1-Phenylbut-3-en-1-ol (20j ؍
20k)
CH2Cl2 was added 1.1 mL of a 1 M solution of SnCl4. After
2 min, a solution of allylsilane (251 mg, 2 equiv.) in 20 mL of
CH2Cl2 was added. The reaction mixture was stirred for 30 min
and subjected to standard work-up. Flash chromatography on
silica gel (10% to 20% EA–hex) afforded 151 mg (48%) of 25 as
a colorless mixture of four isomers which could be partially
separated by HPLC: (10% EA–hex) into two cis isomers (35%,
35%) and a mixture of two trans isomers (15%, 15%). cis-25a:
Rf = 0.30 (20% EA–hex); 1H NMR (500 MHz) δ 5.88–5.78
(m, 1 H), 5.14 (m, 2 H), 4.42–4.34 (m, 1 H), 3.71–3.63 (m, 1 H),
2.364 (dd, 1 H, J = 11.7, 6.5), 2.36–2.27 (m, 1 H), 2.20–2.11
(m, 1 H, CH), 1.923 (dd, 1 H, J = 11.7, 8.5), 1.80–1.40 (m, 6 H),
1.28 (s, 3 H), 1.079 (dd, 1 H, J = 14.1, 5.2), 0.815 (dd, 1 H,
J = 14.1, 9.3), 0.046 (s, 9 H); 13C NMR δ 134.8(ϩ), 118.3(Ϫ),
85.9, 79.8(ϩ), 70.6(ϩ), 53.56(Ϫ), 42.1(Ϫ), 40.6(Ϫ), 37.2(Ϫ),
23.31(ϩ), 21.0(Ϫ), 20.8(Ϫ), Ϫ1.0(ϩ). Anal. Calcd for
C15H30O3Si: C, 62.63; H, 10.55. Found: C, 62.51; H, 10.46%.
1
Rf = 0.46 (20% EA–hex); H NMR δ 7.40–7.16 (m, 5 H), 5.80
(m, 1 H), 5.15 (m, 2 H), 4.52 (t, 1 H, J = 6.1), 2.50 (m, 2 H).
3-(Trimethylsilylmethyl)-5-tert-butyl-5-methyl-1,2-dioxaspiro-
[5.4]decane (18)
1
Rf = 0.72 (10% EA–hex); H NMR δ 4.22 (m, 1 H), 2.68 (dd,
1 H, J = 11.7, 6.9), 1.63 (dd, 1 H, J = 11.7, 8.1), 1.35 (s, 3 H),
1.08 (dd, 1 H, J = 14.1, 5.3), 0.98 (s, 9 H), 0.82 (dd, 1 H,
J = 14.1, 9.3), 0.04 (s, 9 H); 13C NMR δ 90.92, 80.58, 50.40,
36.12, 25.91, 23.06, 20.42, Ϫ0.95. Anal. Calcd for C12H26O2Si:
C, 62.56; H, 11.37. Found: C, 62.69; H, 11.41%.
cis-3-Phenyl-5-(trimethylsilylmethyl)-1,2-dioxaspiro[5.4]decane
1
Rf = 0.33 in 5% EA–hexane; H NMR (500 MHz) δ 7.45–7.25
1
cis-25b: H NMR (500 MHz) δ 5.88–5.77 (m, 1 H), 5.17–5.11
(m, 5 H), 5.29 (t, 1 H, J = 7.5), 4.49 (tt, 1 H, J = 9.3, 5.5), 3.14
(ddd, 1 H, J = 11.9, 7.9, 6.0), 2.20 (ddd, 1 H, J = 11.9, 8.5, 6.9),
1.19 (dd, 1 H, J = 14.1, 5.2), 0.90 (dd, 1 H, J = 14.1, 9.3), 0.07 (s,
9 H); 13C NMR δ 141.17, 128.62, 127.88, 126.16, 82.83, 80.11,
51.27, 20.40, Ϫ1.01. Anal. Calcd for C13H20O2Si: C, 66.05; H,
8.53. Found: C, 65.94; H, 8.41%.
(m, 2 H), 4.41–4.33 (m, 1 H), 3.71–3.64 (m, 1 H), 2.357 (dd, 1 H,
J = 11.67, 6.5), 2.34–2.27 (m, 1 H), 2.19–2.11 (m, 1 H), 1.929
(dd, 1 H, J = 11.7, 8.5), 1.75–1.35 (m, 6 H), 1.28 (s, 3 H), 1.08
(dd, 1 H, J = 13.7, 5.2), 0.814 (dd, 1 H, J = 13.7, 9.3), 0.045 (s,
9 H); 13C NMR δ 134.8(ϩ), 118.2(Ϫ), 85.9, 79.9(ϩ), 70.4(ϩ),
53.5(Ϫ), 42.0(Ϫ), 40.5(Ϫ), 37.0(Ϫ), 23.5(ϩ), 20.8(Ϫ), 20.6(Ϫ),
Ϫ1.0(ϩ). Anal Calcd for C15H30O3Si: C, 62.63; H, 10.55.
