E.M. Coyanis et al. / Journal of Organometallic Chemistry 691 (2006) 5222–5239
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OCH3), 2.18–1.60 (multiple s, 6H, 2 · CH3), 1.55–1.41
(multiple s, 4H, OH and CH3), 1.28–1.17 (m, 6H,
2 · CH3); 13C NMR (50 MHz, CDCl3, assignments with
the same superscript may be interchanged): d = 152.7,
152.4, 152.3, 152.1 (C), 147.4, 147.0, 146.8, 146.6 (C),
143.9, 143.8, 143.6 (C), 142.0, 142.0, 137.0, 136.0 (C),
133.5, 132.9, 132.8 (C), 132.2, 132.1, 131.9, 131.8 (C),
125.2, 124.3, 123.3, 122.8, 121.7, 121.6, 121.4 (2 · CH),
110.5, 110.4, 110.4, 110.3, 110.2, 109.8 (2 · CH) 75.3,
74.9, 74.9 [OCH(CH3)2],a 73.5, 73.3 (CHOH),a 55.4 br
(OCH3), 25.1, 24.3 (CH3), 22.6, 22.5, 22.5 [OCH(CH3)2],
19.9, 19.8, 19.4, 19.1, 17.9, 17.6, 15.7, 15.6, 13.4
(2 · CH3); IR (thin film, cmꢀ1): 3398 br, 1652, 1596,
1573, 1480, 1429, 1379, 1347; HRMS (EI): Calculated for
C18H26O3: 290.1882, found: 290.1882; m/z: 291 (M++1,
15), 290 (76), 273 (44), 261 (25), 248 (36), 247 (24), 219
(77), 207 (30), 206 (41), 205 (52), 191 (41), 187 (100), 177
(20), 171 (28), 157 (19), 145 (16), 91 (15), 43 (29), 41 (25).
Synthesis of indenols – general description: Grubbs cata-
lyst 19 was added to a degassed solution (N2) of the diene
29 in CH2Cl2 or toluene. The solution was then stirred
under N2 at room temperature (or else at the specified tem-
perature) for an appropriate time until all starting material
had been consumed (confirmed by tlc). After evaporation
of the solvent and column chromatographic purification
of the residue (20% EtOAc–hexane) the indenols were
obtained as listed below.
4.99 (br s, 1H, H-1), 4.63 [sept, 1H, J = 6.2 Hz, CH(CH3)2],
3.82 (s, 3H, OCH3), 2.22 (s, 3H, CH3), 1.86 (br s, 1H, OH),
1.28 [d, 3H, J = 6.2 Hz, CH(CH3)CH3], 1.22 [d, 3H,
J = 6.2 Hz, CH(CH3)CH3]; 13C NMR (50 MHz, CDCl3,
assignments with superscripts may be interchanged):
d = 153.6 (C), 141.6 (C), 141.2 (C), 140.1 (C), 136.5 (C),
133.4 (CH), 116.2 (CH), 109.6 (CH), 75.4 (C-1),a 74.2
[CH(CH3)2],a 56.0 (OCH3), 22.5, 22.3 [CH(CH3)2], 16.6
(CH3); IR (thin film, cmꢀ1): 3385 br, 1639, 1596, 1573,
1481, 1429; HRMS (EI): Calculated mass for C14H18O3:
234.1256, found: 234.1259; m/z: 234 (M+, 28%), 194 (52),
193 (33), 192 (35), 191 (46), 190 (49), 179 (91), 177 (35),
175 (23), 167 (20), 163 (22), 162 (20), 151 (72), 149 (53),
147 (25), 135 (23), 131 (20), 103 (21), 91 (35), 83 (23), 81
(23), 79 (22), 77 (38), 73 (45), 71 (30), 69 (57), 57 (100),
56 (21), 55 (54), 51 (20), 43 (86), 41 (99).
4-Isopropoxy-5-methoxy-3-phenyl-1H-inden-1-ol
32c
(R1 = Ph, R2 = H). Diene 29c (R1 = Ph, R2 = H)
(0.071 g, 0.21 mmol) was treated with catalyst 19 (0.009 g,
5%) in CH2Cl2 (15 cm3) for 2 h at temp, as described
above, to afford 32c (0.041 g, 67%) as a pale cream-col-
oured solid (mp = 56–59 ꢁC, recrystallized from EtOAc–
1
hexane). H NMR (200 MHz, CDCl3): d = 7.53–7.48 (m,
2H, 2 · ArH), 7.40–7.31 (m, 3H, 3 · ArH), 7.23 (d, 1H,
J = 7.6 Hz, H-7), 6.77 (d, 1H, J = 7.6 Hz, H-6), 6.23 (d,
1H, J = 2.0 Hz, H-2), 5.17 (br s, 1H, H-1), 3.92 [sept,
1H, J = 6.1 Hz, CH(CH3)2], 3.83 (s, 3H, OCH3), 2.02 (br
s, 1H, OH, D2O exchangeable), 0.73 [d, 3H, J = 6.1 Hz,
CH(CH3)CH3], 0.67 [d, 3H, J = 6.1 Hz, CH(CH3)CH3];
13C NMR (50 MHz, CDCl3, C-1 carbon under chloroform
signal): d = 154.5 (C), 146.0 (C), 141.3 (C), 139.8 (C), 136.2
(CH), 136.1 (C), 135.0 (C), 128.8 (2 · CH), 127.5 (CH),
127.3 (2 · CH), 116.9 (CH), 109.5 (CH), 75.6 [CH(CH3)2],
55.9 (OCH3), 21.4, 21.3 [CH(CH3)2]; IR (thin film, cmꢀ1):
3375 br, 1690, 1593, 1476, 1442; HRMS (EI): Calculated
mass for C19H20O3: 296.1412, found: 296.1413; m/z: 296
(M+, 45), 294 (20), 256 (24), 255 (30), 254 (39), 253 (45),
252 (100), 241 (26), 239 (20), 181 (25), 165 (23), 152 (30),
117 (43), 105 (25), 77 (26), 43 (52), 41 (25).
