N-sulfonyl-and N-phosphorylbenzimidoylphosphonates

Article abstract of DOI:10.1134/S1070363206080068

A procedure for preparing N-sulfonyl-and N- phosphorylbenzimidoylphosphonates by oxidation of the corresponding α-(sulfonylamino)-and α-(phosphorylamino)benzylphosphonates was developed. The σ constants of imidoylphosphonate groups were evaluated by ¹⁹F NMR spectroscopy, and specific features of their electronic effects were considered. The reactions of the imidoylphosphonates obtained with O-, S-, P-, and N-nucleophiles were studied. The phosphonate-phosphoramidate rearrangement of α-aminobenzylidene-bisphosphonates was found. Nauka/Interperiodica 2006.

Full text of DOI:10.1134/S1070363206080068

ISSN 1070-3632, Russian Journal of General Chemistry, 2006, Vol. 76, No. 8, pp. 1210 1218.
Pleiades Publishing, Inc., 2006.
Original Russian Text N.V. Kolotilo, A.A. Sinitsa, Yu.V. Rassukanaya, P.P. Onys’ko, 2006, published in Zhurnal Obshchei Khimii, 2006, Vol. 76, No. 8,
pp. 1260 1268.
N-Sulfonyl- and N-Phosphorylbenzimidoylphosphonates
N. V. Kolotilo, A. A. Sinitsa, Yu. V. Rassukanaya, and P. P. Onys’ko
Institute of Organic Chemistry, National Academy of Sciences of Ukraine,
ul. Murmanskaya 5, Kiev, 02094 Ukraine
e-mail: onysko@rambler.ru
Received June 6, 2005
Abstract A procedure for preparing N-sulfonyl- and N-phosphorylbenzimidoylphosphonates by oxidation
of the corresponding -(sulfonylamino)- and -(phosphorylamino)benzylphosphonates was developed. The
constants of imidoylphosphonate groups were evaluated by 19F NMR spectroscopy, and specific features of
their electronic effects were considered. The reactions of the imidoylphosphonates obtained with O-, S-, P-,
and N-nucleophiles were studied. The phosphonate phosphoramidate rearrangement of -aminobenzylidene-
bisphosphonates was found.
DOI: 10.1134/S1070363206080068
Azomethines with activating electron-withdrawing
sulfonyl and phosphoryl substituents at nitrogen are
widely used in organic synthesis, in particular, for
preparing chiral derivatives. C-Phosphorylated imines
(imidoylphosphonates) are especially attractive as
convenient precursors of -amino phosphoryl deriva-
tives exhibiting a set of useful properties [1 4]. At
the same time, only a few representatives of N-phos-
phorylbenzimidoylphosphonates [5, 6] were described,
whereas N-sulfonylbenzimidoylphospohonates as well
as aryl imidoylphosphonates remained unknown up
to our studies [7, 8].
Scheme 1.
O
H
O=P(OR)2
ArCHO + (RO)2P
X
+ H2N X
Ar
N
H
H
Ia Id, IIa IId
Py Cl2
O=P(OR)2
X
O=P(OR)2
Py
X
Ar
N
C
Ar
N
Py HCl
H
l
IIIa IIId, IVa IVd
A
In this study we developed a synthetic route to
benzimidoylphosphonates containing sulfonyl or
phosphoryl substituent at nitrogen atom, considered
the electronic nature of the imidoylphosphonate group,
and examined some properties of the imines obtained.
I, III, X = SO2Ph, R = Et, Ar = 4-FC6H4 (a), 3-FC6H4
(b); R = Ph, Ar = 4-FC6H4 (c) [8], 3-FC6H4 (d) [8]. II, IV,
X = P(O)(OEt)2, R = Et, Ar = Ph (a); R = Ph, Ar =
4-ClC6H4 (b), Ar = 4-FC6H4 (c), 3-FC6H4 (d).
