Impossibility of macrocyclization of resorcinol with the phenylphosphonous acid tetraethyldiamide

Article abstract of DOI:10.1134/S1070363210020088

On the basis of resorcinol and phenylphosphonous acid tetraethyldiamide a series of new phosphorylated compounds was prepared for the first time. It was found that on the basis of these products the target macrocycle does not form either under mild or under rigid conditions because instead of macrocyclization oligomerization takes place.

Full text of DOI:10.1134/S1070363210020088

ISSN 1070-3632, Russian Journal of General Chemistry, 2010, Vol. 80, No. 2, pp. 239–241. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © Yu.I. Blokhin, Yu.V. Volchenkova, K.N. Kornilov, A.V. Akilin, 2010, published in Zhurnal Obshchei Khimii, 2010, Vol. 80, No. 2,
pp. 213–216.
Impossibility of Macrocyclization of Resorcinol
with the Phenylphosphonous Acid Tetraethyldiamide
Yu. I. Blokhin, Yu. V. Volchenkova, K. N. Kornilov, and A. V. Akilin
Moscow State University of Technologies and Management,
Nikoloyamskaya ul. 30, Moscow, 109004 Russia
e-mail: orgchim@mail.ru
Received June 8, 2009
Abstract―On the basis of resorcinol and phenylphosphonous acid tetraethyldiamide a series of new
phosphorylated compounds was prepared for the first time. It was found that on the basis of these products the
target macrocycle does not form either under mild or under rigid conditions because instead of
macrocyclization oligomerization takes place.
DOI: 10.1134/S1070363210020088
Bis-phosphorylation of resorcinol I with the phenyl-
gives a mixture of bis- and monophosphorylated re-
sorcinols III and IV (δP 129.82 ppm) with the ratio of
signals 1.3:1 respectively, and small amount of starting
phosphamide II remains. Note that we observed the
formation of a mixture of mono- and bis-phos-
phorylated products in the reaction of resorcinol with
another phosphorylating agent, hexaethyl phosphoro-
triamidite at 1:2 ratio in acetonitrile [2].
phosphonous acid tetraethyldiamide II we carried out
recently [1].
OH
2PhP(NEt2)2
OH
31
Considering the obtained P NMR data and the re-
I
II
ported results [2] we have carried out bis-phos-
phorylation of resorcinol I with molar excess of phos-
phorylating agent II in boiling ethyl acetate for 2 h.
After the removing the solvent and the excess of
phosphonite II we have obtained pure compound III
without the admixture of the product IV. It is capable
of oxidation under the above-described conditions to
phosphonate V.
Ph
Ph
NEt2
OP
OP
NEt2
CH3COOEt, to
_2HNEt2
Ph
OP
OH
NEt2
III
IV
Ph
O
Analysis of 31P NMR spectra of the reaction pro-
ducts showed that while performing the reaction at
room temperature in ethyl acetate for 24 h (method 1)
bis-phosphorylation is incomplete. Ratio of the signals
belonging to the products III (δP 130.75 ppm) and II
(δP 97.93 ppm) is 1:2.2. Under heating the reaction
mixture to 60°C for 2 h and subsequent maintaining at
room temperature for 24 h (method 2) bis-phos-
phorylation proceeds more eagerly, ratio of signals of
the compounds III and II is 1.1:1 [1]. Refluxing of the
reaction mixture in the same solvent for 2 h and
maintaining for 24 h at room temperature (method 3)
OP
NEt2
O2
III
Ph
CH3COOEt
OP
O
NEt2
V
The oxidation of bis-phosphorylated resorcinol III
we carried out with the air oxygen according to the
procedure [3]. Diphenyl phosphonate V (δp 10.11 ppm)
was obtained for the first time. After crystallization
239

