S. Yamazaki et al. / Tetrahedron: Asymmetry 20 (2009) 1224–1234
1231
2H), 8.67 (br s, 1H); 13C NMR (100.6 MHz, CDCl3) d (ppm) 13.99 (q),
14.06 (q), 27.88 (q), 45.25 (d), 54.95 (d), 61.87 (t), 61.99 (t), 82.26
(s), 106.02 (d), 115.01 (d), 124.86 (s), 124.96 (d), 125.46 (d), 125.90
(s), 128.63 (d), 135.73 (s), 167.73 (s), 168.10 (s), 170.12 (s); IR
(neat) 3373, 2981, 1733, 1605, 1370, 1152, 1033 cmꢀ1; MS (EI)
m/z 415 (M+, 13), 315 (21), 314 (38), 313 (38), 173 (67), 105
(100%); HRMS M+ 415.1997 (calcd for C23H29NO6 415.1995).
Compound 4i-2 (Table 1, entry 18) (Rf = 0.5 (hexane–
ether = 1:1)): pale yellow crystals; mp = 115–119 °C; HPLC (CHIR-
ALPAK AD-H, hexane–iPrOH = 7:1) major peak tR1 4.4 min, minor
167.92 (s), 172.10 (s); IR (neat) 3389, 2982, 1733, 1369, 1301,
1174, 1030 cmꢀ1; MS (EI) m/z 339 (M+, 98), 266 (100%); HRMS
M+ 339.1681 (calcd for C17H25NO6 339.1682).
Compound 5c (Table 2, entry 4) (Rf = 0.4 (hexane–ether = 1:1)):
yellow oil; HPLC (CHIRALPAK AD-H, hexane–iPrOH = 9:1) major
peak tR1 17.8 min, minor peak tR2 19.9 min, 48% ee; ½a D23
¼ ꢀ38 (c
ꢃ
0.54, CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.10 (t, J = 7.1 Hz,
3H), 1.20 (t, J = 7.1 Hz, 3H), 1.97 (s, 3H), 2.14 (d, J = 0.7 Hz, 3H),
3.96–4.22 (m, 4H), 4.11 (d, J = 10.5 Hz, 1H), 4.42 (d, J = 10.5 Hz,
1H), 5.03 (d, J = 12.7 Hz, 1H), 5.14 (d, J = 12.7 Hz, 1H), 5.60 (d,
J = 2.7 Hz, 1H), 7.10 (d-like, J = 8.5 Hz, 1H), 7.43 (d-like, J = 8.5 Hz,
1H), 7.93 (br s, 1H); 13C NMR (100.6 MHz, CDCl3) d (ppm) 10.79
(q), 13.04 (q), 13.84 (q), 13.98 (q), 42.13 (d), 54.51 (d), 61.71 (t),
61.99 (t), 66.15 (t), 108.27 (d), 117.39 (s), 118.17 (s), 122.13 (s),
127.78 (s), 129.40 (d), 131.62 (d), 134.78 (s), 167.56 (s), 167.83
(s), 171.71 (s); IR (neat) 3390, 2981, 2937, 1732, 1597, 1489, 1370,
1294, 1159 cmꢀ1; MS (EI) m/z 481 (M+, 20), 479 (M+, 20), 310 (34),
266 (100%); HRMS M+ 479.0929 (calcd for C22H2679BrNO6
479.0944), 481.0909 (calcd for C22H2681BrNO6 481.0909); Anal.