The key stage of our approach (Scheme 1) is the
oxidation of accessible sulfonyl- and phosphoryl-
aminobenzylphosphonates I and II with the Py Cl2
complex, probably involving initial chlorination of
the nitrogen atom [7 9]. Subsequent hydrogen chlo-
ride elimination in the intermediate amide A leads to
the formation of N-sulfonyl- (III) or N-phosphoryl-
imidoylphosphonates (IV) in high yields.
dry atmosphere but readily hydrolyzed with atmos-
pheric moisture. Spectral data for C-phosphorylated
amines confirm their structure. The signals of phos-
phorus at the imine carbon atom in the 31P NMR
spectra are observed in the range typical of imidoyl-
phosphonates [1] (3.6 4.0 ppm for ethyl and 5.2 to
6.4 ppm for phenyl esters). In going from N-phos-
phorylamino phosphonates II to imidoylphosphonates
IV, the coupling constant between the nonequivalent
phosphorus nuclei significantly increases (3JPC=NP
118 126 Hz). The IR spectra contain a strong band of
This approach allows preparation of both alkyl and
aryl imidoylphosphonates. Note that the reaction of
imidoyl chloride with phosphites, the most widely
used procedure for preparing imidoylphosphonates [1],
is inapplicable to preparation of the aryl esters.
1
C=N stretching vibrations (1610 1650 cm ). The
Imidoylphosphonates are liquids (IIIa, IIIb, IVa
IVd) or crystalline compounds (IIIc, IIId) stable in a
presence of the P C=N fragment is unambiguously
confirmed by the 13C NMR spectra containing the
1210

N-SULFONYL- AND N-PHOSPHORYLBENZIMIDOYLPHOSPHONATES
1211
Table 1. Chemical shifts of fluorinated benzenes XC6H4F and constants of N-substituted imidoylphosphonate (nos. 1 4)
and (amino)phosphorylalkyl (nos. 5 8) groups
F(XC6H4F)
Run
no.
X
I
R
t
3-F
4-F
1
2
3
4
5
6
7
8
PhSO2N=C[P(O)(OEt)2]
PhSO2N=C[P(O)(OPh)2]
(EtO)2P(O)N=C[P(O)(OPh)2]
PhCH2N=C[P(O)(OEt)2]
(EtO)2P(O)NHCH[P(O)(OPh)2]
PhSO2NHCH[P(O)(OPh)2]
PhSO2NHCH[P(O)(OEt)2]
PhSO2NHCH[P(O)Ph2]
2.09
2.48
2.05
1.80
1.07
0.95
0.26
0.15
7.42
8.53
7.42
2.38
0.03
0.14
0.52
1.08
0.38
0.43
0.37
0.34
0.24
0.22
0.12
0.06
0.18
0.21
0.18
0.02
0.04
0.03
0.03
0.03
0.56
0.64
0.55
0.36 [8]
0.20
0.17
0.09
0.09
characteristic signal of the imine sp2 carbon atom
is opposite compared to the imidoyl-containing groups
(nos. 2, 3). This fact may be due to the difference in
the NH acidity of the sulfonamide and phosphamide
groups. At the same time, the diphenylphosphinoyl-
containing substituent (no. 8) exhibits weak electron-
having a high direct coupling constant with phos-
1
phorus (
174.6 181.1 ppm, JPC 181 204 Hz).
C
N-Sulfonyl- and N-phosphorylimines, as a rule,
exhibit similar reactivity [10], although there are some
significant differences [11]. Using the sensitivity of
the fluorine nuclei to the electronic effects of sub-
stituents, we have quantitatively evaluated for the first
time the electronic effects of N-sulfonyl- and N-phos-
phorylimidoyl groups. From the chemical shifts of
fluorobenzimidoylphosphonates III and IV and the
corresponding aminoalkylphosphonates I and II,
measured against the internal fluorobenzene reference,
we evaluated, using the Taft equation [12, 13], the
inductive and resonance constants of N-substituted
imidoylphosphonate { C[P(O)(OR)2]=NX} and (phos-
phoryl)aminoalkyl { CH[P(O)(OR)2]NHX} groups.
donor properties (
0.09). In this connection, it
t
should be noted that the strong tendency of the
Ph2P(O) group in geminal aminobisphosphoryl com-
pounds to undergo C N phosphorotropic transfer is
attributed to its electron-donor properties [11, 14].
