J.-m. Zhang et al. / Tetrahedron: Asymmetry 20 (2009) 355–361
359
4.3.3. Compound 9b
by GC using a Varian capillary column CP-Chirasil-DexCB (carrier:
N2, constant flow: 3.7 ml/min, oven temperature: 150 °C); tR
(major enantiomer) = 34.1 min, tR (minor enantiomer) = 36.2 min,
94% ee.
Yellow solid. 1H NMR (400 MHz, CDCl3): d = 9.51 (d, J = 2.0 Hz,
1H), 8.20 (d, J = 8.8 Hz, 2H), 7.44 (d, J = 8.4 Hz, 2H), 5.35 (dd, J = 4.8,
4.0 Hz, 1H), 3.90 (dd, J = 11.2, 4.8 Hz, 1H), 3.62 (ddd, J = 11.2, 3.6,
2.0 Hz, 1H); 13C NMR (100 MHz, CDCl3): d = 192.0, 147.8, 140.4,
127.9, 124.4, 62.4, 38.0, 35.7; IR (thin film)
m
/cmꢀ1: 2855 (w), 1713
4.3.9. Compound 9e
(s), 1604 (m), 1552 (s), 1519 (s), 1348 (s), 856 (m); HRMS (EI) calcd
for C10H8N2O5 (M+): 236.0433, found: 236.0435. The enantiomeric
excess was determined by HPLC with an AS-H column (n-hex-
ane/i-PrOH = 75/25, k = 220 nm, 1.0 ml/min); tR (major enantio-
mer) = 60.2 min, tR (minor enantiomer) = 66.8 min, 98% ee.
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.27 (d, J = 3.2 Hz,
1H), 7.16 (d, J = 8.4 Hz, 2H), 6.85 (d, J = 8.8 Hz, 2H), 5.25 (dd,
J = 4.8, 3.6 Hz, 1H), 3.78 (dd, J = 11.2, 4.8 Hz, 1H), 3.78 (s, 3H),
3.36 (dt, J = 11.2, 3.6 Hz, 1H); 13C NMR (100 MHz, CDCl3):
d = 193.1, 159.6, 129.9, 122.1, 114.4, 62.7, 55.26, 38.7, 35.8; IR (thin
film) m
/cmꢀ1: 2926 (m), 2852 (m), 1714 (s), 1613 (m), 1549 (s),
4.3.4. Compound 9b0
1517 (s), 1366 (m), 1251 (m), 1180 (m), 834 (m); HRMS (EI) calcd
for C11H11NO4 (M+): 221.0688, found: 221.0685. The enantiomeric
excess was determined by GC using a Varian capillary column
CP-Chirasil-DexCB (carrier: N2, constant flow: 3.7 ml/min, oven
temperature: 150 °C); tR (major enantiomer) = 56.2 min, tR (minor
enantiomer) = 60.3 min, 89% ee.
Yellow solid. 1H NMR (400 MHz, CDCl3): d = 9.70 (d, J = 4.4 Hz,
1H), 8.24 (d, J = 8.8 Hz, 2H), 7.37 (d, J = 8.8 Hz, 2H), 4.88 (dd,
J = 8.4, 4.8 Hz, 1H), 4.08 (dd, J = 7.8, 4.4 Hz, 1H), 2.79 (ddd, J = 8.0,
8.0, 4.4 Hz, 1H); 13C NMR (100 MHz, CDCl3): d = 192.2, 147.9,
137.4, 129.9, 124.0, 66.0, 38.9, 31.4. The enantiomeric excess was
determined by HPLC with an AS-H column (n-hexane/i-PrOH = 75/
25, k = 220 nm, 1.0 ml/min); tR (major enantiomer) = 33.1 min, tR
(minor enantiomer) = 38.8 min, 92% ee.