Calcd for C22H26BrNO6: C, 55.01; H, 5.46; N, 2.92. Found: C, 54.79;
H, 5.26; N, 2.89.
peak tR2 8.4 min, 50% ee; ½a D22
ꢃ
¼ ꢀ77 (c 1.23, CHCl3); 1H NMR
(400 MHz, CDCl3)
d (ppm) 1.03 (t, J = 7.1 Hz, 3H), 1.21 (t,
J = 7.1 Hz, 3H), 1.44 (s, 9H), 3.84–3.92 (m, 1H), 3.99–4.18 (m, 3H),
4.09 (d, J = 9.5 Hz, 1H), 4.53 (d, J = 9.5 Hz, 1H), 6.19 (t, J = 2.7 Hz,
1H), 6.77 (t, J = 2.7 Hz, 1H), 7.32–7.40 (m, 4H), 8.97 (br s, 1H);
13C NMR (100.6 MHz, CDCl3) d (ppm) 13.75 (q), 13.91 (q), 27.92
(q), 42.74 (d), 54.72 (d), 61.81 (t), 61.95 (t), 82.53 (s), 109.00 (d),
118.56 (d), 120.48 (s), 123.70 (s), 128.65 (d), 129.69 (d), 131.76
(s), 134.94 (s), 167.63 (s), 168.06 (s), 170.43 (s); IR (KBr) 3396,
3354, 2986, 1746, 1732, 1717, 1700, 1502, 1369, 1313,
1143 cmꢀ1; MS (EI) m/z 451 (M+, 20), 449 (M+, 53), 348 (100%);
HRMS M+ 449.1606 (calcd for C23H2835ClNO6 449.1605), 451.1606
(calcd for C23H2837ClNO6 451.1576); Anal. Calcd for C23H28ClNO6:
C, 61.40; H, 6.27; N, 3.11. Found: C, 60.95; H, 6.20; N, 3.05.
Compound 5d (Table 2, entry 5) (Rf = 0.2 (CH2Cl2–ether = 9:1)):
brown solid; HPLC (CHIRALPAK AD-H, hexane–iPrOH = 19:1) major
peak tR1 20.1 min, minor peak tR2 26.0 min, 71% ee; ½a D27
¼ ꢀ118 (c
ꢃ
Compound 4i-5 (Table 1, entry 18) (Rf = 0.3 (hexane–ether = 1:
1.08, CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.06 (t, J = 7.1 Hz,
3H), 1.26 (t, J = 7.1 Hz, 3H), 1.20–1.30 (m, 1H), 1.40–1.70 (m, 5H),
1.96 (s, 3H), 2.14 (d, J = 0.5 Hz, 3H), 3.37–3.48 (m, 2H), 3.54–3.62
(m, 2H), 3.88–3.96 (m, 2H), 3.98–4.06 (m, 2H), 4.10–4.26 (m,
4H), 4.29 (d, J = 11.0 Hz, 1H), 4.64 (d, J = 11.0 Hz, 1H), 5.54 (d,
J = 2.7 Hz, 1H), 8.00 (br s, 1H); 13C NMR (100.6 MHz, CDCl3) d
(ppm) 10.73 (q), 13.02 (q), 13.83 (q), 14.06 (q), 24.61 (t), 25.66
(t), 25.99 (t), 38.89 (d), 43.66 (t), 47.12 (t), 55.56 (d), 61.40 (t),
61.60 (t), 107.70 (d), 116.07 (s), 118.53 (s), 127.74 (s), 168.30 (s),
168.45 (s), 169.41 (s); IR (KBr) 3301, 2938, 1751, 1620,
1267 cmꢀ1; MS (EI) m/z 378 (M+, 19), 266 (100%); HRMS M+
378.2145 (calcd for C20H30N2O5 378.2155); Anal. Calcd for
C20H30N2O5: C, 63.47; H, 7.99; N, 7.40. Found: C, 63.14; H, 7.90;
N, 7.30.
