Synthesis of 3-Aryloxy-2-iodoemodines
FULL PAPER
(270 mg, 1 mmol) in methanol (25 mL) was added to a solution of
CH3), 6.74 (s, 1 H, 4-H), 6.95 (s, 1 H, 4Ј-H), 7.08 (s, 1 H, 7-H),
(diacetoxyiodo)arene 2aϪf (1 mmol) and stirred at 0 °C for 4 h. 7.52 (s, 1 H, 5-H), 11.93 (s, 1 H, 8-OH), 13.30 (s, 1 H, 8-OH), 13.30
Acetone (250 mL) was added, and the solution was stirred at 30
(s, 1 H, 1-OH) ppm. 13C NMR (CDCl3): δ ϭ 12.58, 19.76, 22.26
°C for 24 h. The reaction’s progress was monitored by TLC. After
(CH3), 84.01 (C-2), 104.98 (C-4), 110.72 (C-9a), 113.23 (C-8a),
completion of the reaction, the organic solvent was removed by 121.38 (C-5), 124.78 (C-7), 126.15 (C-2Ј, C-6Ј), 129.47 (C-4Ј),
rotary evaporation at reduced pressure. The residue was suspended
in a solvent mixture of petroleum ether/ethyl acetate/acetic acid
(20/20/1) and filtered. The filtrate was evaporated under reduced
pressure and purified by column chromatography and/or recrystal-
lization.
133.01, 135.15 (C-4a, C-10a), 149.03 (C-6), 150.24 (C-1Ј), 162.65,
163.91, 164.10 (C-OH), 181.66 (C-10), 190.61 (C-9) ppm.
1,8-Dihydroxy-2-iodo-6-methyl-3-(2,3,4,5,6-pentamethylphenoxy)-
anthraquinone (4f): Yield 120 mg (22%), m.p. 300Ϫ305 °C, yellow
plates. UV (CHCl3): λmax. ϭ 440 nm. IR (KBr): ν˜ ϭ 3429, 2923,
1675, 1625 cmϪ1. MS calculated for C26H23IO5 [M]: 542.37,
MALDI-MS [M]Ϫ found: 542.3. 1H NMR (CDCl3): δ ϭ 2.02 (s, 6
H, 3Ј-CH3, 5Ј-CH3), 2.24 (s, 6 H, 2Ј-CH3, 6Ј-CH3), 2.27 (s, 3 H,
4Ј-CH3), 6.74 (s, 1 H, 4-H), 7.09 (s, 1 H, 7-H), 7.52 (s, 1 H, 5-H),
11.95 (s, 1 H, 8-OH), 13.32 (s, 1 H, 1-OH) ppm. 13C NMR
(CDCl3): δ ϭ 13.42, 18.53, 28.23, 22.30 (CH3), 84.13, 105.15,
110.66 (C-9a), 113.23 (C-8a), 121.36 (C-5), 124.78 (C-7), 125.66 (C-
2Ј, C-6Ј), 134.31 (C-4Ј), 134.94 (C-3Ј, C-5Ј), 133.01, 135.11 (C-4a,
C-10a), 148.15 (C-6), 148.15 (C-6), 148.97 (C-1Ј), 162.61, 163.88,
164.38 (C-0 H), 181.74 (C-10), 190.57 (C-9) ppm.
