1240
N. Hoffmann, J.-P. Pete
PAPER
13C NMR (62 MHz, CDCl3): = 160.5, 157.7, 134.9, 119.0, 118.7,
112.7, 111.5, 110.3, 107.5, 68.1, 27.9, 25.7, 17.8.
MS (70eV): m/z (%) = 218 (45) [M+ + 1], 161 (42), 148 (55), 136
MS (70eV): m/z (%) = 283 (8) [M+ + 1], 251 (8), 205 (15), 184 (42),
183 (100), 182 (46), 155 (26), 154 (45), 151 (62), 139 (33), 124
(41), 123 (46).
(47), 135 (79), 118 (100).
Anal. Calcd for C15H22O5 (282): C, 63.83; H, 7.80. Found: C, 63.29;
H, 7.34.
Anal. Calcd for C13H15NO2 (217): C, 71.89; H, 6.91; N, 6.45.
Found: C, 71.68; H, 6.94; N, 6.26.
Compound 6 (isolated as a mixture with 5)
1H NMR (250 MHz, acetone-d6): = 3.79 (s, 3H), 3.74 (s, 3H), 1.09
(s, 3H), 0.97 (s, 3H).
Irradiation of Compounds 1a–d and 7a, b
Four quartz tubes each containing 16 mL of 1a–d or 7a, b (0.5
mmol) and in the case of acidic reaction media H2SO4 (0.1 mmol)
were irradiated (Rayonet, T = 30°C). After about 3 h, the reaction
was stopped and the solvent was evaporated. When the reaction was
carried out in acidic conditions, NaHCO3 was added prior to evap-
oration. The residue was subjected to flash chromatography (petro-
leum ether–EtOAc, 1:1, v/v) or (EtOAc). Yields of isolated
products are given in Tables 1 and 2.
13C NMR (62 MHz, acetone-d6): = 103.4, 61.79, 56.5, 44.8, 44.0,
27.6, 18.7.
Compound 8a
Mp 128°C.
IR (KBr): = 2986, 2926, 2232, 1649, 1614, 1395, 1215 cm–1.
1H NMR (250 MHz, acetone-d6): = 5.65 (d, 1H, J = 1.5 Hz), 4.28
(ddd, 1H, J = 1.5, 3.5, 8.5 Hz), 4.21, (ddd, 1H, J = 1.3, 8.5, 10.0 Hz),
3.52 (ddd, 1H, J = 4.5, 9.5, <1 Hz), 3.40 (ddt, 1H, J = 7.5, 15.0, 9.5
Hz), 2.63 (d, 1H, J = 18.5 Hz), 2.65 (ddd, 1H, J = 3.0, 8.0, 11.0 Hz),
2.57 (d, 1H, J = 18.5 Hz), 2.37 (dd, 1H, J = 10.0, 11.5 Hz), 2.14 (ddt,
1H, J = 9.5, 14.5, 1.5 Hz), 1.68 (dddd, 1H, J = 4.8, 8.0, 12.8, 15.5
Hz).
13C NMR (62 MHz, acetone-d6): = 191.9, 174.2, 124.2, 108.9,
68.8, 39.9, 38.6, 34.3, 30.2, 29.7.
MS (70eV): m/z (%) = 189 (5) [M+], 124 (9), 123 (100).
Compound 2 (R = H)
IR (film): = 2953, 2859, 1732, 1645, 1393, 1265, 1221, 1182 cm–1.
1H NMR (250 MHz, acetone-d6): = 5.63 (d, 1H, J = 1.5 Hz), 4.23
(ddd, 1H, J = 2.3, 4.2, 10.7 Hz), 4.15 (ddd, 1H, J = 1.5, 10.7, 12.5
Hz), 3.75 (s, 3H), 3.40 (ddd, 1H, J = 1.0, 3.9, 9.1 Hz), 3.10 (dp, 1H,
J = 7.6, 9.5 Hz), 2.57 (ddd, 1H, J = 3.9, 7.3, 11.4 Hz), 2.48 (d, 1H,
J = 18.7 Hz), 2.33 (d, 1H, J = 18.7 Hz), 2.15 (ddd, 1H, J = 1.0, 9.1,
10.5 Hz), 2.04 (ddt, 1H, J = 9.4, 14.0, 1.9 Hz), 1.62 (dddd, 1H,
J = 4.2, 8.8, 12.8, 14.0 Hz).
13C NMR (62 MHz, acetone-d6): = 194.0, 176.2, 175.9, 108.9,
69.0, 52.8, 46.0, 40.5, 38.7, 37.9, 30.7, 30.0.
MS (70eV): m/z (%) = 223 (90) [M+ + 1], 222 (100) [M+], 207 (35),
163 (92), 149 (27), 124 (94), 123 (66).
HRMS: calcd for C11H11NO2: 186.0808. Found: 186.0790.
Anal. Calcd for C11H21NO2 (189): C, 69.84; H, 5.82; N, 7.41.
Found: C, 69.29; H, 5.88; N, 7.27.
Compound 8b
Mp 153 °C.
HRMS: calcd for C12H14O4: 222.0892. Found: 222.0899.
IR (KBr): = 2967, 2934, 2234, 1649, 1615, 1360, 1177 cm–1.
