ENANTIOSELECTIVE OPENING OF EPOXIDE RING
3375
CHCl3 layers were dried over anhydrous Na2SO4. The solvent was concentrated, and
the crude product was purified by column chromatography over silica gel using
EtOAc=Petroleum ether=Et3N (2=12=1) to afford 7 (1.80 g, 72%) as yellow oil.
27
½aꢃD þ13.8 (c 1, EtOH); IR: n 3377, 3070, 3044, 2973, 2935, 1606, 1490, 1465,
1362, 1252, 1053 cmꢁ1
;
1H NMR (CDCl3): d (ppm) 0.96 (t, 6H, J ¼ 7.4 Hz),
1.45–1.60 (m, 4H), 2.63–2.68 (m, 2H), 3.52–3.84 (m, 5H), 3.66–13.71 (m, 3H),
3.86–4.06 (m, 4H), 7.15 (d, 2H, J ¼ 7.6 Hz), 7.62 (t, 1H, J ¼ 7.6 Hz). 13C NMR
(CDCl3): d (ppm) 10.62, 24.38, 51.48, 61.02, 62.86, 120.81, 137.44, 159.0. Anal. calcd.
for: C15H27O2N3: C, 64.05; H, 9.61; N, 14.95. Found: C, 64.00; H, 9.78, N, 14.85.
(R,R)-Bis(2,6-pyridyldimethyl)-2-[N-benzyl]-butan-1-ol 8
(R)-N-Benzyl-2-amino-1-butanol (4.81 g, 26.80 mmol) and 2,6-pyridinedi-
methyl ditosylate (3.00 g, 6.71 mmol) were stirred at 100 ꢀC for 12 h under argon.
Then the mixture was cooled, and 100 mL CHCl3 were added to the mixture and
refluxed for 2 h. The organic phase was separated from the solid phase. The remain-
ing solid was re-extracted with CHCl3 (3 ꢂ 50 mL). The combined CHCl3 layers were
dried over anhydrous Na2SO4. The solvent was concentrated, and the crude product
was purified by column chromatography over silica gel using toluene=EtOAc=Et3N
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(15=1.5=0.5) to afford 8 (1.5 g, 49%) as yellow oil. ½aꢃD ꢁ10.8o(c 1, EtOH); IR: n
3288, 3072, 3031: 2978, 2935, 1606, 1496, 1458, 1162, 1079 cmꢁ1; 1H NMR (CDCl3):
d (ppm) 0.95 (t, 6H, J ¼ 7.6 Hz), 1.28–1.35 (m, 2H), 1.74–1.81 (m, 2H), 2.79–2.86
(m, 2H), 3.53–3.74 (m, 8H), 3.86 (d, 2H, J ¼ 13.6 Hz), 3.98 (d, 2H, J ¼ 14.0 Hz),
5.07 (bs, 2H), 6.98 (d, 2H, J ¼ 7.6 Hz) 7.16–7.32 (m , 10H), 7.46 (t, 1H, J ¼ 7.6 Hz).
13C NMR (CDCl3): d (ppm) 11.85, 19.34, 54.48, 54.91, 61.64, 63.26, 121.21, 126.93,
128.20, 128.92, 136.89, 139.62, 159.61. Anal. calcd. for C29H39O2N3: C, 75.48; H,
8.46; N, 9.11. Found: C, 75.60; H, 8.58; N, 9.12.
(R,R)-Bis(a,a’-dibromo-m-xylene)-2-aminobutan-1-ol 9
Compound 9 was prepared as described for 7 starting from (R)-2-amino-1-
butanol (10.79 g, 121.30 mmol), a,a0-dibromo-m-xylene (4.0 g, 15.20 mmol), and
Na2CO3 (3.2 g, 30.18 mmol). The crude product was purified by column chromato-
graphy over silica gel using n-hexane=EtOH=Et3N (6=2=1) to afford 9 (3.2 g, 75%) as
27
yellow oil. ½aꢃD ꢁ9.6o (c 5, EtOH); IR: n 3240, 2962, 2930, 2870, 1601, 1575, 1463,
1158, 1053, 802 cmꢁ1; 1H NMR (CDCl3): d (ppm) 0.93 (t, 6H, J ¼ 7.6 Hz), 1.25–1.29
(m, 1H), 1.44–1.58 (m, 3H), 1.74–1.79 (m, 1H), 2.59–2.71 (m, 3H), 3.32–3.36 (m,
4H), 3.44–3.49 (m, 2H), 3.65–3.81 (m,4H), 7.16–7.31 (m, 4H). 13C NMR (CDCl3):
d (ppm) 10.39, 24.21, 51.01, 59.86, 62.67, 126.88, 127.71, 127.87, 128.60. Anal. calcd.
for C16H28O2N2: C, 68.57; H, 10.00; N, 10.00. Found: C, 68.63; H, 10.15; N, 10.08.
(R,R)-Bis(a,a’-dibromo-m-xylene)-2-[N-benzyl]-butan-1-ol 10
Compound 10 was prepared as described for 8 starting from (R)-N-
benzyl-2-amino-1-butanol (8.14 g, 45.40 mmol), a,a0-dibromo-m-xylene (3.00 g,
11.30 mmol), and Na2CO3 (2.39 g, 22.55 mmol). The crude product was purified by
column chromatography over silica gel using toluene=EtOAc=Et3N (13=0.5=0.5) to