Recyclization of 4,5-Di(methoxycarbonyl)-1H-pyrrole-2,3-dione effected by monosubstituted hydrazines

Full text of DOI:10.1134/S107042801108029X

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2011, Vol. 47, No. 8, pp. 1265−1266. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © P.S. Silaichev, M.A. Chudinova, A.N. Maslivets, 2011, published in Zhurnal Organicheskoi Khimii, 2011, Vol. 47, No. 8, pp. 1245−1246.
SHORT
COMMUNICATIONS
Recyclization
of 4,5-Di(methoxycarbonyl)-1Н-pyrrole-2,3-dione
Effected by Monosubstituted Hydrazines
P. S. Silaicheva,b, M. A. Chudinovab, and A. N. Maslivetsa,b
aInstitute of Natural Sciences at Perm State University, Perm, Russia
bPerm State University, Perm, 614990 Russia
e-mail: koh2@psu.ru
Received December 24, 2010
DOI: 10.1134/S107042801108029X
Reactions of 4,5-di(alkoxycarbonyl)-1Н-pyrrole-2,3-
diones with hydrazine derivatives were not described.
keto carbonyl group of the arylcarbamoyl fragment with
water liberation.
By boiling for 20–30 min (TLC monitoring) in
a mixture of anhydrous benzene and 1,4-dioxane, 2 :
1, 1-(4-methylphenyl)-4,5-bis(methoxycarbonyl)-1Н-
pyrrole-2,3-dione (I) with benzyl- and phenylhydrazines
(IIa, IIb) in 1 : 1 ration we obtained in good yields dimethyl
1-benzyl- and 1-phenyl-5-(4-methylphenylcarbamoyl)-
1Н-pyrazole-3,4-dicarboxylates IIIа, IIIb.
The described reaction is an example of the recycli-
zation of pyrrolediones under the action of hydrazines,
i.e., the opening of the pyrroledione ring followed by the
closure of the pyrazole ring.
Dimethyl 1-benzyl-5-[(4-methylphenyl)
carbamoyl]-1Н-pyrazole-3,4-dicarboxylate (IIIа).
To a solution of 1.0 mmol of pyrroledione I in 10 ml of
anhydrous benzene was added a solution of 1.0 mmol
of benzylhydrazine (IIа) in 10 ml of anhydrous ben-
zene, 10 ml of 1,4-dioxane was added, and the mixture
was boiled for 20 min. The solvent was removed, the
residue was dissolved in boiling ethanol, cooled, the
separated precipitate was filtered off and recrystallized
The formation of compounds IIIа, IIIb occurs evi-
dently due to the addition of the primary amino group of
monosubstituted hydrazine to the atom С5 of pyrroledione
I, the opening of the pyrroledione ring at the N1–C5 bond
followed by the nucleophilic attack by the secondary
amino group of the monosubstituted hydrazine on the
MeOOC
MeOOC
O
RNHNH2
IIа, IIb
MeOOC
MeOOC
RNHNH
OH
O
O
N
N
C6H4Me-4
-4
C6H4Me
I
MeOOC
COOMe
MeOOC
MeOOC
OH
-4
N
CONHC6H4Me
N NHR
-4
CONHC6H4Me
_H2O
N
R
IIIа, IIIb
R = Bz (а), Ph (b).
1265

SILAICHEV et al.
1266
from ethanol. Yield 76%, mp 140–141°С. IR spectrum, ν,
cm–1: 3310 (NH), 1748 (СООMе), 1701 (СООMе), 1655
(СОNH). 1Н NMR spectrum, δ, ppm: 2.28 s (3H, Me),
3.70 s (3H, COOMe), 3.85 s (3H, COOMe), 5.49 s (2H,
CH2), 7.18 d (2H, С6H4, J 8.3 Hz), 7.27–7.36 m (5H, Ph),
7.51 d (2H, С6H4, J 8.3 Hz), 10.80 s (1H, NH). Found,
%: C 64.81; H 5.22; N 10.24. С22H21N3О5. Calculated,
%: C 64.86; H 5.20; N 10.31.
trum, δ, ppm: 20.37 (Me), 52.15 (OMe), 52.64 (OMe),
119.71–141.17 (Carom, C4, C5), 143.41 (C3), 156.30
(COOMe), 160.92 (CONH), 161.79 (COOMe). Found,
%: C 64.17; H 4.79; N 10.62. С21H19N3О5. Calculated,
%: C 64.12; H 4.87; N 10.68.
IR spectra of compounds obtained were recorded on
a spectrophotometer FSM -1201 from mulls in mineral
1
oil. Н and 13C NMR spectra were registered on a
spectrometer Bruker AM-400 [400 (1Н) and 100 (13С)
MHz] in DMSO-d6, internal reference TMS.
Dimethyl 5-[(4-methylphenyl)carbamoyl]-1-
phenyl-1Н-pyrazole-3,4-dicarboxylate (IIIb) was
obtained similarly. Yield 72%, mp 219–220°С (ethanol).
IR spectrum, ν, cm–1: 3300 (NH), 1736 (СООMе), 1698
ACKNOWLEDGMENTS
1
(СООMе), 1676 (СОNH). Н NMR spectrum, δ, ppm:
2.26 s (3H, Me), 3.75 s (3H, MeO), 3.91 s (3H, MeO),
7.15 d (2H, С6H4, J 8.4 Hz), 7.41 d (2H,С6H4, J 8.4 Hz),
7.50–7.61 m (5H, Ph), 10.94 s (1H, NH). 13С NMR spec-
The study was performed under the financial support
of the Ministry of Education and Science of the Russian
Federation (project 2.19.10).
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 8 2011