UPDATES
Tetsuhiro Nemoto et al.
910 mg (99%). IR (ATR): n=2928, 1731, 1509, 1461, 1362,
1.30–1.90 (m, 10H), 2.21 (d, J=7.2 Hz, 2H), 2.64–2.73 (m,
2H), 2.93–3.01 (m, 1H), 3.36–3.52 (m, 4H), 3.78–3.90 (m,
1H), 3.80 (s, 3H), 4.05–4.18 (m, 2H), 4.45 (s, 2H), 5.68 (t,
J=2.2 Hz, 1H), 6.84 (d, J=8.8 Hz, 2H), 7.17–7.37 (m, 7H);
13C NMR (CDCl3): d=14.1, 19.1, 23.9, 26.0, 28.7, 31.0, 36.9,
43.4, 51.2, 51.6, 54.9, 55.2, 60.5, 70.3, 72.6, 113.8 (2C), 118.5
(q, J=318 Hz), 121.7, 127.5 (2C), 127.6 (2C), 128.3 (2C),
128.4, 129.0, 131.2, 138.6, 148.5, 158.6, 172.2; HR-MS
[(+)-ESI-TOF]: m/z=640.2559, calcd. for C32H41F3NO7S+
(M+H+): 640.2550; [a]D22: +35.5 (c 0.96, CHCl3, 95% ee).
1
1247, 1176, 1098, 1036 cmÀ1; H NMR (CDCl3): d=0.15 (s,
6H), 0.96 (s, 9H), 1.23 (t, J=6.8 Hz, 3H), 1.30–1.78 (m,
12H), 1.90–2.10 (m, 1H), 2.19 (dd, J=5.6, 14.4 Hz, 1H),
2.38 (dd, J=10.0, 14.4 Hz, 1H), 2.85–2.94 (m, 2H), 3.33 (d,
J=14.4 Hz, 1H), 3.48 (t, J=6.4 Hz, 2H), 3.55–3.66 (m, 2H),
3.80 (s, 3H), 4.05–4.14 (m, 2H), 4.49 (s, 2H), 6.80–6.88 (m,
2H), 7.20–7.36 (m, 7H); 13C NMR (CDCl3): d À3.6 (2C),
14.3, 19.8, 20.9, 25.6, 25.8 (3C), 27.0, 29.8, 30.8, 32.7, 33.7,
36.7, 49.6, 52.6, 55.1, 55.2, 60.1, 70.2, 72.9, 113.6 (2C), 117.6,
127.5, 127.7 (2C), 128.3 (2C), 129.3 (2C), 132.9, 138.6, 139.7,
158.3, 172.8; HR-MS [(+)-ESI-TOF]: m/z=622.3929, calcd.
for C37H56NO5Si+ (M+H+): 622.3922; [a]2D5: À16.6 (c 0.75,
CHCl3, 95% ee).
Ethyl 2-{(2R,4aR,5R,8aS)-2-{3-[(tert-butyldiphenyl-
silyl)oxy]propyl]decahydroquinolin-5-yl}acetate (13)
A suspension of 11 (149 mg, 0.233 mmol) and Pd(OH)2/C
(74.6 mg, 50 wt% Pd on carbon) in MeOH (4.70 mL) and
2M solution of HCl in MeOH (0.230 mL) was stirred under
H2 atmosphere at room temperature. After 8 h, the resulting
mixture was filtered through a short pad of celite, and the
filtrate was evaporated under reduced pressure. The crude
12 was used for the next reaction without further purifica-
tion. To a stirred solution of crude 12 (0.233 mmol), imida-
zole (47.6 mg, 0.699 mmol) and DMAP (5.7 mg,
0.0466 mmol) in CH2Cl2 (0.470 mL) was added TBDPSCl
(0.180 mL, 0.699 mmol), and the reaction mixture was
stirred at room temperature. After 24 h, the reaction was
quenched with H2O, and the resulting mixture was extracted
with CH2Cl2 3 times. The combined organic layers were
washed with brine, and then dried over Na2SO4. After con-
centration under vacuum, the obtained crude residue was
purified by flash column chromatography (CH2Cl2/MeOH=
20/1 to 5/1) to give 13 as a colorless oil; yield: 119.2 mg
(97%). IR (ATR): n=2932, 1732, 1428, 1374, 1236, 1167,
Ethyl 2-{(2S,4aR,5R,8aS)-2-[3-(Benzyloxy)propyl]-1-
(4-methoxybenzyl)-4-oxodecahydroquinolin-5-yl}-
acetate (9)
To a stirred solution of 8 (60.1 mg, 0.0965 mmol) in wet
THF (THF/H2O=100/1, 1.9 mL) was added TBAF
(0.193 mL, 1M in THF, 0.193 mmol) and the resulting solu-
tion was stirred at room temperature for 2 h. The reaction
mixture was concentrated, and the obtained crude residue
was purified by flash column chromatography (hexane/
EtOAc=3/1) to give 9 as a pale yellow oil; yield: 31.7 mg
(65%) and 10 as a pale yellow oil; yield: yield: 8.4 mg
(17%).
