SYNTHESIS OF ESTERS AND AMIDES
785
Table (Contd.)
Com-
Yield,
pound
%
Found, %
Calculated, %
mp, C*
1H NMR spectrum, , ppm
Formula
no.
C
H
N
C
H
N
XVIII 64 (b) 276 278
3.75 s (3H, OMe), 5.97 s (2H, 51.2 4.7 29.7 C10H11N5O2 51.5 4.8 30.0
NH2), 6.81 m (2H, arom.),
7.66 m (2H, arom.), 9.48 s
(1H, NH), 12.36 s (1H, NH)
* Compounds III and V were recrystallized from H O; IV, VI X, XII, XIII, and XV XVII, from EtOH; and XI, XIV, and XVIII,
2
from DMF.
** Published data, mp, C: III, 220 [10]; V, 247 [11]; VI, 156 158 [3].
substituents in the benzene ring, the desired amides
were not formed under the above conditions, and
under more severe conditions (heating to 150 C with-
out solvent or refluxing in DMF) an unseparable mix-
ture of products was obtained.
The mass spectra of all the compounds prepared
contain a strong peak of molecular ion.
EXPERIMENTAL
1
The H NMR spectra were recorded on a Varian
We managed to prepare the anilides by treatment of
Unity 300 spectrometer (300 MHz, DMSO-d , inter-
6
anilines with PCl followed by the reaction of the re-
3
nal reference TMS). The mass spectra were taken on
a Finnigan MAT-Incos 50 device with direct sample
inlet (electron impact, 70 eV). The melting points
were determined with a PTP device. The HPLC anal-
ysis was performed with a Milikhrom-5 chromato-
graph equipped with a UV detector and an 80 2-mm
sulting organophosphorus compound, without its iso-
lation, with acids I and II. By this procedure we pre-
pared compounds XIV XVIII [reaction (3), see table]:
PCl
3
RNH2
R N=P N R
Py
HN
H
N
O
column packed with Separon C ; the mobile phase
I, II
18
1
(3)
,
R
was methanol (flow rate 80 l min ). The detection
( )n
N
H2N
N
was performed at
210 nm.
H
XIV XVIII
Acids I and II were predried in a vacuum at 105
110 C for 24 h.
where n = 0 (XIV, XVI, XVIII), 1 (XV, XVII); R =
Ph (XIV, XV), p-ClC H (XVI, XVII), p-MeOC H
6 4
6
4
Esters of 5-amino-1,2,4-triazole-3-carboxylic
(III, V) and 5-amino-1,2,4-triazol-3-ylacetic (IV,
(XVIII).
The compositions and structures of the compounds
VI) acids. A 0.047-mol portion of SOCl was added
1
2
prepared were determined by elemental analysis, H
dropwise with stirring to a mixture of 0.047 mol of
acid I or II and 0.4 mol of anhydrous methanol or
ethanol. The mixture was heated to boil and refluxed
NMR spectroscopy, and mass spectrometry; their
purity was confirmed by HPLC.
The compounds obtained exhibit prototropy and
for 1 h, after which an additional 0.047 mol of SOCl
2
can exist in the form of tautomers A and B [equilib-
was added, and the refluxing was continued for 3 h
more. Excess alcohol was distilled off in a water-jet-
pump vacuum, and a saturated solution of sodium ace-
tate was added with cooling to the residue to pH 5 6.
The precipitate thus obtained was filtered off, washed
with water, and recrystallized.
1
rium (4)]. According to H NMR spectra, in DMSO
tautomer A prevails [ (NH ) 5.6 6.0 ppm, see table].
2
Minor amounts of tautomer B were detected in the
spectra of amides VII, IX, X, XIV, and XVIII (addi-
tional broadened singlet ot the amino group at 4.8
5.1 ppm). The chemical shifts of amino group protons
in tautomers A and B are consistent with published
data for other 3(5)-amino-1,2,4-triazoles [13].
Amides of 5-amino-1,2,4-triazole-3-carboxylic
(VII, IX, XI, XIII, XIV, XVI, XVIII) and 5-amino-
1,2,4-triazol-3-ylacetic (VIII, X, XII, XV, XVII)
acids. (a) A mixture of 0.1 mol of ester III VI,
0.02 mol of triethylamine, and 0.012 mol of aliphatic
amine was heated at 85 90 C for 3 h (synthesis of
XIII was performed in a sealed ampule), after which
triethylamine and excess aliphatic amine were distilled
H
N
HN
N
O
N
O
R
R
( )n
N
H2N
N
R
( )n
N
H2N
N
R
A
B
(4)
RUSSIAN JOURNAL OF APPLIED CHEMISTRY Vol. 79 No. 5 2006
Chernyshev
