Int. J. Mol. Sci. 2017, 18, 2162
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13C NMR (75 MHz, CDCl3):
δ
141.5, 138.5, 132.9, 132.8, 130.6, 127.9, 126.2, 123.6, 71.2, 62.4, 32.2, 26.5,
19.4, 6.9, 5.1; HRMS (ESI) mass calcd for C19H34O2SiNa (M+ + Na) 341.1913, measured 341.1915.
[(20R,300R,500R)- and 20R,30R,500S)-30-[(500-(Triethylsilyl)oxy-500,600,700,800-tetrahydronaphthalen-100-
yl]-oxiran-2 -yl]-methanol (17). To a stirred suspension of the activated, powdered molecular sieves 4Å
(68 mg) in anhydrous methylene chloride (3.2 mL) and (-)-diisopropyl D-tartrate (17 µL, 0.12 mmol)
was added titanium(IV) isopropoxide (20
and solution of tert-butyl hydroperoxide (5.5 M in decane; 150 µL, 0.83 mmol) was slowly added.
µ
L, 0.07 mmol) at 0 ◦C. The mixture was cooled to −20 ◦C
After 45 min, a solution of alcohol 16 (220 mg, 0.69 mmol) in anhydrous methylene chloride (2.1 mL)
was transferred via cannula. The stirring was continued at
−
20 ◦C for 3 h, and then the reaction was
quenched with brine and extracted with methylene chloride. The organic phase was dried (MgSO4)
and concentrated. The residue was purified by column chromatography over silica using hexane/ethyl
acetate (8:2) to give colorless, oily epoxide 17 (185 mg, 79%). 1H NMR (300 MHz, CDCl3):
δ 0.71
(6H, q, J = 7.4 Hz, SiCH2CH3), 1.02 (9H, t, J =7.4 Hz, SiCH2CH3), 1.73–1.87 (2H, m, 700-H2), 1.90–2.14
(2H, m, 600-H2), 2.61-2.94 (2H, m, 800-H2), 3.03 (1H, dt, J = 3.7, 2.4 Hz, 20-H), 3.81 (1H, ddd, J = 12.7,
3.7, 1.4 Hz, one of 1-H2), 3.98–4.06 (2H, m, 30-H and one of 1-H2), 4.81 (1H, narr m, 500-H), 7.14 (1H, d,
00
00
00
J = 7.4 Hz, 4 -H), 7.19 (1H, t, J ~7.5 Hz, 3 -H), 7.36 (1H, m, 2 -H); 13C NMR (75 MHz, CDCl3):
δ 134.6,
128.1, 127.6, 125.9, 123.2, 123.1, 70.5, 61.3, 60.4, 53.7, 32.4, 25.7, 19.2, 6.9, 5.1; HRMS (ESI) mass calcd for
C19H30O3Na (M+ + Na) 357.1862, measured 357.1867.