1,8-Dihydroxy-2-iodo-6-methyl-3-phenoxyanthraquinone (4a): Yield
100 mg (21%), m.p. 263Ϫ264 °C, yellow plates. UV (acetone):
λmax. ϭ 433 nm. IR (KBr): ν˜ ϭ 3423, 1672, 1625, 1560 cmϪ1. MS
calculated for C21H13IO5 [M]: 472.24, MALDI-MS [M]Ϫ found:
1
472.2. H NMR (CDCl3): δ ϭ 2.45 (s, 3 H, CH3), 6.84 (s, 1 H, 4-
H), 7.47 (s, 1 H, 5-H), 7.21Ϫ7.23 (m, 3 H, 2Ј-H, 6Ј-H, 7-H), 7.37
(d, J ϭ 7.6 Hz, 1 H, 4Ј-H), 11.93 (s, 1 H, 8-OH), 13.32 (s, 1 H, 1-
OH) ppm. 13C NMR (CDCl3): δ ϭ 22.27 (CH3), 84.21 (C-2),
103.95 (C-9a), 107.47 (C-4), 111.03 (C-8a), 120.60 (C-2Ј, C-6Ј),
121.57 (C-5), 124.83 (C-7), 125. 89 (C-4Ј), 125.89 (C-4Ј), 130.45 (C-
3Ј, C-5Ј), 132.10, 132.97 (C-4a, C-10a), 149.29 (C-6), 153.97 (C-1Ј),
164.67, 163.91, 167.69 (CϪOH), 181.15 (C-10), 190.51 (C-9) ppm.
¯
Crystallographic Data. 4d: Crystal system: triclinic; space group P1;
˚
˚
˚
a ϭ 8.088(1) A, b ϭ 9.759(1) A, c ϭ 14.451(1) A, α ϭ 76.13(1)°,
3
˚
3-(2,6-Dimethylphenoxy)-1,8-dihydroxy-2-iodo-6-methylanthra-
quinone (4b): Yield 160 mg (32%), m.p. 302Ϫ304 °C, yellow plates.
UV (acetone): λmax. ϭ 436 nm. IR (KBr)1: ν˜ ϭ 3425, 1663, 1633,
1522 cmϪ1. MS calculated for C23H17IO5 [M]: 500.29, MALDI-MS
βϭ 75.24(1)°, γ ϭ 70.40(1)°, V ϭ 1024.1(2) A , Z ϭ 2, ρcalcd.
ϭ
1.668 g·cmϪ3, collected reflections 6504; unique reflections 4697;
number of parameters 347; R1 ϭ 0.0340; wR2 0.0800 for [I Ͼ 2σ(I)].
˚
¯
4e: Crystal system: triclinic; space group P1; a ϭ 6.898(1) A, b ϭ
1
[M ϩ Na]ϩ found: 523.3. H NMR (CDCl3): δ ϭ 2.13 (s, 6 H, 2Ј-
˚
˚
8.513(1) A, c ϭ 18.367(2) A, α ϭ 88.94(1)°, β ϭ 84.53(1)°, γ ϭ
73.25(1)°, V ϭ 1028.0(2) A , Z ϭ 2, ρcalcd. ϭ 1.707 g·cmϪ3, col-
3
˚
CH3, 6Ј-CH3), 2.44 (s, 3 H, 6-CH3), 6.78 (s, 1 H, 4-H), 7.10 (s, 1
H, 7-H), 7.16 (s, 3 H, 3Ј-H, 4Ј-H, 5Ј-H), 11.94 (s, 1 H, 8-OH), 13.32
(s, 1 H, 1-OH) ppm. 13C NMR (CDCl3): δ ϭ 16.28, 22.27 (CH3),
84.13 (C-2), 104.62 (C-4), 110.89 (C-9a), 113.23 (C-8a), 121.46 (C-
5), 124.81 (C-7), 126.46 (C-4Ј), 129.48 (C-3Ј, C-5Ј), 130.64 (C-2Ј,
C-6Ј), 132.99, 135.23 (C-4a, C-10a), 149.13 (C-6), 150.48 (C-1Ј),
162.69, 163.64, 163.94 (C-OH), 181.53 (C-10), 190.67 (C-9) ppm.
lected reflections 5950; unique reflections 4323; number of para-
meters 364; R1 ϭ 0.0340; wR2 0.0800 for [I Ͼ 2σ(I)]. The structures
of 4d and 4e were solved by the direct method using the SHELXL-
97 program.[25] All hydrogen atoms were located and refined iso-
tropically, all non-hydrogen atoms were refined anisotropically.
