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The Journal of Organic Chemistry
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333 [MH+ ꢀ H2O, 51%], 219 (98), 201 (100), 133 (23); HRMS (FIꢀhybrid of quadrupole and TOF) m/z: [M]+ Calcd
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for C21H38O2Si 350.2641; Found 350.2622.
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Mosher’s esters (19a, 19b, 21a, and 21b)
(+)ꢀMTPACl (5 drops) was added to a stirred solution of 18 (1.2 mg, 0.034 mmol) in dry pyridine (1 mL) at room
temperature, and stirring was continued for 14 h. Saturated NaHCO3 aq was added, and the mixture was extracted
with Et2O and dried. Evaporation of the solvent followed by silica gel column chromatography (hexaneꢀEtOAc
19:1) afforded 19a (1.4 mg, 72%) as a colorless oil. Similarly, 18 (1.3 mg, 0.0037 mmol) was treated with
(–)ꢀMTPACl to afford 19b (1.4 mg, 67%) as a colorless oil; 20 (1.8 mg, 0.0051 mmol) afforded 21a (2.5 mg, 86%)
as a colorless oil; 20 (1.8 mg, 0.0051 mmol) afforded 21b (3.0 mg, quant) as a colorless oil.
19a: 1H NMR δ 0.07 (s, 3H), 0.09 (s, 3H), 0.90 (s, 9H), 1.51ꢀ1.59 (m, 1H), 1.61 (s, 3H), 1.69 (s, 3H), 1.70 (s, 3H),
1.84ꢀ2.05 (m, 2H), 2.15ꢀ2.30 (m, 2H), 2.32ꢀ2.42 (m, 1H), 2.48 (dt, J = 15.0, 8.5 Hz, 1H), 3.54 (s, 3H), 4.16ꢀ4.27 (m,
1H), 4.95 (s, 1H), 4.99 (s, 1H), 5.05ꢀ5.14 (m, 1H), 5.35 (dd, J = 5.0, 9.0 Hz, 1H), 5.40ꢀ5.48 (m, 1H), 7.34ꢀ7.43 (m,
3H), 7.47ꢀ7.55 (m, 2H).
19b: 1H NMR δ 0.04 (s, 3H), 0.07 (s, 3H), 0.90 (s, 9H), 1.53 (s, 3H), 1.55ꢀ1.62 (m, 2H), 1.63 (s, 3H), 1.67ꢀ1.71 (m,
3H), 1.92 (t sext, J = 14.0, 2.5 Hz, 1H), 1.99 (ddt, J = 6.0, 12.5, 2.5 Hz, 1H), 2.13ꢀ2.22 (m, 1H), 2.24ꢀ2.37 (m, 1H),
2.43 (dt, J = 15.0, 7.5 Hz, 1H), 3.52 (s, 3H), 4.16ꢀ4.24 (m, 1H), 4.92ꢀ4.98 (m, 1H), 5.05 (s, 1H), 5.16 (s, 1H), 5.41
(dd, J = 5.5, 8.0 Hz, 1H), 5.42ꢀ5.47 (m, 1H), 7.34ꢀ7.42 (m, 3H), 7.47ꢀ7.52 (m, 2H).
21a: 1H NMR δ 0.07 (s, 3H), 0.09 (s, 3H), 0.90 (s, 9H), 1.51ꢀ1.57 (m, 1H), 1.53 (s, 3H), 1.63 (s, 3H), 1.67ꢀ1.70 (m,
3H), 1.84ꢀ2.12 (m, 3H), 2.24ꢀ2.39 (m, 2H), 2.42 (dt, J = 15.0, 8.0 Hz, 1H), 3.51 (s, 3H), 4.16ꢀ4.25 (m, 1H),
4.92ꢀ5.00 (m, 1H), 5.06 (s, 1H), 5.18 (s, 1H), 5.38ꢀ5.44 (m, 1H), 5.42 (dd, J = 5.5, 8.5 Hz, 1H), 7.33ꢀ7.42 (m, 3H),
7.47ꢀ7.54 (m, 2H).
21b: 1H NMR δ 0.07 (s, 3H), 0.09 (s, 3H), 0.90 (s, 9H), 1.42ꢀ1.55 (m, 1H), 1.61 (s, 3H), 1.66ꢀ1.69 (m, 3H), 1.70 (s,
3H), 1.77ꢀ1.95 (m, 2H), 2.03 (ddt, J = 6.0, 12.0, 2.0 Hz, 1H), 2.14ꢀ2.24 (m, 1H), 2.35ꢀ2.43 (m, 1H), 2.48 (dt, J =
15.0, 8.0 Hz, 1H), 3.55 (s, 3H), 4.10ꢀ4.19 (m, 1H), 4.97 (s, 1H), 5.04 (s, 1H), 5.06ꢀ5.11 (m, 1H), 5.34ꢀ5.39 (m, 1H),
5.39 (dd, J = 5.0, 8.5 Hz, 1H), 7.33ꢀ7.41 (m, 3H), 7.48ꢀ7.53 (m, 2H).
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(3S)-2-((1R,5R)-5-Hydroxy-4-methylcyclohex-3-en-1-yl)-6-methylhepta-1,5-dien-3-ol
(3R)-2-((1R,5R)-5-hydroxy-4-methylcyclohex-3-en-1-yl)-6-methylhepta-1,5-dien-3-ol (24)
(22)
and
A solution of TBAF (1 M in THF, 0.84 mL, 0.84 mmol) was added to a stirred solution of 18 (97.3 mg, 0.28 mmol)
in THF (9 mL) and stirring was maintained at room temperature for 1 day. A saturated NH4Cl aq was added, and
the mixture was extracted with EtOAc and dried. Evaporation of the solvent followed by silica gel column
chromatography (hexaneꢀEtOAc 8:2) afforded 22 (59.2 mg, 89%) as a colorless oil. By the same procedure, 20
(162.3 mg, 0.46 mmol) afforded 24 (106.7 mg, 98%) as a colorless oil.
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22: [α]D –24.5 (c 0.139, MeOH); IR (neat/NaCl) 3348 (OH), 1645 (C=C), 1450, 1036, 756 cmꢀ1; H NMR δ
1.54ꢀ1.82 (m, 3H), 1.65 (s, 3H), 1.74 (s, 3H), 1.77 (br s, 3H), 1.88ꢀ1.99 (m, 1H), 2.11ꢀ2.38 (m, 5H), 4.09ꢀ4.14 (m,
1H), 4.19ꢀ4.25 (m, 1H), 4.96 (s, 1H), 5.10ꢀ5.16 (m, 1H), 5.14 (s, 1H), 5.48ꢀ5.52 (m, 1H); 13C NMR δ 18.1, 18.9,
25.9, 33.0, 35.2, 35.6, 39.2, 71.0, 73.7, 108.7, 119.8, 123.9, 135.5, 136.2, 155.4; MS (FI) m/z: 218 [M+ ꢀ H2O,
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