M. Searcey et al. / Tetrahedron Letters 44 (2003) 6745–6747
6747
Development, Dept. of Research and Technology,
Greece for a sabbatical leave (P.G.T.). We thank Dr.
(s, 4H), 2.60 (s, 6H), 2.49 (s, 1H); 13C NMR (DMSO-d6,
62.9 MHz) l 154.0, 129.0, 128.0, 126.5, 123.8, 115.0, 48.8;
20.0 FABMS m/z 258 (30%, M++H), 185 (15), 136 (40),
121 (100), HRMS calcd for C16H20NO2: 258.1478. Found
M+H+ 258.1494. Anal. calcd for C16H20NO2·1H2O; C,
69.91; H, 7.63; N, 5.09. Found: C, 70.08; H, 7.23; N,
5.68. 7c: 1H NMR (DMSO-d6, 250 MHz) l 6.72 (m, 2H),
6.65 (m, 4H), 3.70 (s, 4H), 3.68 (s, 6H); 13C NMR
(DMSO-d6, 62.9 MHz) l 152.0, 150.0, 125.0, 116.0,
115.0, 113.0, 55.0, 47.0; FABMS m/z 290 (100%, M++1),
199 (55), 176 (22). Anal. calcd for C16H19NO4·0.2H2O; C,
65.62; H, 6.63; N, 4.78. Found: C, 65.31; H, 6.51; N,
4.75. 7d: 1H NMR (DMSO-d6, 250 MHz) l 7.40 (m, 2H),
6.60 (m, 4H), 4.00 (s, 2H), 3.90 (s, 2H), 3.60 (br s, 6H);
FABMS m/z 289 (15%, M+), 288 (75), 152 (100), 137
(100), 107 (25), HRMS calcd for C16H18NO4 288.1231.
Found M−H+ 288.1236. 7e: 1H NMR (DMSO-d6, 250
MHz) l 9.5 (s, 2H), 7.64 (d, J=8.52 Hz, 2H), 7.76 (d,
J=7.97 Hz, 2H), 7.60 (d, J=8.80 Hz, 2H), 7.44 (dd,
J=7.42, 7.42 Hz, 2H), 7.25 (dd, J=7.28, 7.28 Hz, 2H),
7.17 (d, J=8.52 Hz, 2H), 3.32 (s, 1H), 2.40 (s, 4H); 13C
NMR (DMSO-d6, 62.9 MHz) l 152.0, 134.0, 128.1,
127.9, 126.5, 126.0, 122.5, 122.0, 118.0, 114.5, 10.0;
FABMS m/z 329 (55%, M+), 289 (25), 173 (100).
7. Caddick, S.; Haynes, A. K.; de, K.; Judd, D. B.;
Williams, M. R. V. Tetrahedron Lett. 2000, 41, 3513.
8. (a) Molina, P.; Alajarin, M.; Vilaplana, M. J. Synthesis
1982, 12, 1016; (b) Arrieta, A.; Aizpurua, J. M.; Palomo,
C. Tetrahedron Lett. 1994, 25, 3365.
1
M. Zloh for H and 13C NMR and Mr. M. Cocksedge
for mass spectra.
References
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EtOAc (50 mL) was then added, the mixture filtered
through Celite and the Celite was washed with EtOAc (50
mL). The combined organics were concentrated. Chro-
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the product as a yellow solid (1 g, 65%).
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6. Compound 7a: 1H NMR (DMSO-d6, 250 MHz) l 7.07
(m, 4H), 6.74 (m, 4H), 3.75 (s, 4H), 2.49 (s, 1H); 13C
NMR (DMSO-d6, 62.9 MHz) l 156.5, 129.0, 127.8,
124.1, 118.5, 115.0, 48.8; FABMS m/z 230 (50%, M++H),
197 (25), 135 (55), 115 (50), 107 (100), HRMS calcd for
C14H16NO2: 230.1176. Found M+H+ 230.1181. Anal.
calcd for C14H16NO2·0.2H2O; C, 72.22; H, 6.62; N, 6.01.
Found: C, 72.48; H, 6.45; N, 6.07%. 7b: 1H NMR
(DMSO-d6, 250 MHz) l 7.30 (m, 4H), 7.00 (m, 2H), 4.10