Transformations of Azidoanthraquinones
1639 1644
12 using restricted Hartree Fock method in half-electron approxima-
tography on silica gel (CHCl3) to afford 2-tert-butyl-5(2'-hydroxy-5'-tert-
butylphenyl)-naphtho[2,3-c]-phenoxazine-8,13-dione (6b; 0.04 g, 77%).
tion.[20]
Acylation of 2-tert-butyl-5(2'-hydroxy-5'-tert-butylphenyl)-naphtho[2,3-c]-
phenoxazine-8,13-dione (6b): The solution of phenoxazine 6b (0.05 g,
0.1 mmol) in a mixture of Ac2O (10 mL) and pyridine (5 mL) was stirred
for 1 h at 1008C and subsequently poured into water. The precipitate was
recrystallized from EtOH to afford 2-tert-butyl-5(2'-acetoxy-5'-tert-butyl-
phenyl)-naphtho[2,3-c]-phenoxazine-8,13-dione (6c; 0.044 g, 82%). M.p.
93 958C; IR (KBr): nÄ 2960, 1770, 1670 cmÀ1; UV/Vis (ethanol): l (lge)
263 (4.64), 540 (3.85); MS: m/z: calcd for C36H33NO5: 559.2412; found:
1-Aryloxy-2- and 4-azidoanthraquinones (3a,b and 8): A solution of
NaNO2 (0.83 g, 12 mmol) in HCl (30%, 3 mL) was added at room
temperature to a stirred solution of 1-aryloxy-2- or 4-aminoanthraquinone
(3.2 g, ꢁ10 mmol) in acetic acid (100 mL). The reaction mixture was stirred
for 1 h and then cooled to 108C and NaN3 (0.78 g, 12 mmol) was added.
Then the mixture was stirred for an additional 30 min in the dark. The
precipitated azide was filtered off. Purification by silica gel column
chromatography (CHCl3) afforded 3a (82%) and 3b (85%). 3a: m.p.
1648C (decomp); 1H NMR (200 MHz, CDCl3): d 6.84 7.35 (m, 5H;
OPh), 7.49 (d, J(H,H) 8.5 Hz, 1H; 3-H), 7.71 (m, 2H; 6-H, 7-H), 8.09 (m,
1H; 5-H), 8.22 (m, 1H; 8-H), 8.27 (d, J(H,H) 8.5 Hz, 1H; 4-H); IR
(KBr): nÄ 3077, 2113, 1673 cmÀ1; UV/Vis (ethanol): l (lge) 267 (4.59),
559.2466 [M ].
Thermolysis of azides 3a,b: The solutions of compound 3a (0.34 g, 1 mmol)
or 3b (0.4 g, 1 mmol) in DMSO or TEG (20 mL) were heated for 1 h at
1508C. Subsequently the reaction mixture was poured into water. The
precipitate was separated using column chromatography (benzene). For
3a: isolated products 4a (0.02 g, 5%), 5a (0.08 g, 28%), and 1-phenoxy-2-
aminoanthraquinone (0.05 g, 16%); for 3b: isolated products 4b (0.02 g,
6%), 5b (0.13 g, 35%), and 1-(p-tert-butylphenoxy)-2-aminoanthraqui-
none (0.07 g, 19%).
370 (3.78); MS: m/z: calcd for C20H11N3O3: 341.0798; found: 341.0806 [M ];
3b: m.p. 1618C (decomp); 1H NMR (200 MHz, CDCl3): d 1.28 (s, 9H;
tBu), 6.76 (d, J 9 Hz, 2H; 2'-H, 6'-H), 7.28 (d, J(H,H) 9 Hz, 2H; 3'-H, 5'-
H), 7.49 (d, J(H,H) 8.5 Hz, 1H; 3-H), 7.72 (m, 2H; 6-H, 7-H), 8.13 (m,
1H; 5-H), 8.23 (m, 1H; 8-H), 8.26 (d, J(H,H) 8.5 Hz, 1H; 4-H); IR
(KBr): nÄ 2990, 2109, 1670 cmÀ1; UV/Vis (ethanol): l (lge) 263 (4.57),
Thermolysis of azide 3b in the presence of p-tert-butylphenol: A solution
of azide 3b (0.04 g, 0.1 mmol) and p-tert-butylphenol (0.15 g, 1 mmol) in
DMSO (20 mL) was heated for 1 h at 1508C. The reaction mixture was
poured into water. The precipitate was separated by column chromatog-
raphy (CHCl3) to afford 6b (0.043 g, 85%).