The difference in the electronic properties of the N-
sulfonyl- and N-phosphorylimine groups is probably
one of the factors responsible for different directions
of phosphorylation of these types of compounds
[7, 11].
Strong electron-withdrawing power of sulfonyl-
and phosphorylimidoylphosphonate groups causes
high reactivity of phosphorylated imines III and IV,
making it possible to readily carry out reactions un-
typical of nonactivated imidoylphosphonates. In par-
ticular, reactions with O- and S-nucleophiles occur
under mild conditions (benzene, 20 C), require no
catalyst, and yield adducts V VIII stable under
ambient conditions (Scheme 2).
The data obtained show (Table 1) that N-sulfonyl-
and N-phosphorylimidoylphosphonate groups are
fairly strong electron acceptors ( 0.55 0.64). In the
total electron-withdrawing effectt they significantly
exceed their N-benzyl analog (no. 4). The acceptor
effect of the imidoylphosphonate group depends on
the nature of substituents at the nitrogen atom
[PhSO2 > (EtO)2P(O) >> PhCH2] and of the phos-
phorus-containing group [(PhO)2PO > (EtO)2PO]. An
increase in the total acceptor effect in going from
N-benzyl (no. 4) to N-sulfonyl (no. 1) or N-phos-
phoryl substituent (no. 3) is mainly due to the res-
Thioglycolic acid adducts VIIa, VIIb, and VIIIa
do not tend to intramolecular cyclization to the cor-
responding thiazolidin-4-ones, contrary to their
analogs containing trihalomethyl group instead of the
aryl group [7].
onance component ( R), whereas
varies insignif-
I
icantly. This fact suggests higher polarizability of the
C=N bond in N-sulfonyl and N-phosphorylimines.
Note that substituted (amino)phosphorylalkyl groups
(nos. 5 7) also exhibit electron-withdrawing properties
The reaction of imines III and IV with hydrophos-
phoryl compounds allows preparation of N-sulfonyl
and N-phosphorylaminoarylidenebisphosphoryl
derivatives with the same (Xa, Xc) and different (IXa,
IXb, Xb) geminal phosphorus-containing groups at
the carbon atom. The reactivity of imidoylphospho-
nates toward hydrophosphoryl compounds increases
(
0.2, 0.17, and 0.09, respectively). The effect of
p
N-substituents on the variation of the electron-with-
drawing properties [(EtO)2P(O) > PhSO2] in this case
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

1212
KOLOTILO et al.
Scheme 2.
Scheme 3.
O=P(OR)2
O=P(OR)2
MeOH
X
P(OEt)2
Ar
eO
Ph
(EtO)2P
N
H
N
H
M
O
Va Vd, VI
O
R SH
Xa
O=P(OR)2
O=P(OR)2
X
X
O=P(OR)2
P(OEt)2
H
Ar
N
Ar
R
N
H
S
SiO2/I2, 20 C
Ph
N
IIIa IIId, IVa, IVb
VIIa,VIIb, VIIIa VIIIc
O
O=P(OEt)2
O=P(OR)2
X
R2 P(O)H
XI
Ar
N
H
P
R2
It is interesting that the rearrangement does not
take place when keeping a solution of bisphosphonate
Xa in the presence of iodine (benzene, 16 C, 15 h) or
of anhydrous hydrogen chloride, and also when treat-
ing a benzene solution of Xa with silica gel in the
absence of I2. A base catalyst (Et3N, refluxing in
benzene) favors the rearrangement, but in this case it
is accompanied by side processes.
