Chemistry of Heterocyclic Compounds, Vol. 37, No. 6, 2001
HETEROCYCLIZATION OF DERIVATIVES
OF 4-OXOALKANOIC ACIDS TO
1,5-DISUBSTITUTED PYRROLIN-2-ONES
A. Yu. Egorova, V. A. Sedavkina, and Z. Yu. Timofeeva
Conditions were developed for the synthesis and production of 1-aryl-5-alkyl(aryl)-3H- and 1-aryl-5-
alkyl(aryl)-5H-pyrrolin-2-ones from the amides and esters of 4-oxoalkanoic acids. It was established
that the yield and ratio of the 3H and 5H isomers depend on the substrate employed in the reaction.
Keywords: 4-oxoalkanamides, 1-aryl-5-alkyl(aryl)-3H-pyrrolin-2-ones, 1-aryl-5-alkyl(aryl)-5H-
pyrrolin-2-ones, 4-oxoalkanoic esters.
Unsaturated five-membered nitrogen-containing 2-oxo heterocycles occupy an important place in
organic chemistry in connection with their discovery in the form of fragments of natural compounds and also the
production of substances with various types of biological activity from them [1]. The production of
1,5-disubstituted pyrrolin-2-ones in the reactions of N-substituted succinimides with the Grignard reagent and of
L-angelicolactone with primary amines has been described [2, 3].
The present paper gives the results of the synthesis of 5-alkyl(aryl)-3H- and 5-alkyl(aryl)-5H-pyrrolin-2-
ones from the amides and esters of 4-alkanoic acids and also the internal esters of these acids — 3H-furan-2-
ones — by their reaction with amines of the aromatic series under various conditions.
5-Alkyl(aryl)-3H-furan-2-ones (1a-g) react with primary aromatic amines (aniline, p-toluidine,
p-bromoaniline) in xylene solution at 120°C with the reagents in a ratio of 1:3 and form mixtures of 1-aryl-5-
alkyl(aryl)-3H-pyrrolin-2-ones (2a-g) and 1-aryl-5-alkyl(aryl)-5H-pyrrolin-2-ones (3a-f). The products were
isolated mainly in the form of the 3H isomers of 1,5-disubstituted pyrrolin-2-ones 2a-g (yields 70-75%). The
amounts of compounds 3a-f in the reaction mixtures were insignificant.
120 oC
+
+
H2N Ar
O
R
O
R
R
O
N
xylene
O
N
1a–g
Ar
Ar
3a–g
2a–g
O
80 oC
O
(CH3CO)2O
RCCH2CH2C
benzene
NHAr
4e,f,h
1-4 a R = CH3, Ar = C6H5; b R = C4H9, Ar = C6H5; c R = i-C4H9, Ar = C6H5;
d R = C5H11, Ar = C6H5; e R = C6H13, Ar = C6H5; f R = C7H15, Ar = C6H5;
g R = C6H5, Ar = C6H4CH3-p; h R = C7H15, Ar = C6H4Br-p
__________________________________________________________________________________________
N. G. Chernyshevskii Saratov State University, Saratov, Russia; e-mail: TimofijiwaSU@info.sgu.ru.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 755-758, June, 2001. Original article
submitted June 11, 1999. Revision submitted June 22, 2000.
694
0009-3122/01/3706-0694$25.00©2001 Plenum Publishing Corporation