375 (3.74); MS: m/z: calcd for C24H19N3O3: 397.2422; found: 397.2406 [M ].
Preparative photolysis of azides 3a and 3b: The solutions of 3a (0.34 g,
1 mmol) or 3b (0.4 g, 1 mmol) in benzene (500 mL) were irradiated by the
filtered light of a mercury lamp (l ꢀ 320 nm) for 7 8 h at 208C until the
complete conversion of the starting material (TLC control). The solvent
was evaporated and the residue was separated using a silica gel column
chromatography (benzene). 1-Hhydroxy-2-arylaminoanthraquinones
(4a,b) isolated from the first fractions were identified by comparison with
the samples synthesized as described in ref. [12] The product yields were
19% (4a) and 25% (4b). The neighboring fractions containing products 5
and 6 were doubly separated using column chromatography (CHCl3). The
yields were 15% (5a), 16% (5b), 23% (6a) and 28% (6b).
Thermolysis of azides 3a and 3b in the presence of KOH: Granulated
KOH (0.06 g, 1 mmol) was added to the stirred solutions of 3a (0.34 g,
1 mmol) or 3b (0.4 g, 1 mmol) in DMSO (30 mL) and solutions were kept
at room temperature for 10 h or at 508C for 1 h. The reaction mixture was
poured into water. The precipitate was filtered and dried to afford
compounds 4a or 4b with the yields of 95% each.
Photolysis of 1-(p-tert-butylphenoxy)-4-azidoanthraquinone (8): The start-
ing material azide 8 (purity ꢁ80%) was contaminated with 5-(p-tert-
butylphenoxy)anthra[9,1-cd]izoxazole-6-one (9). The solution of a mixture
of 8 and 9 (0.4 g, ꢁ1 mmol) in benzene (500 mL) was irradiated by a
mercury lamp (l ꢀ 320 nm) for 1 h at room temperature until the complete
conversion of the starting material (TLC control). The solvent was
evaporated and the residue was purified by column chromatography
(CHCl3) to afford 9 (0.33 g, ꢂ85%).
5H-Naphtho[2,3-c]-phenoxazine-8,13-dione (5a): m.p. 318 3218C;
1H NMR (200 MHz, [D6]DMSO): d 6.69 (m, 2H; 2-H, 3-H), 6.82 (d,
J(H,H) 8.5 Hz, 1H; 6-H), 6.92 (m, 2H; 1-H, 4-H), 7.70 (d, J(H,H)
8.5 Hz, 1H; 7-H), 7.74 (m, 2H; 10-H, 11-H), 8.27 (m, 2H; 9-H, 12-H),
9.05 (s, 1H; NH); IR (KBr): nÄ 3447, 2982, 1660, 1631 cmÀ1; UV/Vis
(ethanol): l (lge) 267 (4.58), 310 (3.62), 410 (3.18), 560 (3.83); MS: m/z:
calcd for C20H11NO3: 313.0736, found: 313.0743 [M ].
5-(p-tert-Butylphenoxy)anthra[9,1-cd]-izoxazol-6-one (9): m.p. 222
2248C; 1H NMR (20 MHz, CDCl3): d 1.28 (s, 9H; tBu), 6.76 (d,
J(H,H) 9 Hz, 2H; 2'-H, 6'-H), 7.28 (d, J(H,H) 9 Hz, 2H; 3'-H, 5'-H),
7.49 (d, J(H,H) 8.5 Hz, 1H; 3-H), 7.72 (m, 2H; 6-H, 7-H), 8.13 (m, 1H;
5-H), 8.23 (m, 1H; 8-H), 8.26 (d, J(H,H) 8.5 Hz, 1H; 4-H); IR (KBr): nÄ
2975, 1675, 1650 cmÀ1; UV/Vis (ethanol): l (lge) 248 (4.42), 306 (3.90),
442 (4.07), 457 (4.02); MS: m/z: calcd for C24H19NO3: 369.1365, found
2-tert-Butyl-5H-naphtho[2,3-c]-phenoxazine-8,13-dione (5b): m.p. 289
2928C; 1H NMR (200 MHz, CDCl3): d 1.23 (s, 9H; tBu), 6.81 (d,
J(H,H) 8.5 Hz, 1H; 3-H), 7.89 (d, J 8.5, 1H; 6-H), 7.09 (s, 1H; 1-H), 7.18
(d, J(H,H) 8.5 Hz, 1H; 4-H), 7.70 (d, J(H,H) 8.5 Hz, 1H; 7-H), 7.74 (m,
2H; 10-H, 11-H), 7.99 (s, 1H; NH), 8.23 (m, 2H; 9-H, 12-H); IR (KBr): nÄ
3457, 2962, 1651, 1629 cmÀ1; UV/Vis (ethanol): l (lge) 265 (4.46), 313
(3.60), 412 (3.25), 567 (3.79); MS: m/z: calcd for C24H19NO3: 369.1365;
369.1365 [M ].
