ACCEPTED MANUSCRIPT
Na2SO4 and concentrated in vacuo. The residue was purified using flash column chromatography
(0 - 8% ethyl acetate : petroleum ether) to afford mono TBS ether 15 (518 mg, 98%) as a
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colorless oil; Rf (5% ethyl acetate : hexane) = 0.35. [α]D = +14.3 (c 1.00, CHCl3); νmax (liquid
1
film) 3610, 3580-3400 (br), 1625, 1605, 1530, 1480, 1260, 1120, 1090, 1050, 850, 795 cm-1. H
NMR (300 MHz, CDCl3)
δ 7.26 (d, J = 8.5 Hz, 2H), 6.88 (d, J = 8.5 Hz, 2H), 5.61 (dt, J = 11.0,
7.3 Hz, 1H), 5.33 (dd, J = 11.0, 9.5 Hz, 1H), 4.51 (d, J = 11.3 Hz, AB, 1H), 4.26 (d, J = 11.3 Hz,
AB, 1H), 4.12-4.02 (m, 1H), 3.82 (s, 3H), 3.69-3.59 (m, 2H), 3.40 (dd, J = 8.5, 10.4 Hz, 1H),
2.17-1.96 (m, 2H), 1.74-1.11 (m, 14H), 0.92 (s, 9H), 0.89 (t, J = 7.0 Hz, 3H), 0.09 (s, 6H) ppm.
13C NMR (75 MHz, CDCl3)
δ 159.1, 132.9, 131.6, 131.2, 129.3 (×2), 113.8 (×2), 73.9, 71.7,
69.5, 67.3, 55.4, 35.9, 32.5, 32.0, 29.4, 27.9, 26.0 (×3), 25.9, 25.5, 22.7, 18.4, 14.2, -5.2, -5.3
ppm. Elemental analysis calcd (%) for C28H50O4Si: C 70.24, H 10.53; found: C 70.01, H 10.54.
4.2.12.(R)-5-((R)-Z-6-((4-methoxybenzyl)oxy)dodec-4-en-1-yl)-2,2,8,8,9,9-hexamethyl-3,3-
diphenyl-4,7-dioxa-3,8-disiladecane (16).
A solution of mono TBS ether 15 (518 mg, 1.1 mmol), imidazole (220 mg, 3.2 mmol) in dry
DMF (5.4 mL) was cooled to 0 °C. TBDPS-Cl (0.42 mL, 1.6 mmol) was added dropwise at 0 °C.
After complete addition, the reaction mixture was stirred at room temperature under N2
atmosphere for 12 h. TLC showed partial completion of reaction, thus another (302 mg, 1.1
mmol of TBDPS-Cl was added and stirred for further 8 h. The reaction was quenched by addition
of ice; the aqueous layer was extracted with diethyl ether (3 × 50 mL), then the combined organic
extracts were washed with brine (30 mL), dried over anhydrous Na2SO4 and concentrated in
vacuo. The residue was purified using flash column chromatography with 0-3% ethyl acetate:
petroleum ether) to afford bis-silyl ether 16 (773 mg, 98%) as a yellow oil; Rf (2% ethyl acetate :
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hexane) = 0.47. [α]D = +5.5 (c 1.2, CHCl3). νmax (liquid film) 3100, 1630, 1520, 1480, 1265,
1
1120, 850, 720 cm-1. H NMR (300 MHz, CDCl3)
δ = 7.76-7.65 (m, 4H), 7.47-7.31 (m, 6H),
7.24 (d, J = 8.5 Hz, 2H), 6.87 (d, J = 8.5 Hz, 2H), 5.51 (dt, J = 11.0, 7.0 Hz, 1H), 5.27 (dd, J =
11.0, 9.5 Hz, 1H), 4.48 (d, J = 11.6 Hz, AB, 1H), 4.21 (d, J = 11.6 Hz, AB, 1H), 4.011-4.01 (m,
1H), 3.81 (s, 3H), 3.85-3.71 (m, 1H), 3.53-3.38 (m, 2H), 2.00-1.84 (m, 2H), 1.65-1.20 (m, 14H),
1.06 (s, 9H), 0.89 (t, J = 7.0 Hz, 3H), 0.83 (s, 9H), 0.06 (s, 3H), 0.01 (s, 3H) ppm. 13C NMR (75
MHz, CDCl3)
δ = 159.1, 136.0 (×6), 134.6, 134.5, 133.3, 131.3, 129.7, 129.4, 127.6 (×5), 113.7
(×2), 74.1, 73.6, 69.6, 66.3, 55.4, 35.9, 33.6, 32.0, 29.5, 28.1, 27.2 (×3), 26.0 (×3), 25.5, 24.8,
22.8, 19.5, 18.4, 14.3, -5.3 (×2) ppm. Elemental analysis calcd (%) for C44H68O4Si2: C 73.69, H
9.56: found: C 73.50, H 9.55.
16