B. G. Roy et al. / Tetrahedron Letters 47 (2006) 8821–8825
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16. Iacono, S.; Rasmussen, J. R. Org. Synth., Coll. 1990, 7, 139.
17. Giese, B.; Gonzalez-Gomez, J. A.; Witzel, T. Angew.
Chem., Int. Ed. Engl. 1984, 23, 69.
18. The crude mixture of 17 and 18 showed appropriate
aromatic proton signals in the 1H NMR spectrum and
exhibited the pseudomolecular ion peak in the ESIMS
spectrum at m/z 332 (M+Na)+.
19. Preparation of 8: To a stirred solution of 7a (4.0 g,
10.1 mmol) in benzene (250 ml) was added allyl tri-n-
butyltin (8.3 g, 25.0 mmol) and the mixture was poured
under an Ar atmosphere into a Hanovia flask, equipped
with a magnetic stirrer, a cold water circulator and a
460 W filament inside a Pyrex glass. The reaction temper-
ature was set at 10 ꢁC; the UV light was switched on and
passed through the Pyrex glass to transmit only the desired
wavelength (360 nm) of light. After 40 h, the solvent was
evaporated to give a crude oil, which was purified by
column chromatography on silica gel (60–120 mesh) using
petroleum ether:ethyl acetate (85:15) as the eluent to
(2 · CH), 136.9 (C); FABMS, m/z: 250 (M+H)+. Anal.
Calcd for C14H19NO3: C, 67.45; H, 7.68; N, 5.62. Found:
25
C, 67.18; H, 7.50, N, 5.34. Compound 15: Foam. ½aꢁD
ꢀ36.8 (c 0.39, MeOH); 1H NMR (D2O, 300 MHz): d
1.79–1.95 (m, 2H), 2.50 (m, 1H), 2.72 (m, 1H), 3.19 (br d,
2H, J = 6.0 Hz), 3.60 (dd-like, 1H, J = 7.5, 10.0 Hz), 3.77
(dd, 1H, J = 4.8, 9.8 Hz), 4.94–5.09 (m, 2H ), 8.58 (s,
1H), 8.62 (s, 1H); 13C NMR (CDCl3, 75 MHz): d 28.1
(CH2), 39.5 (CH), 41.2 (CH), 61.5 (CH2), 61.7 (CH2),
63.9 (CH), 74.9 (CH), 131.3 (C), 146.8 (CH), 150.6 (C)
152.1(CH), 152.8 (C); ESIMS, m/z: 321 [(M+Na)+ for
Cl35], 323 [(M+Na)+ for Cl37]. Anal. Calcd for
C12H15ClN4O3: C, 48.25; H, 5.06; N, 18.76. Found: C,
25
48.28; H, 5.00, N, 18.47. Compound 19: ½aꢁD +48.9 (c
0.68, CHCl3); IR, 1H and 13C NMR spectra of 19 are
practically identical with those of 13. Anal. Calcd for
C14H19NO3: C, 67.45; H, 7.68; N, 5.62. Found: C, 67.22;
25
H, 7.43, N, 5.42. Compound 20: Gum. ½aꢁD +43.4 (c
0.84, CHCl3); 1H NMR (CDCl3+D2O, 300 MHz): d
1.74–1.94 (m, 3H), 3.15 (m, 1H), 3.62 (dd, 1H, J = 5.4,
9.4 Hz), 3.69 (dd, 1H, J = 3.0, 8.7 Hz), 3.75 (dd, 1H,
J = 5.7, 11.4 Hz), 3.89–3.95 (m, 3H), 4.11 (dd, 1H,
J = 6.7, 8.7 Hz), 4.24 (d, 1H, J = 12.6 Hz), 7.26–7.40
(m, 5H); 13C NMR (CDCl3, 75 MHz): d 30.3 (CH2),
47.9 (CH), 48.3 (CH), 60.2 (CH2), 61.5 (CH2), 71.6
(CH2), 72.2 (CH), 72.5 (CH), 127.6 (CH), 128.4 (2 · CH),
128.8 (2·CH), 136.6 (C); EIMS, m/z: 249 (M)+. Anal.
Calcd for C14H19NO3: C, 67.45; H, 7.68; N, 5.62. Found:
25
afford 8 (2.30 g, 80%) as a colourless oily liquid. ½aꢁD
ꢀ21.4 (c 0.56, CHCl3); 1H NMR (CDCl3, 300 MHz): d
1.30 (s, 3H), 1.35 (s, 3H), 1.42 (s, 3H), 1.52 (s, 3H), 1.87
(m, 1H), 2.43 (m, 2H), 3.93 (dd, 1H, J = 4.5, 7.8 Hz),
4.02–4.16 (m, 3H), 4.51 (d, 1H, J = 3.6 Hz), 5.06–5.13 (m,
2H), 5.74 (d, 1H, J = 3.6 Hz), 5.78 (partially merged m,
1H); 13C NMR (CDCl3, 75 MHz): d 25.7 (CH3), 26.5
(CH3), 27.1 (CH3), 27.2 (CH3), 30.0 (CH2), 45.7 (CH),
68.9 (CH2), 72.7 (CH), 81.0 (CH), 83.9 (CH), 105.2 (CH),
109.7 (C), 111.5 (C), 117.6 (CH2), 136.1 (CH); ESIMS,
m/z: 307 (M+Na)+. Anal. Calcd for C15H24O5: C, 63.36;
H, 8.51. Found: C, 63.10; H, 8.35.
