730
PECHKIN et al.
2-(5-Acyl-2-furyl)-1-methylphenanthro[9,10-d]-
acid was heated for 0.5 h on a water bath. The mixture
was cooled, diluted with a small amount of cold
water, and neutralized with 25% aqueous ammonia,
and the precipitate of quinone Ig was filtered off.
1-Methyl-2-(5-nitro-2-furyl)phenanthro[9,10-d]-
imidazole (Il). Nitrating mixture, 10 ml (20 mmol),
was added dropwise with stirring at 20 25 C to
a solution of 2.98 g (10 mmol) of compound Ia in
20 ml of acetic anhydride. The mixture was then
stirred for 30 40 min, the progress of the reaction
being monitored by TLC. The product was isolated
as described above for compound Ie.
imidazoles Ib Id and 2-(5-acyl-2-thienyl)-1-methyl-
phenanthro[9,10-d]imidazoles IIb IId (general
procedure). A mixture of 2.98 g (10 mmol) of com-
pound Ia or 3.14 g (10 mmol) of compound IIa and
10 15 mmol of the corresponding acylating agent
(benzoic acid, acetic anhydride, or hexamethylene-
tetraamine) in 20 g of polyphosphoric acid was stirred
for 4 6 h at 110 130 C. The mixture was cooled,
diluted with 100 ml of cold water, and carefully
neutralized with 25% aqueous ammonia. The product
was extracted into chloroform (3 30 ml), the extract
was dried over CaCl2 and evaporated, and the residue
was purified by column chromatography on Al2O3
(15 2.5 cm) using chloroform as eluent.
2-(5-Bromo-2-furyl)-1-methylphenanthro-
[9,10-d]imidazole (Ie). A cold solution of 2.98 g
(10 mmol) of compound Ia in 20 ml of dichloroethane
was added with stirring over a period of 30 min to
a solution of 3.2 g (20 mmol) of bromine in 30 ml of
dichloroethane, cooled to 10 C. The mixture was
stirred for 1.5 h at 0 5 C, and Ie hydrobromide was
filtered off, washed 30 ml of dichloroethane, dried,
and neutralized with 25% aqueous ammonia.
1-Methyl-7-nitro-2-(5-nitro-2-thienyl)phenan-
thro[9,10-d]imidazole (IIl) was synthesized in
a similar way.
REFERENCES
1. Oleinikova, L.Ya. and Pozharskii, F.T., Khim. Getero-
tsikl. Soedin., 1972, no. 11, pp. 1014 1017.
2. Weidenhagen, R., Ber., 1936, vol. 69, no. 6, pp. 2263
2267.
3. Phillips, M.A., J. Chem. Soc. C, 1928, no. 12,
pp. 2393 2399.
7-Bromo-2-(5-bromo-2-thienyl)-1-methylphen-
anthro[9,10-d]imidazole (IIe) was synthesized in
a similar way.
4. Steck, E. and Day, A., J. Am. Chem. Soc., 1943, no. 6,
pp. 1548 1552.
5. Kikugava, Y., Synthesis, 1981, no. 2, pp. 124 125.
1-Methyl-2-(5-sulfo-2-furyl)phenanthro[9,10-d]-
imidazole (If) and 1-methyl-2-(5-sulfo-2-thienyl)-
phenanthro[9,10-d]imidazole (IIf). A mixture of
2.98 g (10 mmol) of compound Ia or 3.14 g
(10 mmol) of compound IIa and 0.98 g (10 mmol) of
sulfuric acid in 20 g of polyphosphoric acid was
stirred for 1 h at 60 80 C. The mixture was cooled
and diluted with 100 ml of cold water, and the precip-
itate was filtered off and recrystallized from alcohol.
1-Methyl-6,7-dihydrophenanthro[9,10-d]imid-
azole-6,7-dione (Ig). A mixture of 2.98 g (10 mmol)
of compound Ia or 3.14 g (10 mmol) of compound
IIa and 1.8 g of K2Cr2O7 in 10% aqueous sulfuric
6. El’chaninov, M.M., Oleinikova, L.Ya., and Simo-
nov, A.M., Khim. Geterotsikl. Soedin., 1979, no. 8,
pp. 1047 1049.
7. El’chaninov, M.M., Simonov, A.M., and Oleiniko-
va, L.Ya., Khim. Geterotsikl. Soedin., 1980, no. 1,
pp. 71 73.
8. Organic Reactions, Cope, A.C., Ed., New York:
Wiley, 1960, vol. 11. Translated under the title Orga-
nicheskie reaktsii, Moscow: Mysl’, 1965, vol. 11,
p. 199.
9. Churkin, Yu.D. and Savin, V.I., Khim. Geterotsikl.
Soedin., 1968, no. 2, pp. 369 372.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002
Pechkin