O
IXa, IXb, Xa Xc
Va Vd, X = SO2Ph, R = Et, Ar = 4-FC6H4 (a), 3-FC6H4
(b); R = Ph, Ar = 4-FC6H4 (c), 3-FC6H4 (d). VI, X =
P(O)(OEt)2. VIIa, VIIb, X = SO2Ph, R = CH2COOH,
Ar = 4-FC6H4 (a), 3-FC6H4 (b). VIIIa VIIIc, X = P(O)
(OEt)2, Ar = Ph, R = CH2COOH (a), 4-ClC6H4 (b), H (c).
IXa, IXb, X = SO2Ph, R = Et, R = Ph, Ar = 4-FC6H4 (a),
R = R = Ph, Ar = 4-FC6H4 (b). Xa Xc, X = P(O)(OEt)2,
R = Et, R = EtO, Ar= Ph (a), R = Ph, R = EtO, Ar =
4-ClC6H4 (b), R = Ph, R = PhO, Ar= 4-ClC6H4 (c).
Thus, the C N phosphorotropic rearrangement
that we discovered previously [14] is a fairly general
reaction of -amino-gem-bisphoshoryl compounds
containing electron-withdrawing substituents at the
nitrogen atom. We also discovered the thermal C
N
with an increase in the electron-acceptor power of aryl
substituent (4-ClC6H4 > Ph) or of the phosphoryl
group at the azomethine carbon atom [(PhO)2PO >
(EtO)2PO].
phosphorotropic transfer in C,N-diphosphorylated
ketene aminals [15]. On the other hand, generation of
carbanions at the benzyl carbon atom of N-benzyl-
phosphoramidates PhCH2N(X)P(O)(OEt)2 with sec-
BuLi or i-Pr2NLi causes the N C migration of the
phosphoryl group with the formation of amino phos-
phonates [16]. Hence, phosphoramidates and amino
phosphonates tend to mutual transformations, which
should be taken into account in synthetic practice as
well as in evaluation of the biological activity of these
compounds.
Geminal bisphosphonates X are stable in a dry
atmosphere at room temperature, but heating causes
their decomposition along several pathways. Therefore,
these compounds were characterized without additional
purification; according to the 31P NMR data, they
contain about 10 15% impurities. Attempted TLC
purification of triphosphorylated adduct Xa on silica
gel, followed by development with iodine vapor,
causes irreversible 1,2-C N transfer of the phosphoryl
group with the formation of N,N-bisphosphorylated
aminobenzylphosphonate XI (Scheme 3). The struc-
ture of XI is unambiguously confirmed by the spectral
data. Its 1H NMR spectrum contains a triplet of
The tendency of amines as bases to induce the C P
bond cleavage evidently predetermines the complex
pattern of their reaction with imidoylphosphonates.
For example, the reaction with weakly basic 4-bromo-
aniline is fairly selective and yields amino amide XII
characterized by elemental analysis and spectral data
(Scheme 4).
2
doublets of the CHP proton ( 5.2 ppm, JHP 27.3,
3JHP 20.2 Hz). In the 13C NMR spectrum, the signal
of the CHP carbon atom is a doublet of doublets with
the typical direct coupling constant with phosphorus
(1JPC 164 Hz). Under the spin decoupling conditions,
the phosphoramidate and phosphonate phosphorus
atoms give a doublet and a triplet, respectively ( P 3.9
The reaction with more basic diethylamine leads
to an unexpected result. Diphosphorylated imine IVa
transforms into triphosphorylated amide XI and
monophosphorylared amidine XIII (Scheme 4). We
believe that transformation IVa XI follows
Scheme 5.
3
and 22.1 ppm, JPP 13 Hz), with 2:1 ratio of the
integral intensities.