Found: C, 62.44; H, 10.32%. trans-25ab (mixture of diastereo-
trans-3-Phenyl-5-(trimethylsilylmethyl)-1,2-dioxaspiro[5.4]-
1
mers): Rf = 0.27 (20% EA–hex); H NMR (500 MHz) δ 5.87–
1
Rf = 0.33 (5% EA–hexane); H NMR (500 MHz) δ 7.45–7.28
5.77 (m, 2 H), 5.17–5.11 (m, 4 H), 4.36–4.28 (m, 2 H), 3.70–3.63
(m, 2 H), 2.51–2.45 (m, 2 H), 2.34–2.27 (m, 2 H), 2.19–2.11 (m,
2 H), 1.85–1.80 (m, 2 H), 1.66–1.40 (m, 12 H), 1.34 (s, 3 H),
1.096 (dd, 2 H, J = 14.1, 5.2), 0.840 (dd, 2 H, J = 13.7, 9.3),
0.047 (s, 18 H); 13C NMR δ 134.7 (for 2C), 118.4 (for 2C), 86.1
(for 2C), 80.1 (for 2C), 70.5, 70.4, 53.1, 52.9, 42.1, 42.0, 38.8,
38.7, 37.2, 37.1, 26.0, 25.8, 21.1 (for 2C), 21.0, 20.8, Ϫ1.0 (for
2C). Anal. Calcd for C15H30O3Si: C, 62.63; H, 10.55. Found: C,
62.67; H, 10.47%.
(m, 5 H), 5.30 (dd, 1 H, J = 8.5, 6.0), 4.62–4.55 (m, 1 H), 2.65
(dt, 1 H, J = 11.7, 6.0), 2.55 (dt, 1 H, J = 11.7, 8.5), 1.17 (dd,
1 H, J = 14.1, 5.4), 0.93 (dd, 1 H, J = 14.1, 8.9), 0.08 (s, 9 H); 13
C
NMR δ 138.81, 128.66, 128.36, 126.83, 83.17, 80.05, 50.05,
20.90, Ϫ0.97. Anal. Calcd for C13H20O2Si: C, 66.05; H, 8.53.
Found: C, 65.87; H, 8.34%.
3-Methyl-3-phenyl-5-(trimethylsilylmethyl)-1,2-dioxaspiro[5.4]-
decane (22l)
3-Methyl-3-(4-acetoxyhept-6-enyl)-5-(trimethylsilylmethyl)-1,2-
dioxolane (26)
Compound 22l was isolated as a 1:1 mixture. Pure cis-22l and a
(1:1.5) mixture of cis/trans 22l were obtained by HPLC (2%
EA–hex). Rf = 0.33 (5% EA–hexane); 1H NMR (500 MHz)
δ 7.46–7.42 (m, 2 H), 7.32–7.38 (m, 2 H), 7.30–7.24 (m, 1 H),
4.43–4.36 (m, 1 H), 2.93 (dd, 1 H, J = 11.7, 6.4), 2.27 (dd, 1 H,
J = 11.7, 8.1), 1.68 (s, 3 H), 1.17 (dd, 1 H, J = 14.1, 5.6), 0.93
(dd, 1 H, J = 14.1, 9.3), 0.05 (s, 9 H); 13C NMR δ 144.80, 128.36,
127.18, 124.98, 86.79, 79.83, 56.00, 27.83, 21.62, Ϫ0.99. DEPT
135 NMR δ 128.36(ϩ), 127.18(ϩ), 124.98(ϩ), 79.83(ϩ),
56.00(Ϫ), 27.83(ϩ), 21.62(Ϫ), Ϫ0.99(ϩ). Anal. Calcd for
C14H22O2Si: C, 67.15; H, 8.86. Found: C, 67.22; H, 8.74%.