Compound 3
IR (film): = 3420, 3946, 2861, 1728, 1644, 1605, 1217 cm–1.
1H NMR (250 MHz, acetone-d6): = 5.46 (d, 1H, J = 1.5 Hz), 4.31
(m, 1H, J = 10.5 Hz), 4.20 (m, 1H, J = 10.5 Hz), 3.48 (dd, 1H,
J = 1.5, 10.0 Hz), 3.13 (q, 1H, J = 10.0), 2.72 (d, 1H, J = 19.0 Hz),
2.56 (d, 1H, J = 19 Hz), 1.75 2.01 (m, 2H), 1.33 (s, 3H), 1.22 (s,
3H).
13C NMR (62 MHz, acetone-d6): = 192.6, 175.3, 123.7, 107.5,
68.2, 46.4, 41.0, 40.3, 36.9, 34.4, 29.4, 23.9, 20.0.
1H NMR (500 MHz, acetone-d6): = 5.58 (s, 1H), 3.76 (s, 3H), 3.75
(s, 3H), 3.40–3.50 (m, 1H), 2.98 (ddd, 1H, J = 5.7, 8.5, 9.5 Hz),
2.50–2.60 (m, 3H), 2.55 (d, 1H, J = 17 Hz), 2.28 (d, 1H, J = 17 Hz),
1.72 (t, 1H, J = 10 Hz), 1.65 (sext, 1H, J = 6.5 Hz), 1.20–1.35 (m,
2H).
13C NMR (126 MHz, acetone-d6): = 195.8, 176.1, 175.3, 104.0,
62.0, 59.8, 55.9, 52.8, 42.8, 41.9, 35.6, 35.1, 33.6.
MS (70eV): m/z (%) = 217 (15) [M+], 189 (15), 159 (12), 146 (11),
123 (100).
MS (70eV): m/z (%) = 255 (46) [M+ + 1], 195 (35), 181 (76), 182
(100), 154 (54), 151 (32), 123 (34).
HRMS: calcd for C13H15NO2: 217.1103. Found: 217.1100.
Anal. Calcd for C13H18O5 (254): C, 61.42; H, 7.09. Found: C, 61.02;
H, 7.20.
Compound 9
Mp 176°C (recrystallized from acetone–petroleum ether).
Compound 4 (isolated in a mixture with 3)
IR (KBr): = 3233, 2963, 2870, 1692, 1618, 1480, 1316, 1148,
1082, 855 cm–1.
1H NMR (500 MHz, acetone-d6): = 5.56 (d, 1h, J = 1.5 Hz), 3.75
(s, 3H), 2.32 (d, 1H, J = 18 Hz), 1.91 (t, 1H, J = 12.0 Hz), 1.58 (sext,
1H, J = 6.5 Hz).
1H NMR (500 MHz, acetone-d6): = 8.50 (br s, 1H), 6.50 (d, 1H,
J = 1.8 Hz), 6.37 (d, 1H, J = 1.8 Hz), 4.45 (ddd, 1H, J = 2.0, 11.5,
13.0 Hz), 4.21 (ddd, 1H, J = 2.0, 11.5, 13 Hz), 2.96 (dd, 1H, J = 5.0,
12 Hz), 2.00 (ddt, 1H, J = 13.0, 5.0, 2.0 Hz), 1.63 (dq, 1H, J = 4.0,
12.5 Hz), 1.17 (s, 3H), 0.81 (s, 3H).
13C NMR (126 MHz, acetone-d6): = 196.9, 176.0, 175.9, 103.7,
60.3, 56.4, 52.8, 48.6, 42.8, 36.7, 35.7, 34.3, 32.8.
Compound 5
13C NMR (126 MHz, acetone-d6): = 209.5, 160.0, 155.1, 136.2,
IR (film): = 3408, 2935, 1723, 1636, 1605, 1217 cm–1.
131.0, 107.8, 101.3, 68.4, 51.9, 43.7, 23.8, 22.5, 22.1.
MS (70eV): m/z (%) = 218 (95) [M+], 203 (54), 190 (100), 175 (45),
162 (56), 157 (23), 147 (62), 119 (25), 115 (46).
1H NMR (250 MHz, acetone-d6): = 5.45 (s, 1H), 3.74 (s, 3H), 3.70
(s, 3H), 3.60 (d, 1H, J = 10.3 Hz), 3.45–3.55 (m, 3H), 2.66 (d, 1H,
J = 18.0 Hz), 2.60 (dt, 1H, J = 10.3, 7.7 Hz), 2.39 (d, 1H, J = 18.0
Hz), 1.05 (s, 3H), 1.00 (s, 3H), 1.60 (m, 2H).
Anal. Calcd for C13H14O3 (218): C, 71.56; H, 6.42. Found: C, 71.47;
H, 6.20.
13C NMR (62 MHz, acetone-d6): = 196.8, 176.6, 175.1, 103.6,
61.2, 55.8, 52.0, 50.0, 43.6, 42.7, 38.3, 37.9, 30.9, 28.0, 19.4.
Compound 10a
IR (film): = 3391, 2942, 2236, 1640, 1597, 1387, 1215 cm–1.
Synthesis 2001, No. 8, 1236–1242 ISSN 0039-7881 © Thieme Stuttgart · New York