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N-SULFONYL- AND N-PHOSPHORYLBENZIMIDOYLPHOSPHONATES
1213
Scheme 4.
p-BrC6H4NH2
O=P(OEt)2
P(OEt)2
Ph
N
H
p-BrC6H4NH
O
O=P(OEt)2
XII
P(OEt)2
Ph
N
O
O=P(OEt)2
IVa
O
P(OEt)2
Ph
N
Et2NH
NEt2
N
+
H
O
P(OEt)2
Ph
O=P(OEt)2
XI
XIII
Scheme 5.
O=P(OEt)2
Ph P(OEt)2
:B
Et2NH
N
XIII + (EtO)2P(O)H
IVa
fast
Et2N H
O
XIV
O=P(OEt)2
Et2NH
(EtO)2P(O)H
Ph
P(OEt)2
N
H
XI
IVa
(EtO)2P
O
O
Xa
The initially formed adduct XIV cannot be detected
spectroscopically, because diethylamine promotes fast
elimination of diethyl hydrogen phosphite from NH
acid XIV. Under the reaction conditions, phosphite
easily adds to the C=N bond of the starting imidoyl-
phosphonate IVa to give bisphosphonate Xa, which
undergoes 1,2-C N transfer of the phosphoryl group
catalyzed by diethylamine. It was shown in an in-
dependent experiment that diethylamine, indeed,
promotes the transformation Xa XI. Bisphospho-
nate Xa, amidine XIII ( 2.9 ppm), and diethyl
hydrogen phosphite were dPetected spectroscopically,
and phosphonate XI was identified by comparison
with a sample prepared following Scheme 4.
Scheme 6.
O=P(OEt)2
H2O
Ph
HO
P(OEt)2
N
H
IVa
O
B
O
(EtO)2P(O)NH2 +
Ph
P(OEt)2,
O
XV
XVI
H2O
XVI
PhCOOH + (EtO)2P(O)H.
philes were confirmed by elemental analysis and
spectral data. The transformation of imidoylphos-
phonates into aminoalkylphosphonates is accom-
panied by a significant downfield shift (10 15 ppm)
of the phosphonate phosphorus signal in the 31P NMR
spectra, which convenient for monitoring the reaction
progress. An important spectral feature of phosphoryl-
amino phosphonates RC6H4CX[NHP(O)(OR )2]P(O)
(OR)2 is that the coupling constants of the nonequiv-
alent phosphorus nuclei vary in a very wide range
(4 66 Hz depending on substituent X, Table 2).
Adducts of imidoylphosphonates IV with O-, S-,
and P-nucleophiles are fairly stable compounds slowly
decomposing during prolonged storage. On the con-
trary, addition of water to imine IVa causes decom-
position of the molecule (Scheme 6).
Low stability of adduct B is apparently due to easy
elimination of phosphoramidate XV and formation of
benzoylphosphonate XVI. Hydrolysis of XVI yields
benzoic acid and diethyl hydrogen phosphite, which
were identified by comparison with authentic samples.
The composition and structure of products formed
by the reactions of imidoylphosphonate with nucleo-
Note also the remote fluorine phosphorus coupling
in 4-fluorobenzylaminophosphonates Ia, Ic, IIc, IVb,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

1214
KOLOTILO et al.