1)): yellow oil; HPLC (CHIRALPAK AD-H, hexane–iPrOH = 7:3) ma-
jor peak tR1 11.2 min, minor peak tR2 17.5 min, 28% ee; ½a D26
¼ ꢀ13
ꢃ
(c 0.20, CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.15 (t,
J = 7.1 Hz, 3H), 1.24 (t, J = 7.1 Hz, 3H), 1.43 (s, 9H), 4.10 (d,
J = 10.0 Hz, 1H), 4.11 (q, J = 7.1 Hz, 2H), 4.15–4.21 (m, 2H), 4.30
(d, J = 10.0 Hz, 1H), 6.29 (dd, J = 2.2, 1.8 Hz, 1H), 6.98 (dd, J = 2.7,
1.8 Hz, 1H), 7.25–7.28 (m, 2H), 7.36–7.39 (m, 2H), 8.69 (br s,
1H); 13C NMR (100.6 MHz, CDCl3) d (ppm) 14.02 (q), 14.08 (q),
27.90 (q), 45.17 (d), 54.94 (d), 61.91 (t), 62.04 (t), 82.40 (s),
106.05 (d), 115.16 (d), 123.78 (s), 126.17 (d), 126.23 (s), 128.71
(d), 130.90 (s), 134.28 (s), 167.68 (s), 168.15 (s), 170.01 (s); IR
(neat) 3375, 2981, 1733, 1520, 1492, 1033 cmꢀ1; MS (EI) m/z 451
(M+, 8), 449 (M+, 23), 347 (67), 139 (92), 57 (100%); HRMS M+
449.1602 (calcd for C23H2835ClNO6 449.1605), 451.1578 (calcd for
C23H2837ClNO6 451.1576).
Compound 5e (Table 2, entry 7) (Rf = 0.2 (CH2Cl2)): yellow crys-
tals, HPLC (CHIRALPAK AD-H, hexane–EtOH = 7:3) major peak tR1
Compound 4jz (1-tert-Butyl 2,2-dibenzyl 1-(3,5-dimethyl-1H-
pyrrol-2-yl)ethane-1,2,2-tricarboxylate) Rf = 0.6 (hexane–ether =
1:1): brownoil; HPLC (CHIRALPAK AS-H, hexane–iPrOH = 9:1) major
6.0 min, minor peak tR2 12.3 min, 41% ee; ½a D22
¼ ꢀ83 (c 1.68,
ꢃ
CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.10 (t, J = 7.1 Hz, 3H),
1.18 (t, J = 7.1 Hz, 3H), 2.06 (s, 3H), 2.11 (d, J = 0.7 Hz, 3H), 3.95–
4.21 (m, 4H), 4.39 (d, J = 11.3 Hz, 1H), 5.40 (d, J = 11.3 Hz, 1H),
5.56 (d, J = 2.7 Hz, 1H), 7.41–7.45 (m, 2H), 7.51–7.55 (m, 1H),
7.69 (br s, 1H), 7.99–8.02 (m, 2H); 13C NMR (100.6 MHz, CDCl3) d
(ppm) 10.99 (q), 13.07 (q), 13.89 (q), 13.98 (q), 43.75 (d), 54.98
(d), 61.60 (t), 61.92 (t), 108.67 (d), 117.05 (s), 117.99 (s), 128.62
(s), 128.71 (d), 128.75 (d), 133.43 (d), 136.01 (s), 168.13 (s),
168.24 (s), 197.91 (s); IR (KBr) 3372, 2986, 2938, 1745, 1721,
1663, 1596, 1446, 1317, 1288, 1254, 1149, 1037 cmꢀ1; MS (EI)
m/z 371 (M+, 13), 266 (100%); HRMS M+ 371.1738 (calcd for
C21H25NO5 371.1733); Anal. Calcd for C21H25NO5: C, 67.91; H,
6.78; N, 3.77. Found: C, 67.91; H, 6.78; N, 3.75.