4.3.10. Compound 9e0
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.65 (d, J = 4.8 Hz,
1H), 7.08 (d, J = 8.4 Hz, 2H), 6.88 (d, J = 8.8 Hz, 2H), 4.74 (dd,
J = 8.0, 4.8 Hz, 1H), 3.94 (dd, J = 8.0, 4.8 Hz, 1H), 3.80 (s, 3H), 2.64
(ddd, J = 8.0, 8.0, 4.8 Hz, 1H); 13C NMR (100 MHz, CDCl3):
d = 193.3, 159.8, 128.0, 125.1, 114.6, 66.6, 55.35, 39.3, 32.2. The
enantiomeric excess was determined by GC using a Varian capil-
lary column CP-Chirasil-DexCB (carrier: N2, constant flow:
3.7 ml/min, oven temperature: 150 °C); tR (major enantio-
mer) = 82.0 min, tR (minor enantiomer) = 87.4 min, 96% ee.
4.3.5. Compound 9c
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.34 (d, J = 2.0 Hz,
1H), 7.30 (d, J = 6.8 Hz, 2H), 7.18 (d, J = 6.4 Hz, 2H), 5.26 (dd,
J = 3.8, 2.8 Hz, 1H), 3.78 (dd, J = 8.8, 3.6 Hz, 1H), 3.44 (dt, J = 8.8,
2.8 Hz, 1H); 13C NMR (100 MHz, CDCl3): d = 192.7, 134.4, 130.1,
129.0, 128.7, 62.4, 38.3, 35.6; IR (thin film)
m
/cmꢀ1: 2924 (m),
2854 (m), 1714 (s), 1551 (s), 1495 (m), 1364 (m), 1094 (m),
1015 (m), 827 (m); HRMS (EI) calcd for C10H8ClNO3 (M+):
225.0193, found: 225.0192. The enantiomeric excess was deter-
mined by GC using a Varian capillary column CP-Chirasil-DexCB
(carrier: N2, constant flow: 3.7 ml/min, oven temperature:
150 °C); tR (major enantiomer) = 49.6 min, tR (minor enantio-
mer) = 58.6 min, 91% ee.
4.3.11. Compound 9f
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.36 (d, J = 2.8 Hz,
1H), 7.29–7.12 (m, 4H), 5.28 (dd, J = 4.8, 3.6 Hz, 1H), 3.80 (dd,
J = 11.2, 4.8 Hz, 1H), 3.46 (dt, J = 11.2, 3.2 Hz, 1H); 13C NMR
(100 MHz, CDCl3): d = 192.5, 135.18, 132.2, 130.2, 129.1, 128.85,
127.0, 62.2, 38.2, 35.6; IR (thin film) m
/cmꢀ1: 2925 (w), 2852 (w),
4.3.6. Compound 9c0
1714 (m), 1636 (s), 1549 (m), 1364 (m), 1082 (w), 784 (w); HRMS
(EI) calcd for C10H8ClNO3 (M+): 225.0193, found: 225.0195. The
enantiomeric excess was determined by GC using a Varian capil-
lary column CP-Chirasil-DexCB (carrier: N2, constant flow:
3.7 ml/min, oven temperature: 140 °C); tR (major enantio-
mer) = 74.9 min, tR (minor enantiomer) = 77.0 min, 96% ee.
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.64 (d, J = 4.0 Hz,
1H), 7.34 (d, J = 6.8 Hz, 2H), 7.12 (d, J = 6.8 Hz, 2H), 4.77 (dd,
J = 6.6, 4.0 Hz, 1H), 3.95 (dd, J = 6.0, 4.0 Hz, 1H), 2.66 (ddd, J = 6.4,
6.4, 3.6 Hz, 1H); 13C NMR (100 MHz, CDCl3): d = 192.8, 134.5,
131.8, 129.3, 128.2, 66.3, 38.9, 31.7. The enantiomeric excess was
determined by GC using a Varian capillary column CP-Chirasil-
DexCB (carrier: N2, constant flow: 3.7 ml/min, oven temperature:
150 °C); tR (major enantiomer) = 77.5 min, tR (minor enantio-
mer) = 84.0 min, 95% ee.