25
C, 67.39; H, 7.47, N, 5.34. Compound 21: Foam. ½aꢁD
+37.1 (c 0.24, MeOH); 1H and 13C NMR spectra
virtually match those of 15. Anal. Calcd for C12H15-
ClN4O3: C, 48.25; H, 5.06; N, 18.76. Found: C, 48.10; H,
25
20. Compound 11: colourless solid. ½aꢁD ꢀ26.6 (c 0.81,
25
CHCl3); 1H NMR (CDCl3, 600 MHz): d 1.27 (s, 3H),
1.46 (s, 3H), 1.46–1.52 (partially merged signal, 1H), 1.80
(dd, 1H, J = 8.4, 13.2 Hz), 2.84–2.88 (m, 1H), 3.23–3.28
(m, 1H), 3.49 (dd, 1H, J = 4.8, 8.4 Hz), 3.59 (d, 1H,
J = 7.8 Hz), 3.85 (d, 1H, J = 13.2 Hz), 3.97 (d, 1H, J =
13.2 Hz), 4.16 (t, 1H, J = 8.4 Hz), 4.50 (d, 2H,
J = 3.6 Hz), 5.79 (d, 1H, J = 3.6 Hz), 7.24–7.36 (m,
5H); 13C NMR (CDCl3, 75 MHz): d 26.2 (CH3), 26.9
(CH3), 32.2 (CH2), 47.5 (CH), 48.9 (CH), 60.8 (CH2),
72.2 (CH2), 74.9 (CH), 84.0 (CH), 88.8 (CH), 105.6 (CH),
111.3 (C), 127.5 (CH), 128.4 (2 · CH), 129.0 (2 · CH),
136.6 (C); FABMS, m/z: 318 (M+H)+. Anal. Calcd for
C18H23NO4: C, 68.12; H, 7.30; N, 4.41. Found: C, 68.18;
4.86; N, 18.61. Compound 22: Foam.½aꢁD +25.4 (c 0.31,
MeOH); 1H NMR (D2O, 300 MHz): d 1.37–1.48 (m,
1H), 2.07–2.17 (m, 1H), 2.31 (m, 1H), 2.79 (m, 1H), 3.31
(d, 2H, J = 6.0 Hz), 3.63 (dd, 1H, J = 6.0, 10.8 Hz), 3.78
(dd, 1H, J = 8.0, 10.8 Hz), 4.46 (t, 1H, J = 3.6 Hz), 5.23
(dd, 1H, J = 4.0, 10.0 Hz), 8.67 (s, 1H), 8.87 (s, 1H); 13C
NMR (DMSO-d6, 150 MHz): d 28.6 (CH2), 40.7 (CH),
44.9 (CH), 58.6 (CH), 60.3 (CH2), 61.9 (CH2), 71.7 (CH),
129.9 (C), 147.8 (CH), 148.7 (C), 151.3 (CH) 152.8 (C);
ESIMS, m/z: 321 [(M+Na)+ for Cl35], 323 [(M+Na)+ for
Cl37]. Anal. Calcd for C12H15ClN4O3: C, 48.25; H, 5.06;
N, 18.76. Found: C, 47.98; H, 4.88; N, 18.53.
21. Crystallographic data, 11: MF = C18H23NO4, M =
317.37, orthorhombic, space group P212121, a = 6.9512
25
H, 7.18, N, 4.15. Compound 13 : Gum. ½aꢁD ꢀ48.5 (c
1
˚
0.72, CHCl3); H NMR (CDCl3+D2O, 300 MHz): d 1.52
(5), b = 13.4852 (10), c = 17.3143 (13) A, U = 1623.0
3
(2) A , Z = 4, calcd = 12.99 g cmꢀ3. 4741 Independent
˚
(dd, 1H, J = 6.8, 12.6 Hz), 1.96–2.07 (m, 1H), 2.33–2.37
(m, 1H), 3.23 (m, 1H), 3.32 (d, 1H, J = 8.0 Hz), 3.49 (dd,
1H, J = 4.8, 8.5 Hz), 3.75 (dd, 1H, J = 6.8, 11.0 Hz), 3.86
(d, 1H, J = 13.0 Hz), 3.88 (partially merged dd, 1H,
J = 4.0, 10.8 Hz), 4.03 (d, 1H, J = 13.0 Hz), 4.04 (d, 1H,
J = 4.0 Hz), 4.17 (t, 1H, J = 8.0 Hz), 7.29–7.38 (m, 5H);
13C NMR (CDCl3, 150 MHz): d 30.5 (CH2), 43.7 (CH),
45.5 (CH), 61.3 (CH2), 61.7 (CH2), 72.7 (CH2), 77.8
(CH), 78.6 (CH), 127.4 (CH), 128.3 (2 · CH), 129.0
reflections were measured using MoKa radiation at
150 K on an Oxford Instruments X-Calibur CCD diffrac-
tometer and refined to R1 0.0522. wR 2 0.1022. Torsion
angle between H-13 and H-14 is ꢀ99.1 and between H-4
and H-14 is 9.4. Crystal data have been deposited at the
Cambridge Crystallographic Data Centre with reference
number CCDC 619424. Data can be obtained via