KINETICS AND MECHANISM OF THE PUDOVIK REACTION... : II.
875
70% of ester VIII and 30% of phosphite II. However,
distillation gave a fraction [bp 75 76 C (0.5 mm), nD20
1.4135] containing, apart from ester VIII (64%),
phosphite II (30%) and phosphorous acid (6%).
Heating solutions of I or II in 2-propanol without (run
no. 31) and with (run no. 32) addition of the obtained
fraction revealed catalytic action of the additive, but
the purity of the experiment was disturbed by the
presence of phosphoric acid in the additive. The
catalytic action of ester VIII is also confirmed by the
fact that the reaction of azomethine I with phosphite
II handled for several days after purification and con-
taining some ester VIII formed by hydrolysis, too,
gives aminophosphonate IV (run no. 33, cf. run
nos. 22 and 23).
had been passed, analyzed by 31P NMR and IR spec-
troscopy.
The solvents were purified by known procedures
[11, 12].
Commercial benzalaniline was twice recrystallized
from 2-propanol and dried in a vacuum. Commercial
dimethyl phosphite and diisopropyl phosphite ob-
tained by a known procedure were twice distilled in a
vacuum and then twice distilled over metallic sodium
under argon.
Benzalanilinium phosphite (III). A solution of
1.6 g of phosphorous acid in 15 ml of 2-propanol was
added to a solution of 3.3 g of azomethine I in 20 ml
of 2-propanol. Some minutes after, crystals formed
and were filtered off (0.6 g). The mother liquor was
reduced in part to obtain an additional 1.8 g of the
reaction product (total yield 49%), mp 154 180 C. IR
Since acidic admixtures catalyze the reaction, we
proposed that basic additives would produce the
opposite effect. Actually, addition of triethylamine
(IX) or diethylaniline (X) to phosphite II handled as
described above much decreased the yield of amino-
phosphonate IV (run nos. 33 36).
1
spectrum, , cm : 1095, 1150 (POO ), 1633 (C=N),
2000 3000 br (P OH, P H, NH+). 31P NMR spectrum
(2-propanol), P, ppm: 1.6 d (1JPH 664.2 Hz).
ACKNOWLEDGMENTS
Thus, individual phosphite II in the absence of
catalysts does not form adducts with azomethine I.
Presumably, individual dialkyl phosphites are indif-
ferent toward compounds with C=N and, not un-
likely, C=O bonds. For instance, we could effect
addition of phosphite VII to benzalacetone by the
carbonyl group only under conditions of acid catalysis
[9]. However, Arbuzov et al. could obtain the adduct
in the absence of catalysts [10], by handling the reac-
tion mixture for a long time. This result can be ex-
plained by partial hydrolysis of phosphite VII as a
result of its unavoidable contact with air moisture.
The work was financially supported by the Russian
Foundation for Basic Research (project no. 99-03-
32880) and the Materialy i tekhnologii XXI veka
Scientific and Educational Center, Kazan State Uni-
versity (grant no. REC-007 of the Basic Research and
Higher Education Russian American Collaborative
Program).
REFERENCES
1. Sobanov, A.A., Zolotukhin, A.V., Galkin, V.I., Cher-
kasov, R.A., and Pudovik, A.N., Zh. Obshch. Khim.,
2002, vol. 72, no. 7, p. 1141.
Obviously, the synthetic result of reactions of azo-
methines and, probably, carbonyl compounds with
dialkyl phosphites depends on the purity and the time
of handling of the latter, since, because of contact
with air moisture and subsequent hydrolysis we most
probably dial here with a catalytic process.
2. Vorkunova, E.I. and Levin, Ya.A., Abstracts of
Papers, Nauchnaya sessiya posvyashchennaya
pamyati prof. I.M. Shermergorna (Scientific Session
Dedicated to the Memory of Prof. I.M. Shermergorn),
Kazan, 1997, p. 32.
EXPERIMENTAL
3. Bel’skii, V.E., Motygullin, G.Z., Eliseenkov, V.N.,
and Pudovik, A.N., Izv. Akad. Nauk SSSR, Ser. Khim.,
1969, no. 6, p. 1297.
The IR spectra were obtained on a Specord M-80
instrument for suspensions in mineral oil. The 31P
NMR spectra were recorded on a Varian Unity-300
instrument (121 MHz), external reference 85%-naya
H3PO4.
4. Ovchinnikov, V.V., Sobanov, A.A., and Pudovik, A.N.,
Dokl. Ross. Akad. Nauk, 1993, vol. 333, no. 1, p. 48.
5. Witkop, B., Patrick, J.B., and Kissman, H.M., Chem.
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6. Kim, T.V., Ivanova, Zh.M., and Gololobov, Yu.G.,
Zh. Obshch. Khim., 1978, vol. 48, no. 5, p. 1176.
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Lebedev, V.B., Zh. Obshch. Khim., 1986, vol. 56,
no. 12, p. 2702.
The thermograms were obtained on a home-made
installation with electronic recording, heating rate
5 deg/min, chromel alumel thermocouples, reference
mineral oil. The reaction mixtures (0.5 g) were placed
in Stepanov vessels and, after the exothermic effect
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 73 No. 6 2003