Compound 9: IR (ATR): n=2935, 1702, 1611, 1509, 1456,
1367, 1246, 1172, 1100, 1031 cmÀ1 1H NMR (CDCl3): d=
;
1.25 (t, J=7.2 Hz, 3H), 1.20–1.80 (m, 10H), 2.11 (dd, J=0.8,
7.6 Hz, 2H), 2.25–2.35 (m, 2H), 2.58–2.68 (m, 1H), 2.85–
2.94 (m, 1H), 3.04–3.11 (m, 1H), 3.20–3.28 (m, 1H), 3.40–
3.48 (m, 2H), 3.67–3.85 (m, 2H), 3.81 (s, 3H), 4.11 (q, J=
7.2 Hz, 2H), 4.45 (d, J=12.0 Hz, 1H), 4.49 (d, J=12.0 Hz,
1H), 6.80–6.91 (m, 2H), 7.22–7.35 (m, 7H); 13C NMR
(CDCl3): d=14.2, 20.5, 26.0, 27.2, 27.5, 28.4, 29.4, 37.1, 44.3,
48.6, 55.1, 55.3, 55.6, 60.2, 69.7, 72.8, 113.6, 113.7 (2C),
127.4, 127.5 (2C), 128.3 (2C), 129.3 (2C), 131.6, 138.4, 158.5,
172.7, 210.1; HR-MS [(+)-ESI-TOF]: m/z=508.3057, calcd.
1108, 1028, 822 cmÀ1 1H NMR (CDCl3): d=1.04 (s, 9H),
;
1.19–1.74 (m, 14H), 1.80–1.92 (m, 3H), 1.95–2.04 (m, 1H),
2.15–2.24 (m, 1H), 2.35–2.41 (m, 2H), 2.98–3.13 (m, 1H),
3.36–3.46 (m, 1H), 3.60–3.69 (m, 3H), 4.10 (q, J=7.2 Hz,
2H), 7.34–7.45 (m, 6H), 7.60–7.67 (m, 4H); 13C NMR
(CDCl3): d=14.2, 19.1, 19.7, 23.5, 26.8 (3C), 28.1, 29.7, 29.8,
34.8, 36.9, 37.1, 37.2, 50.5, 51.6, 51.6, 60.4, 63.4, 127.7 (4C),
129.6 (2C), 133.5, 133.6, 135.5 (4C), 172.5; HR-MS
[(+)-ESI-TOF]: m/z=522.3412, calcd. for C32H48NO3Si+
(M+H+): 522.3398; [a]D22: À4.07 (c 1.03, CHCl3, 95% ee).
+
for C31H42NO5 (M+H+): 508.3057; [a]2D5: À40.6 (c 1.10,
CHCl3, 95% ee).
Ethyl 2-{(2S,4aR,5R,8aS)-2-[3-(Benzyloxy)propyl]-1-
(4-methoxybenzyl)-4-{[(trifluoromethyl)sulfonyl]oxy}-
1,2,4a,5,6,7,8,8a-octahydroquinolin-5-yl]acetate (11)
tert-Butyl (2R,4aR,5R,8aS)-2-{3-[(tert-Butyldi-
phenylsilyl)oxy]propyl}-5-(2-ethoxy-2-oxoethyl)octa-
hydroquinoline-1(2H)-carboxylate (14)
To a stirred solution of 9 (740 mg, 1.16 mmol) in THF
(11.5 mL) at À788C was added t-BuOK (519 mg,
4.63 mmol), and the reaction mixture was stirred at the
same temperature. After 1 h, PhNTf2 (1.65 g, 4.63 mmol)
was added to the solution, and the resulting mixture was
stirred at the same temperature for 30 min, and then gradu-
ally warmed up to room temperature. The reaction was
quenched with saturated aqueous NH4Cl solution and ex-
tracted with Et2O. The combined organic layers were
washed with brine and dried over Na2SO4. After concentra-
tion under vacuum, the obtained crude residue was purified
by flash column chromatography (hexane/EtOAc=20/1 to
5/1) to give 11 as a pale yellow oil; yield: 709 mg (96%). IR
(ATR): n=2939, 1732, 1509, 1416, 1245, 1207, 1141, 1033,
A suspension of 13 (464 mg, 0.889 mmol), Boc2O (3.88 g,
17.8 mmol), and K2CO3 (61.4 mg, 0.444 mmol) in CH3CN
(8.90 mL) was refluxed for 24 h. After the reaction was
cooled down to room temperature, the solvent was evapo-
rated. The obtained crude residue was purified by flash
column chromatography (hexane/EtOAc=20/1 to 10/1) to
give 14 as a colorless oil; yield: 341 mg (61%). IR (ATR):
n=2932, 1732, 1682, 1472, 1364, 1264, 1170, 1105, 822 cmÀ1
;
1H NMR (CDCl3): d=1.04 (s, 9H), 1.23 (t, J=7.2 Hz, 3H),
1.42 (s, 9H), 1.18–2.00 (m, 14H), 2.04–2.13 (m, 1H), 2.33–
2.53 (m, 2H), 3.61–3.72 (m, 4H), 3.77–3.85 (m, 1H), 4.10 (q,
J=7.2 Hz, 2H), 7.3–7.42 (m, 6H), 7.65 (d, J=6.8 Hz, 4H);
13C NMR (CDCl3): d=14.3, 19.2, 20.1, 23.1, 24.2, 27.0 (3C),
28.5 (3C), 28.6, 29.4, 30.5, 31.9, 35.5, 35.6, 37.9, 50.5, 51.2,
857 cmÀ1
;
1H NMR (CDCl3): d=1.24 (t, J=7.2 Hz, 3H),
2552
ꢁ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2015, 357, 2547 – 2555