Acetylation of 25 (23 mg) with DMAP and acetic anhydride in
CH2Cl2 furnished, after standard work-up and flash chrom-
atography, 25 mg (92%) of 26 as a colorless oil which was
resolved by HPLC (3% EA–hex) into two cis dioxolanes cis-26a
(35%) and cis-26b (35%) as well as a mixture of two trans diox-
1
olanes trans-26ab (30%): cis-26a: Rf = 0.58 (20% EA–hex). H
NMR (500 MHz) δ 5.80–5.70 (m, 1 H), 5.11–5.04 (m, 2 H),
4.97–4.89 (m, 1 H), 4.40–4.32 (m, 1 H), 2.36 (dd, 1 H, J = 11.7,
6.8), 2.33–2.28 (m, 2 H), 1.89 (dd, 1 H, J = 11.7, 8.5), 2.03 (s, 3 H),
1.75–1.25 (m, 6 H), 1.26 (s, 3 H), 1.08 (dd, 1 H, J = 13.9, 5.0),
0.81 (dd, 1 H, J = 13.9, 9.5), 0.05 (s, 9 H); 13C NMR δ 170.8,
133.7(ϩ), 117.7(Ϫ), 85.7, 79.8(ϩ), 73.0(ϩ), 53.7(Ϫ), 40.3(Ϫ),
38.8(Ϫ), 33.9(Ϫ), 23.2(ϩ), 21.2(ϩ), 20.8(Ϫ), 20.3(Ϫ), Ϫ1.0(ϩ).
Calcd. for C17H32O4Si: C, 62.15; H, 9.82. Found: C, 62.19; H,
cis-3-Propyl-5-(trimethylsilylmethyl)-1,2-dioxaspiro[5.4]decane
(23j)
1
Rf = 0.45 (5% EA–hexane); H NMR (500 MHz) δ 4.35–4.23
(m, 2 H), 2.77 (dt, 1 H, J = 11.7, 6.9), 1.74 (ddd, 1 H, J = 11.7,
8.1, 6.5), 1.75–1.30 (m, 4 H), 1.11 (dd, 1 H, J = 14.1, 5.4), 0.93
1
9.70%. cis-26b: Rf = 0.56 (20% EA–hex). H NMR (500 MHz)
δ 5.80–5.70 (m, 1 H), 5.11–5.03 (m, 2 H), 4.95–4.88 (m, 1 H),
4.40–4.33 (m, 1 H), 2.35 (dd, 1 H, J = 11.7, 6.6), 2.37–2.25 (m,
2 H), 1.90 (dd, 1 H, J = 11.7, 8.3), 2.04 (s, 3 H), 1.75–1.67 (m,
1 H), 1.60–1.34 (m, 4 H), 1.43–1.34 (m, 1 H), 1.27 (s, 3 H), 1.07
(dd, 1 H, J = 13.7, 5.2), 0.81 (dd, 1 H, J = 13.7, 9.5), 0.05 (s, 9 H);
13C NMR δ 170.8, 133.7(ϩ), 117.7(Ϫ), 85.7, 79.8(ϩ), 73.2(ϩ),
53.5(Ϫ), 40.3(Ϫ), 38.6(Ϫ), 33.9(Ϫ), 23.4(ϩ), 21.3(ϩ), 20.8(Ϫ),
20.4(Ϫ), Ϫ1.0(ϩ). Anal. Calcd for C17H32O4Si: C, 62.2; H, 9.8.
Found: C, 62.6; H, 9.7%. Anal. Calcd for C17H32O4Si: C, 62.15;
H, 9.82. Found: C, 62.02; H, 9.67%. Spectral listings for trans-
26ab are included in supplementary material.
(t, 3 H, J = 6.9), 0.85 (dd, 1 H, J = 14.1, 9.3), 0.06 (s, 9 H); 13
C
NMR δ 81.42, 79.35, 48.33, 37.15, 21.02, 19.52, 13.99, Ϫ1.01.
Anal. Calcd for C10H22O2Si: C, 59.35; H, 10.96. Found: C,
59.47; H, 11.04%.
4-Methyl-4-phenylhepta-1,6-diene (24)
Rf = 0.75 in 5% (EA–hex); 1H NMR (500 MHz) δ 7.33–7.17 (m,
5 H), 5.63–5.47 (m, 2 H), 5.05–4.92 (m, 4 H), 2.52 (dd, 1 H,
J = 13.7, 6.6), 2.32 (dd, 2 H, J = 11.7, 6.6), 1.29 (s, 3 H); 13C
NMR δ 147.1, 135.1, 128.0, 126.4, 125.6, 117.2, 47.0, 24.2.
3-Methyl-3-(4-hydroxyhept-6-enyl)-5-(trimethylsilylmethyl)-1,2-
dioxolane (25)
3-Methyl-3-(4-oxohept-6-enyl)-5-(trimethylsilylmethyl)-1,2-
dioxolane (27)
To a Ϫ78 ЊC solution of 145 mg (1.1 mmol) of 14m in 20 mL of
Oxidation of 25 (23 mg) with PDC in CH2Cl2, furnished, after
3012
J. Chem. Soc., Perkin Trans. 1, 2000, 3006–3013