, Cquat-tBu)), 14.6 (q, 1J(C,H)Z
131 Hz, Me-C(6)), 12.6 (q, 1J(C,H)Z139 Hz, Me-C(2)),
K4.2 (q, 1J(C,H)Z127 Hz, Me2Si–C(3)), K5.0 (q,
1J(C,H)Z129 Hz, Me2Si–C(3)). 1H NMR (400 MHz,
CDCl3) of (G)-21c: d 6.09 (s, 2H, H–C(ar)), 5.54 (d, 1H,
3J(H5,H6)Z10.5 Hz, H–C(5)), 5.21 (br s, 1H, H–C(30)),
0
3
3H, Me-C(5)), 1.48 (d, 3H, J(H8,H7)Z7.1 Hz, H–C(8)),
3
1.16 (d, 3H, J(Me,H3)Z6.4 Hz, Me-C(3)), 1.15 (d, 3H,
3
3
0
0
0
0
0
J(H3 ,H2 )Z6.4 Hz, H–C(3 )), 1.13 (d, 3H, J(H3 ,H2 )Z
6.4 Hz, H–C(30)). 13C NMR (100 MHz, CDCl3, 283K) of
(G)-21a: d 211.1 (s, C(2)), 142.2 (s, C(5)), 119.5 (d,
1J(C,H)Z150 Hz, C(6)), 74.3 (d, J(C,H)Z148 Hz, C(7)),
1
63.9 (d, 1J(C,H)Z130 Hz, C(3)), 58.5 (d, 1J(C,H)Z141 Hz,
5.14 (br s, 1H, H–C(30)), 4.80 (d, 1H, J(H3,H2)Z7.6 Hz,
3