4-Isopropoxy-5-methoxy-1H-inden-1-ol
32a
(R1,
R2 = H). Diene 29a (R1, R2 = H) (0.26 g, 1.00 mmol) was
treated with catalyst 19 (0.043 g, 5%) in CH2Cl2 (25 cm3)
for 3 h at rt, as described above, to afford 32a as a pale yel-
low oil (0.191 g, 87%). On a smaller scale (29a, 0.16 g) inde-
1
nol 32a (0.088 g, 64%) was isolated in a lower yield. H
NMR (200 MHz, CDCl3, assignments with superscripts
may be interchanged): d = 7.12 (d, 1H, J = 7.9 Hz, H-7),
6.73 (d, 1H, J = 5.6 Hz, H-3),a 6.66 (d, 1H, J = 7.9 Hz,
H-6),a 6.27 (dd, 1H, J = 5.6 and 2.0 Hz, H-2), 5.04 (br s,
1H, H-1), 4.33 [br sept, 1H, J = 6.2 Hz, CH(CH3)2], 3.80
(s, 3H, OCH3), 2.08 (br s, 1H, OH), 1.28 [d, 3H,
J = 6.4 Hz, CH(CH3)CH3], 1.25 (d, 3H, J = 6.5 Hz,
CH(CH3)CH3); 13C NMR (50 MHz, CDCl3, assignments
with superscripts may be interchanged): d = 153.3 (C),
140.1 (C), 138.4 (C), 137.8 (CH), 136.7 (C), 129.2 (CH),
118.9 (CH), 109.4 (CH), 77.1 (C-1),b 75.6 [CH(CH3)2],b
55.9 (OCH3), 22.5, 22.4 [CH(CH3)2]; IR (thin film, cmꢀ1):
3400 br, 1674, 1617, 1596, 1556, 1482, 1440; HRMS (EI):
Calculated for C13H16O3: 220.1099, found: 220.1099; m/z:
220 (M+, 69), 179 (18), 178 (100), 177 (28), 176 (16), 163
(41), 161 (12), 149 (16), 147 (18), 146 (18), 135 (10), 118
(10), 77 (10), 57 (14), 55 (12), 43 (28), 41 (19).
4-Isopropoxy-5-methoxy-2-methyl-1H-inden-1-ol
32d
(R1 = H, R2 = Me). Diene 29d (R1 = H, R2 = Me)
(0.12 g, 0.44 mmol) was treated with catalyst 19
(0.018 g · 2, 10%) in toluene (15 cm3) for 24 h at 60 ꢁC,
as described above, to afford 32d as a pale yellow oil
1
(0.050 g, 49%) as well as indenone 35d (0.024 g, 24%). H
NMR (200 MHz, CDCl3): d = 7.07 (d, 1H, J = 7.8 Hz,
H-7), 6.57 (d, 1H, J = 7.8 Hz, H-6), 6.32 (s, 1H, H-3),
4.76 (s, 1H, H-1), 4.23 [sept, 1H, J = 6.1 Hz, CH(CH3)2],
3.80 (s, 3H, OCH3), 2.22 (br s, 1H, OH), 2.02 (s, 3H,
CH3), 1.28 [d, 3H, J = 6.4 Hz, CH(CH3)CH3], 1.24 (d,
3H, J = 6.4 Hz, CH(CH3)CH3); 13C NMR (50 MHz,
CDCl3, assignments with superscripts may be inter-
changed): d = 153.5 (C), 148.3 (C), 139.2 (C), 138.3 (C),
137.2 (C), 123.5 (CH), 118.6 (CH), 106.1 (CH), 78.6 (C-
1),a 75.4 [CH(CH3)2],a 55.8 (OCH3), 22.5, 22.4 [CH(CH3)2],
13.9 (CH3); IR (thin film, cmꢀ1): 3385 br, 1625, 1484, 1439,
1382, 1372; HRMS (EI): Calculated mass for C14H18O3:
4-Isopropoxy-5-methoxy-3-methyl-1H-inden-1-ol
32b
(R1 = Me, R2 = H). Diene 29b (R1 = Me, R2 = H)
(0.060 g, 0.22 mmol) was treated with catalyst 19 (0.011 g,
5%) in CH2Cl2 (15 cm3) for 2 h at rt, as described above,
to afford 32b as a pale yellow oil (0.035 g, 64%). 1H
NMR (200 MHz, CDCl3): d = 7.10 (d, 1H, J = 6.9 Hz,
H-7), 6.68 (d, 1H, J = 7.9 Hz, H-6), 5.93 (br s, 1H, H-2),