240
BLOKHIN et al.
from hexane compound V is a glass-like substance
with mp 53–54°C. Its composition and molecular mass
were confirmed by mass spectrometry.
vacuum at 90–100°C at the homogenous state of the
reaction mixture.
Bis-phosphorylation in a bulk under the established
conditions seems to be the most convenient procedure
for preparing compound III because it permits to avoid
the excess of phosphorylating agent, formation of the
side product IV, and also oxidation of trivalent
phosphorus derivatives.
Compound III we also synthesized under the other
conditions by the reaction of starting substances I and
II in 1:2 molar ratio at elevated temperature without a
solvent. Note that such reaction was carried out
recently with hydroquinone [4].
Performing the reaction in a bulk at elevated
temperature (145°C) did not lead to the expected
results because in this case only the oligomeric and
oxidated products are formed. Considering this fact we
have carried out this reaction in a water-jet pump
Sulfuration of the reaction mixture containing the
compounds III and IV obtained by means of the third
procedure as it was noted already in [1] gave a mixture
of thionophosphonates VI and VII with δp 77.41 and
77.14 ppm respectively.
Ph
Ph
S
S
OP
OP
NEt2
NEt2
S
III + IV
C6H6
Ph
S
OP
OH
NEt2
We managed to separate compound VI from the
substance VII by means of column chromatography.
Structure of the product VI was confirmed by MALDI
mass spectrometry and 1H NMR spectroscopy.
tetraethyldiamide II, we performed this reaction under
rigid conditions. As is known the boiling of phos-
phonite II with 2,2'-di(p-hydroxyphenyl)propane in o-
xylene for 7 h at the 1:1 molar ratio and the con-
centration no more than 0.2 mol l–1 leads to the
macrocyclic product [6].
We have established that in all the three above-
presented synthetic procedures at the addition of
starting bisphenol I to the reaction mixture containing
the compound III no formation of corresponding
macrocyclic products on the basis of phenylphos-
phonic acid tetraethyldiamide takes place.
We have found that boiling of a solution of com-
pounds I and II in o-xylene under the above-described
conditions [6] for 3 h under argon after removing of
solvent in a vacuum yields a light yellow paste.
Analysis of its 31P NMR spectrum shows that macro-
cyclization does not take place. Instead of that
oligomeric products (δP 157.94 ppm, broad signal) are
formed. They are eagerly oxidized in air to give the
mixture of substances giving a broad signal with δP
14.05 ppm. The formation of such products is
explained evidently by the fact that under the condi-
tions described diethylamide group on phosphorus still
enters the reaction with the OH groups of bis-phenol.
But because of the above-reported stereoelectronic
effect of phenyl substituents bis-phosphorylated re-
sorcinol III is incapable of the reaction with one more
molecule of the starting bis-phenol.
Instead of that in the presence of residues of the un-
reacted phenylphosphonite accumulation of mono-
phosphorylated resorcinol IV takes place. In the
absence of the residual compound II no additional
interactions were observed. The absence of macro-
cyclization may be explained firstly by the inertness of
the single diethylamino group on phosphorus to the
OH group of bisphenol [5]. Besides, inertness of both
diethylamido groups of the product III in this case is
caused by strong stereoelectronic effect of bulky
phenyl substituents on phosphorus which impede the
reaction of substrate with the molecule of resorcinol.
In extension of [1] where we for the first time
mentioned that no macrocyclization took place in the
reaction of resorcinol I with phenylphosphonous acid
Hence, no formation of the desired macrocycle on
the basis of resorcinol I and phenylphosphonous acid
tetraethyldiamide II takes place either under the
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 2 2010