peak tR1 5.3 min, minor peak tR2 9.0 min, 38% ee; ½a D26
¼ ꢀ35 (c 1.00,
ꢃ
CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.37 (s, 9H), 1.92 (s, 3H),
2.12 (d, J = 0.7 Hz, 3H), 4.18 (d, J = 10.4 Hz, 1H), 4.30 (d, J = 10.4 Hz,
1H), 4.95 (d, J = 12.3 Hz, 1H), 4.99 (d, J = 12.3 Hz, 1H), 5.11 (d,
J = 12.4 Hz, 1H), 5.14 (d, J = 12.4 Hz, 1H), 5.59 (d, J = 2.7 Hz, 1H),
7.09–7.12 (m, 2H), 7.24–7.35 (m, 8H), 7.92 (br s, 1H); 13C NMR
(100.6 MHz, CDCl3) d (ppm) 10.81 (q), 13.07 (q), 27.88 (q), 43.21
(d), 54.79 (d), 67.38 (t), 67.43 (t), 81.96 (s), 108.28 (d), 117.72 (s),
118.15 (s), 127.39 (s), 128.14 (d), 128.16 (d), 128.30 (d), 128.36 (d),
128.52 (d), 128.58 (d), 135.11 (s), 135.25 (s), 167.63 (s), 167.68 (s),
170.75 (s); IR (neat) 3382, 2978, 1733, 1456, 1370, 1298,
1150 cmꢀ1; MS (EI) m/z 491 (M+, 26), 390 (22), 114 (67), 91 (100);
HRMS M+ 491.2311 (calcd for C29H33NO6 491.2308).
Compound 5 (Y = Ph) (37% yield); (Rf = 0.3 (CH2Cl2)): brown
crystals, HPLC (CHIRALPAK AS-H, hexane–iPrOH = 9:1) major peak
Compound 5b (Table 2, entry 1) (Rf = 0.2 (CH2Cl2)): brown oil;
tR1 4.6 min, minor peak tR2 6.6 min, 47% ee; ½a D19
¼ ꢀ10 (c 0.56,
ꢃ
HPLC (CHIRALPAK AD-H, hexane–iPrOH = 9:1) major peak tR1
CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.05 (t, J = 7.1 Hz, 3H),
1.11 (t, J = 7.1 Hz, 3H), 1.97 (s, 3H), 2.18 (d, J = 0.7 Hz, 3H), 3.96–
4.10 (m, 4H), 4.26 (d, J = 8.6 Hz, 1H), 4.86 (d, J = 8.6 Hz, 1H), 5.59
(d, J = 2.7 Hz, 1H), 7.15–7.21 (m, 3H), 7.24–7.28 (m, 2H), 8.54 (br
s, 1H); 13C NMR (100.6 MHz, CDCl3) d (ppm) 11.05 (q), 13.23 (q),
13.84 (q), 13.92 (q), 41.58 (d), 56.81 (d), 61.65 (t), 61.66 (t),
107.62 (d), 116.33 (s), 123.42 (s), 126.61 (s), 126.68 (d), 127.45
(d), 128.60 (d), 140.95 (s), 167.98 (s), 169.01 (s); IR (KBr) 3393,
2989, 2925, 1743, 1718, 1603, 1455, 1370, 1306, 1175,
11.6 min, minor peak tR2 15.0 min, 63% ee; ½a D21
¼ ꢀ96 (c 1.24,
ꢃ
CHCl3); 1H NMR (400 MHz, CDCl3) d (ppm) 1.11 (t, J = 7.1 Hz, 3H),
1.24 (t, J = 7.1 Hz, 3H), 1.25 (t, J = 7.1 Hz, 3H), 1.98 (s, 3H), 2.16
(d, J = 0.7 Hz, 3H), 3.97–4.27 (m, 6H), 4.11 (d, J = 10.6 Hz, 1H),
4.35 (d, J = 10.6 Hz, 1H), 5.59 (d, J = 2.7 Hz, 1H), 8.02 (br s, 1H);
13C NMR (100.6 MHz, CDCl3) d (ppm) 10.74 (q), 13.02 (q), 13.83
(q), 13.98 (q), 14.05 (q), 42.12 (d), 54.79 (d), 61.59 (t), 61.62 (t),
61.88 (t), 108.13 (d), 117.77 (s), 117.78 (s), 127.61 (s), 167.67 (s),