4.3.12. Compound 9f0
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.67 (d, J = 4.4 Hz,
1H), 7.33–7.06 (m, 4H), 4.79 (dd, J = 8.4, 4.8 Hz, 1H), 3.96 (dd,
J = 7.8, 4.8 Hz, 1H), 2.69 (ddd, J = 8.0, 8.0, 4.8 Hz, 1H); 13C NMR
(100 MHz, CDCl3): d = 192.6, 135.22, 134.9, 130.5, 128.89, 127.1,
125.1, 66.1, 38.8, 31.7. The enantiomeric excess was determined
by GC using a Varian capillary column CP-Chirasil-DexCB (carrier:
N2, constant flow: 3.7 ml/min, oven temperature: 140 °C); tR
(major enantiomer) = 108.8 min, tR (minor enantiomer) =
118.5 min, 96% ee.
4.3.7. Compound 9d
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.26 (d, J = 2.8 Hz,
1H), 7.17–7.09 (m, 4H), 5.27 (dd, J = 3.8, 3.2 Hz, 1H), 3.80 (dd,
J = 8.8, 4.0 Hz, 1H), 3.37 (dt, J = 9.2, 2.8 Hz, 1H), 2.32 (s, 3H); 13C
NMR (100 MHz, CDCl3): d = 193.1, 138.5, 129.6, 128.6, 126.7,
62.5, 38.6, 36.0, 21.1; IR (thin film) m
/cmꢀ1: 2925 (w), 1715 (s),
1549 (s), 1456 (w), 1363 (s), 1122 (m), 807 (w); HRMS (EI) calcd
for C11H11NO3 (M+): 205.0739, found: 205.0737. The enantiomeric
excess was determined by GC using a Varian capillary column
CP-Chirasil-DexCB (carrier: N2, constant flow: 3.7 ml/min, oven
temperature: 150 °C); tR (major enantiomer) = 24.7 min, tR (minor
enantiomer) = 25.9 min, 94% ee.
4.3.13. Compound 9g
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.43 (d, J = 2.0 Hz,
1H), 7.38–7.25 (m, 4H), 5.22 (dd, J = 4.0, 3.2 Hz, 1H), 3.73 (dd,
J = 8.6, 3.6 Hz, 1H), 3.56 (ddd, J = 8.8, 2.8, 2.0 Hz, 1H); 13C NMR
(100 MHz, CDCl3): d = 192.1, 134.7, 130.5, 129.9, 127.9, 127.3,
127.0, 62.8, 37.6, 34.7; IR (thin film) m
/cmꢀ1: 2925 (m), 2853 (m),
4.3.8. Compound 9d0
1715 (s), 1550 (s), 1479 (m), 1441 (m), 1364 (s), 1131 (w), 755
(m); HRMS (EI) calcd for C10H8ClNO3 (M+): 225.0193, found:
225.0190. The enantiomeric excess was determined by GC using
a Varian capillary column CP-Chirasil-DexCB (carrier: N2, constant
flow: 3.7 ml/min, oven temperature: 150 °C); tR (major enantio-
mer) = 28.8 min, tR (minor enantiomer) = 27.4 min, 88% ee.
Yellow oil. 1H NMR (400 MHz, CDCl3): d = 9.66 (d, J = 4.0 Hz,
1H), 7.21–7.00 (m, 4H), 4.76 (dd, J = 6.4, 3.6 Hz, 1H), 3.95 (dd,
J = 6.2, 3.6 Hz, 1H), 2.66 (ddd, J = 6.4, 6.4, 4.0 Hz, 1H), 2.34 (s, 3H);
13C NMR (100 MHz, CDCl3): d = 193.3, 138.6, 129.8, 128.5, 127.2,
62.7, 39.3, 32.4, 29.7. The enantiomeric excess was determined