Thermolysis of 1-(p-tert-butylphenoxy)-4-azidoanthraquinone (8): The
solution of a mixture of 8 and 9 (0.4 g, ꢁ1 mmol) in DMSO (20 mL) was
heated for 1 h at 1508C. The solvent was evaporated and the residue was
purified by column chromatography (CHCl3) to afford izoxazole 9 (0.30g,
ꢁ80%).
found: 369.1371 [M ].
5(2'-Hydroxyphenyl)-naphtho[2,3-c]-phenoxazine-8,13-dione (6a): m.p.
185 1888C; IR (KBr): nÄ 3440, 2965, 1662 cmÀ1; UV/Vis (ethanol): l
(lge) 266 (4.70), 310 (3.61), 410 (3.42), 548 (4.03); MS:: calcd for
C26H15NO4: 405.1001; found: 405.0975 [M ].
2-tert-Butyl-5(2'-hydroxy-5'-tert-butylphenyl)-naphtho[2,3-c]-phenoxa-
zine-8,13-dione (6b): m.p. 192 1958C; 1H NMR (500 MHz, CDCl3): d
1.22 (s, 9H; tBu), 1.29 (s, 9H; tBu), 5.94 (d, J(H,H) 8.5 Hz, 1H; 3'-H), 5.99
(d, J(H,H) 8.5 Hz, 1H; 6-H), 6.68 (dd, J1(H,H) 8.5, J2(H,H) 3.0 Hz,
1H; 4'-H), 6.70 (d, J(H,H) 3.0 Hz, 1H; 6'-H), 7.14 (d, J(H,H) 3.0 Hz,
1H; 1-H), 7.18 (d, J(H,H) 8.5 Hz, 1H; 4-H), 7.31 (d, J(H,H) 8.5 Hz, 1H;
7-H), 7.44 (dd, J1(H,H) 8.5 Hz, J2(H,H) 3.0 Hz, 1H; 3-H), 7.59 (td,
J1(H,H) 8.0 Hz, J2(H,H) 2.0 Hz, 1H; 10-H), 7.66 (td, J1(H,H) 8.0 Hz,
J2(H,H) 2.0 Hz, 1H; 11-H), 7.75 (s, 1H; NH), 8.00 (dd, J1(H,H) 8.0,
J2(H,H) 2.0 Hz, 1H; 9-H), 8.05 (dd, J1(H,H) 8.0, J2(H,H) 2.0 Hz, 1H;
12-H); IR (KBr): nÄ 3400, 2960, 1660 cmÀ1; UV/Vis (ethanol): l (lge) 266
(4.78), 313 (3.63), 410 (3.46), 560 (4.02); MS: m/z: calcd for C34H31NO4:
Acknowledgement
Authors gratefully acknowledge
a financial support of the Russian
Foundation for Basic Research (projects 00-03-32728 and 01-03-32864).
[1] a) Y. E. Gerasimenko, N. T. Poteleschenko, Zh. Org. Chim. 1971, 7,
2413 2415; b) review: N. P. Gritsan, S. Klimenko, J. Photochem.
Photobiol. A: Chemistry 1992, 70, 103 117; c) N. P. Gritsan, Mol.
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Organic Photochromic and Thermochromic Compounds, Plenum
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[2] a) P. A. S. Smith in Azides and Nitrenes, Reactivityand Utility ,
Academic, New York, 1984, pp. 95 204; b) G. B. Schuster, M. S.
Platz, Adv. Photochem. 1992, 17, 69 143; c) N. P. Gritsan, E. A.
517.2253; found: 517.2241 [M ].
Photolysis of azide 3b in the excess of p-tert-butylphenol: The solution of
azide 3b (0.04 g, 0.1 mmol) and p-tert-butylphenol (0.03 g, 0.2 mmol) in
benzene (50 mL) was irradiated with a mercury lamp (l ꢀ 320 nm) for 8 h
at room temperature until the complete conversion of starting azide. The
solvent was evaporated and the residue was purified by column chroma-
Chem. Eur. J. 2003, 9, No. 7
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