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7. (a) Krassowska-Swiebocka, B.; Lulinski, P.; Skulski, L.
Synthesis 1995, 926–928; (b) Da´uria, M.; Mauriello, G.
Synthesis 1995, 248–250; (c) Sakamoto, T.; Kondo, Y.;
Yamanaka, H. Synthesis 1984, 252–254; (d) Giles, D.;
Parnell, E. W.; Renwick, J. D. J. Chem. Soc. (C) 1966,
1179–1184.
8. (a) Naidu, M. S. R.; Bensusan, H. B. J. Org. Chem. 1968,
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J.; Harrow, T. A.; Bible, Jr., R. H.; Finnegan, P. M.;
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Perkin Trans. 1 1983, 735–739; (f) Cliff, M. D.; Pyne, S.
G. Synthesis 1994, 681; (g) Zhang, X.; Yao, X.-T.; Dal-
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9. Papesch, V.; Burtner, R. R. J. Am. Chem. Soc. 1936, 58,
1314.
10. The addition of HCl must be slow and, if the pH is lower
than 10, the 4,5-diiodoimidazole will be contaminated
with a yellow solid.
11. A few drops of concentrated HCl were needed to ensure
complete solubilization of 2-phenylimidazole in the water.
12. The iodination of pyrazole was carried out at room
temperature. However, 2-methylimidazole was solubilized
in water at 80°C, prior to the addition of the solution of
KICl2.
13. Bass, R. J. Tetrahedron Lett. 1971, 1087–1088.
14. Kajigaeshi, S.; Kakinami, T.; Watanabe, F.; Okamoto, T.
Bull. Chem. Soc. Jpn. 1989, 62, 1349–1351.
15. Kajigaeshi and co-workers have found that this substrate
undergoes iodination using BTMAICl2 and ZnCl2 in
acetic acid although the reaction time is considerably
longer than that required for the ortho-methoxy-N-acet-
anilide, see reference 14.
16. We have found it possible to selectively mono- or di-iod-
inate substituted anilines (methyl, chloro, bromo, nitro or
carboxylic acid derivatives) as well as a number of pheno-
lic compounds such as salicylate derivatives, whereas
phenol readily yields 2,4,6-triiodophenol. A number of
activated aromatic compounds, particularly methoxyani-
lines or 1,2- and 1,4-dihydroxy- or hydroxymethoxy-ben-
zene derivatives were readily oxidized to dark intractable
products. Full details of these experiments will be made
available in due course.
19. All compounds were characterized spectroscopically and
new compounds gave satisfactory elemental and or high-
resolution mass analyses. Some representative data fol-
low: 4,5-Diiodoimidazole IR (w cm−1): 2794, 2586, 2362,
1507, 1376, 1248, 1155, 959; 1H NMR (MeOD-d4): l
7.92(s); 13C NMR: l 88.5, 142.8; HRMS: calc. 319.83075;
obs. 319.83025. 2-Phenyl-4,5-diiodoimidazole IR: 3103,
2960, 2863, 1491, 1458, 969, 705, 691; 1H NMR
(CD3OD): 8.00 (d, 2H, J 8.0), 7.75 (m, 3H); 13C NMR:
87.3, 126.6, 130.1, 130.7, 154.3; mass (m/z [% abun.]):
396(26), 304(26), 294(100), 254(31), 162(63), 127(61). 2-
Methyl-4,5-diiodoimidazole IR: 3112, 2994, 2848, 2714,
1
1547, 1387, 1186, 1019, 967, 856; H NMR (DMSO-d6):
2.37 (s, 3H), 12.55 (NH); 13C NMR (CD3OD): 14.0, 84.5,
152.6; HRMS: calc. 333.84640, obs. 333.84624. 4-Iodopy-
razole IR: 3287, 3112, 1050, 939, 597; 1H NMR
(CD3OD): 7.92 (s); 13C NMR: 81.0, 139.3, 143.2; HRMS:
calc. 193.93410, obs. 193.93411. 5-Iodoisatin IR: 3242,
3092, 1746, 1732, 1606, 1460, 1438, 1264, 1200, 1125, 834,
1
745, 670; H NMR (DMSO-d6): 6.75 (d, J 8.2), 7.76 (d, J
0.9), 7.88 (dd, J 0.9, 8.2), 11.10 (bs, NH); 13C NMR: 85.8,
115.1, 120.4, 132.9, 146.2, 150.4, 159.1, 183.5; mass:
273(53), 245(100), 217(19), 90(29). 5-Methyl-7-iodoisatin
IR: 3162, 3086, 2972, 2899, 1726, 1619, 1585, 1473, 1299,
1
1185, 1031, 1001, 943, 860, 768; H NMR (CDCl3): 2.32
(s, 3H), 7.39 (s), 7.72 (s), 7.86 (bs); 13C NMR (DMSO-
d6): 20.0, 78.5, 120.0, 124.9, 134.6, 147.0, 151.2, 160.4,
185.1; chem. anal. calc.: C, 37.66; H, 2.11; N, 4.88; found:
C, 37.75; H, 2.17; N, 4.79. 5-Iodo-2-methoxy-N-acetani-
lide IR: 3268, 3100, 1666, 1525, 1482, 1403, 1247, 1211,
1
1131, 1019, 798; H NMR (CDCl3): 2.19 (s, 3H), 3.85 (s,
3H), 6.60 (d, 1H, J 8.5), 7.32 (dd, 1H, J 1.3, 8.5), 7.69 (bs,
1H, NH), 8.69 (d, 1H, J 1.3); 13C NMR: 25.1, 56.1, 83.5,
112.0, 128.0, 129.2, 132.5, 147.6, 168.3; mass: 291(100),
249(81), 234(83), 206(15), 164(5), 79(31). 2,6-Diiodo-4-
nitroaniline 1H NMR (CDCl3/DMSO-d6): 6.13 (s), 8.45
(s); 13C NMR: 76.5, 133.5, 136.6, 151.4; chem. anal. calc.:
C, 18.48, H, 1.03, N, 7.18; found: C, 18.68, H, 1.24, N,
6.99.
20. Thorn, G. D.; Purves, C. B. Can. J. Chem. 1954, 32,
373–387.
21. Bui-Ho¨ı, Ng. Ph.; Jacquignon, P. Compt. rend. 1957, 244,
786–788; Chem. Abstr. 51:15519b. We observed that the
sample darkens at approx. 260°C. The mp of 5-iodoisatin
has been described as 264–265°C: Borsche, H. W.;
Fritzsche, A. Ber. 1924, 57B, 1770–1775; Chem. Abstr.
19:506.
17. For reviews on the chemistry of isatin, see: (a) Silva, J. F.
M.; Garden, S. J.; Pinto, A. C. Chemistry Preprint
Server, Elsevier, 2000, orgchem 0010004: http://
22. Sandin, R. B.; Drake, W. V.; Leger, F. Org. Synth. Coll.
Vol. 2, 1943, 196–197.
.