0
0
0
0
0
0
0
0
(2S,3S,5 R)- and (2S,3S,5 S)-3-[(5 -(Triethylsilyl)oxy-5 ,6 ,7 ,8 -tetrahydronaphthalen-1 -yl]-butane-
1,2-diol (18). To a vigorously stirred suspension of CuCN (120 mg, 1.35 mmol) in anhydrous diethyl
◦
ether (3.6 mL) at
−
78 C, a solution of methyllithium (1.6 M in diethyl ether; 1.12 mL, 1.80 mmol) was
added. The mixture was stirred for 1 h and a solution of epoxide 17 (150 mg, 0.45 mmol) in anhydrous
diethyl ether (1.8 mL) was transferred via cannula. The cooling bath was removed and the mixture
was allowed to reach 0 ◦C during 3 h. Then, it was quenched with saturated NH4Cl and extracted
with ethyl acetate. The organic phase was dried (MgSO4) and evaporated. The residue was purified
by column chromatography over silica using hexane/ethyl acetate (9:1
≥
8:2) to give colorless, oily
1
diol 18 (127 mg, 80%). H NMR (300 MHz, CDCl3):
δ
0.71 (6H, q, J = 7.4 Hz, SiCH2CH3), 1.02 (9H, t,
0
J = 7.4 Hz, SiCH2CH3), 1.16 and 1.19 (1.5H and 1.5H, each d, J = 6.9 Hz, 4-H3), 1.67–1.84 (2H, m, 7 -H2),
1.91–2.10 (2H, m, 60-H2), 2.63–2.91 (2H, m, 80-H2), 3.22 (1H, m, 3-H), 3.60 (1H, dd, J = 11.2,06.3 Hz,0one
0
of 1-H2), 3.82 (2H, narr m, 2-H and one of 1-H2), 4.81 (1H, narr m, 5 -H), 7.14–7.24 (2H, m, 2 - and 4 -H),
0
7.33 (1H, t, J = 7.6 Hz, 3 -H); 13C NMR (75 MHz, CDCl3):
δ 141.2, 140.6, 139.5, 135.8, 135.6, 126.7, 126.3,
126.2, 124.7, 69.8, 69.7, 64.5, 36.3, 32.3, 29.7, 26.2, 19.4, 19.3, 17.9, 6.9, 5.1 Hz; HRMS (ESI) mass calcd for
C11H18O2Na (M+ + Na) 373.2175, measured 373.2175.
(2S,50R)- and (2S,50S)-2-[50-(Triethylsilyl)oxy-50,60,70,80-tetrahydronaphthalen-10-yl]propionaldehyde
(19). Sodium periodate (2.71 g, 12.65 mmol) and saturated NaHCO3 (1.3 mL) were added to a solution of
the diol 18 (738 mg, 2.11 mmol) in anhydrous methylene chloride (10.5 mL). The mixture was vigorously
stirred at room temperature for 1 h under argon. Then, reaction was diluted with saturated NaHCO3
and extracted with methylene chloride. The organic phase was dried (MgSO4) and evaporated.
The residue was purified by column chromatography over silica using hexane/ethyl acetate (95:5)
to afford aldehyde 19 (634 mg, 94%) as a colorless oil. 1H NMR (300 MHz, CDCl3):
δ 0.71 (6H, q,
J = 7.4 Hz, SiCH2CH3), 1.02 (9H, t, J = 7.4 Hz, SiCH2CH3), 1.37 (3H, d, J = 7.0 Hz, 3-H3), 1.73–1.86
(2H, m, 70-H2), 1.93–2.14 (2H, m, 60-H2), 2.62–2.87 (2H, m, 80-H2), 3.82 (1H, dq, J = 1.2, 7.0 Hz, 2-H),
4.83 (1H, t, J = 5.5 Hz, 50-H), 6.94 and 6.95 (0.5H and 0.5H, each d, J = 7.5 Hz, 20-H), 7.23 (1H, t,
J = 7.5 Hz, 30-H), 7.38 and 7.40 (0.5H and 0.5H, each d, J = 7.5 Hz, 40-H), 9.59 and 9.62 (0.5H and 0.5H,
each d, J = 1.2 Hz, 1-H); 13C NMR (75 MHz, CDCl3):
δ 201.2, 201.1, 141.1, 136.0, 135.4, 127.8, 127.6,
126.4, 126.4, 126.3, 69.5, 69.4, 48.6, 48.5, 32.3, 32.2, 26.3, 26.2, 19.4, 19.1, 14.5, 6.9, 5.1; HRMS (ESI) mass
calcd for C19H30O2Na (M+ + Na) 341.1913, measured 341.1907.
(2S,50R)- and (2S,50S)-2-[50-(Triethylsilyl)oxy-50,60,70,80-tetrahydronaphthalen-10-yl]-propan-1-ol
(
20). Sodium borohydride (290 mg, 0.91 mmol) was added to a solution of the aldehyde 19
(52 mg,
1.37 mmol) in methanol (11.5 mL) at 0 ◦C. The cooling bath was removed and the mixture was stirred