IMPOSSIBILITY OF MACROCYCLIZATION OF RESORCINOL
241
Xylene
to
in 10 ml of ethyl acetate was refluxed in an open air
for 1 h. Solvent was removed in a vacuum, and the
obtained viscous paste was heated in boiling hexane,
cooled, and the isolated viscous mass was dried in a
vacuum (2 h, 50°C, 10 mm Hg). Compound VII was
obtained as a solid light yellow glass, yield 1.59 g
(98% in 2 stages), Rf 0.89 (C), δP 10.11 ppm, mp 53–
54°C. Found, %: P 12.43. C26H34N2O4P. Calculated,
%: P 12.40. [M + H]+ 500.96.
oligomeric products
I + II
O2
oxygen products.
conditions of molecular assembly or under direct
phosphorylation in ethyl acetate (mild conditions) and
in o-xylene (rigid conditions).
Product III obtained for the first time can be
probably used for macrocyclization with other bis-
phenols to give unsymmetrical macrocycles, the
promising substrates for constructing supramolecular
systems [7].
1,3-bis(Diethylamidophenylthiophosphonatoxy)-
benzene (VI). To a solution of 0.51 g of resorcinol I in
20 ml of ethyl acetate 2.35 g of tetraethyldiamido-
phenylphosphonite II was added with stirring at room
temperature. The reaction mixture was refluxed under
argon for 2 h and then left for 24 h. Solvent was
removed in a vacuum, and the product containing two
signals at 130.75 and 129.82 ppm in 31P NMR
spectrum was treated with 0.3 g of sulfur in 20 ml of
benzene. The reaction mixture was kept for 24 h at
room temperature and then subjected to chromato-
graphy on a column, elution with benzene. The product
was dried in a vacuum (2 h, 50°C, 10 mm Hg), and
compound V was obtained as a solid light yellow
paste, yield 2.45 g (34% in 2 stages), Rf 0.79 (B), δP
74.41 ppm. 1H NMR spectrum: 0.99 t (12H, CH3), 3.32
EXPERIMENTAL
Mass spectrum was obtained on a Bruker Daltonics
Autoflex II instrument equipped with the nitrogen laser
(λ 337 nm) under the regime of positive ion
registration. 31P NMR spectra of compounds III and
VII in ethyl acetate and of compound VI in benzene
were taken on a Bruker WP-80GY (32.4 MHz)
1
spectrometer against 85% phosphoric acid. H NMR
spectrum of compound V was obtained on a Bruker
AM-400 spectrometer (400 MHz) in deuterated
acetone against TMS.
3
m (8H, CH2, JHP 10.4 Hz), 7.17 s (1H, CH), 7.36 m
All the operations with trivalent phosphorus
compounds were carried out under dry argon. Column
chromatography was carried out on the L 100/250
silica gel. TLC was performed on Silufol plates using
1:2 hexane–dioxane (A), 3:1 hexane–dioxane (B), and
5:1 chloroform–ethanol (C) systems, development by
the iodine vapor or calcination.
(2H, CHp), 7.50 d (6H, CHo), 7.96 m (5H, CHm).
Found, %: P 11.73. C26H34N2O2P2S2. Calculated, %: P
11.65. [M + K]+ 572.12.
REFERENCES
1. Volchenkova, Yu.V., Kornilov, K.N., Blokhin, Yu.I.,
Abstarct of Papers, 15th Int. Conf. on Phosphorus
Chemistry, St. Petersburg, 2008, p. 379.
Tetraethyldiamidophenylphosphonite (II) was pre-
pared according to [8].
2. Nifant’ev, E.E., Rasadkina, E.N., and Yankovich, I.V.,
1,3-bis(Diethylamidophenylphosphonyloxy)benzene
(III). Tetraethyldiamidophosphonite II, 1.63 g, was
added with stirring to 0.36 g of resorcinol. The flask
with the reaction mixture was evacuated with a water-
jet pump and heated until the formation of the
homogenous liquid mass (90–100°C) and kept under
these conditions for 2 h. After that it was cooled, and
the water-jet pump was disconnected. Crude product
III was obtained as a thermoplastic glass-like light
yellow mass, Rf 0.51(A), δP 130.75 ppm, [M + H]+
469.25.
Zh. Obshch. Khim., 1997, vol. 67, no. 11, p. 1812.
3. Kornilov, K.N., and Blokhin, Yu.I., Izv. Vyssh. Uch.
Zaved., Ser. Khim., Khim. Tekhnol., 2007, no. 11, p. 23.
4. Blokhin, Yu.I., Gusev, D.V., and Galiaskarova, F.M.,
Zh. Obshch. Khim., 1995, vol. 65, no. 2, p. 209.
5. Nifant’ev, E.E., Usp. Khim., 2007, no. 4, p. 362.
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Khim., 1996, no. 9, p. 2369.
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p. 3.
8. Andreev, N.A. and Grishina, O.N., Zh. Obshch. Khim.,
1,3-bis(Diethylamidophenylphosphonatoxy)ben-
zene (V). A solution of 1.49 g of crude compound III
1979, vol. 49, no. 10, p. 2230.
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