CCDC-189425 and -189426 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the
Cambridge Crystallographic Data Centre, 12 Union Road, Cam-
bridge CB2 1EZ, UK; Fax: (international) ϩ 44-1223-336-033;
E-mail: deposit@ccdc.cam.ac.uk].
3-(3,5-Dimethylphenoxy)-1,8-dihydroxy-2-iodo-6-methylanthra-
quinone (4c): Yield 25 mg (5%), m.p. 252Ϫ254 °C, yellow plates.
UV (acetone): λmax. ϭ 437 nm. IR (KBr): ν˜ ϭ 3440, 1675, 1625,
1560 cmϪ1. MS calculated for C23H17IO5 [M]: 500.29, MALDI-MS
1
[M ϩ Na]ϩ found: 523.3. H NMR (CDCl3): δ ϭ 2.34 (s, 6 H, 3Ј-
CH3, 5Ј-CH3), 2.44 (s, 3 H, 6-CH3), 6.73 (s, 2 H, 2Ј-H, 6Ј-H), 6.91
(s, 1 H, 7-H), 7.10 (s, 1 H, 4-H), 7.13 (s, 1 H, 4Ј-H), 7.57 (s, 1 H,
4Ј-H), 11.94 (s, 1 H, 8-OH), 13.32 (s, 1 H, 1-OH) ppm.
Acknowledgments
1,8-Dihydroxy-2-iodo-6-methyl-3-(2,4,6-trimethylphenoxy)-
anthraquinone (4d): Yield 82 mg (16%), m.p. 257Ϫ258 °C, yellow
plates. UV (acetone): λmax. ϭ 437 nm. IR (KBr): ν˜ ϭ 3425, 2918,
1670, 1622, 1554 cmϪ1. MS calculated for C24H19IO5 [M]: 514.32,
MALDI-MS [M ϩ H]ϩ found: 515.3. 1H NMR (CDCl3): δ ϭ 2.07
(s, 6 H, 2Ј-CH3, 6Ј-CH3), 2.33 (s, 3 H, 3Ј-CH3), 2.44 (s, 3 H, 6-
CH3), 6.79 (s, 1 H, 4-H), 7.10 (s, 1 H, 7-H), 7.26 (s, 2 H, 3Ј-H, 5Ј-
H), 11.94 (s, 1 H, 8-OH), 13.32 (s, 1 H, 1-OH) ppm. 13C NMR
(CDCl3): δ ϭ 16.33, 21.02, 22.39 (CH3), 84.21 (C-2), 104.85 (C-4),
110.87 (C-9a), 113.38 (C-8a), 121.56 (C-5), 124.81 (C-7), 130.22 (C-
3Ј, C-5Ј), 130.30 (C-4Ј), 133.15, 135.32 (C-4a, C-10a), 136.08 (C-
2Ј, C-6Ј), 148.43 (C-6), 149.23 (C-1Ј), 162.80 (C-3), 164.04 (C-1, C-
8), 181.72 (C-10), 190.78 (C-9) ppm.
The authors are grateful to Fonds der Chemischen Industrie and
Deutsche Forschungsgemeinschaft (DFG) Graduiertenkolleg
‘‘Mechanistische und Anwendungsaspekte nichtkonventioneller
Oxidationsreaktionen’’ for financial support. We thank Prof.
Joachim Sieler for generating X-ray crystallographic data from 4e
and for technical support.
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anthraquinone (4e): Yield 121 mg (23%), m.p. 281Ϫ283 °C, yellow
plates. UV (CHCl3): λmax. ϭ 440 nm. IR (KBr): ν˜ ϭ 3440, 2920,
1670, 1625 cmϪ1. MS calculated for C25H21IO5 [M]: 528.35,
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2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
897