Table 2. Chemical shifts ( P) and coupling constants of nonequivalent phosphorus atoms (3JPP) in amino phosphonates of
the general formula RC6H4CX[NHP(O)(OR )2]P(O)(OR)2
X
R
R
PN, ppm
PC, ppm
3JPP, Hz
MeO
H
H
H
H
H
4-F
3-F
4-Cl
H
4-Cl
4-Cl
4-Cl
H
Et
Et
Et
Et
Et
Ph
Ph
Ph
Et
Et
Ph
Ph
Et
5.3
5.3
4.6
5.7
7.4
8.6
8.4
8.1
4.8
4.4
4.4
2.0
3.5
17.1
18.4
17.3
17.9
22.7
16.4
16.0
14.8
18.5
17.2
10.1
6.8
66
51
50
49
49
42
41
40
22
16.5
35
27
7
SCH2COOH
4-ClC6H4S
SH
H
H
H
H
(EtO)2P(O)
(PhO)2P(O)
(EtO)2P(O)
(PhO)2P(O)
4-BrC6H4NH
18.0
3
and IXb (6JPF 1 6 Hz). Similar coupling also occurs
in imidoylphosphonates III, but in this case the con-
stant is smaller (for Ia and IIIa, JPF is 1.8 and
4.6 Hz, respectively). We found the similar effect pre-
viously for N-benzylidenamino-substituted fluoro-
ppm: 1.06 t (3H, CH3, JHH 6.6 Hz), 1.36 t (3H, CH3,
4JHH 6.6 Hz), 3.61 3.72 m (1H, CH2), 3.85 3.95 m
(1H, CH2), 4.22 4.28 m (2H, CH2), 4.80 d.d (1H,
CH, 2JHP 24, 3JHH 9.6 Hz), 6.77 t (2H, Ar, 3JHH 8 Hz),
6.97 br.s (1H, NH), 7.17 7.34 m (5H, Ar), 7.90 d (2H,
6
Ar, JHH 8 Hz). 19F NMR spectrum (CDCl3), F, ppm:
3
benzylphosphonates
4-FC6H4CH[P(O)R2]N=CHPh
114.17. 31P NMR spectrum (CDCl3), P, ppm:
20.1 d (2JPH 24 Hz). Found, %: C 50.44; H 5.12; P
7.84; S 8.21. C17H21FNO5PS. Calculated, %: C 50.87;
H 5.27; P 7.72; S 7.79.
[17]. This is a distinctive feature of N-substituted
-aminobenzylphosphonates. The trends we revealed
can be used in structural studies of related systems.
Our results show that N-sulfonyl- and N-phos-
phorylbenzimidoylphosphonates are promising for
Diethyl -(phenylsulfonylamino)-3-fluoroben-
preparing polyfunctional derivatives of
phosphonic acids.
-amino
zylphosphonate Ib. Yield 55%, mp 116 C. IR spec-
1
trum (KBr), , cm : 1050 (POC), 1180, 1350 (S=O),
1
1250 (P=O), 3150 (NH). H NMR spectrum (CDCl3),
EXPERIMENTAL
3
, ppm: 1.07 t (3H, CH3, JHH 6.6 Hz), 1.40 t (3H,
3
CH3, JHH 6.6 Hz), 3.59 3.67 m (1H, CH2), 3.85
The IR spectra were recorded on a UR-20 spec-
trometer. The 1H, 19F, 31P, and 13C NMR spectra were
taken on a Varian VXR-300 spectrometer, operating
frequences 299.95, 282.20, 121.42, and 75.428 MHz,
respectively. The chemical shifts are given relative to
internal TMS (1H, 13C), CFCl3 or PhF (19F), and ex-
ternal 85% phosphoric acid (31P). All reactions were
carried out in anhydrous solvents under argon.
3.96 m (1H, CH2), 4.28 4.38 m (2H, CH2), 4.85 d.d
2
3
3
(1H, CH, JPH 25, JHH 10 Hz), 6.78 t (1H, Ar, JHH
8 Hz), 6.97 7.15 m (3H, Ar, NH), 7.17 t (2H, Ar,
3JHH 8 Hz), 7.31 7.33 m (1H, Ar), 7.60 7.72 m (1H,
Ar), 7.60 7.72 m (3H, Ar). 19F NMR spectrum
(CDCl3), F, ppm: 113.55. 31P NMR spectrum
(CDCl3), P, ppm: 18.8 d (2JPH 25 Hz). Found, %: C
50.95; H 5.13; P 7.69; S 8.21. C17H21FNO5PS.
Calculated, %: C 50.87; H 5.27; P 7.72; S 7.99.
Compounds Ic, IIIc, IIId, and IXb were described
by us in a preliminary communication [8]. Sulfon-
amides Ia and Ib were prepared according to [8];
phosphoramidate IIa, according to [18]; and com-
pounds IIb IId, similarly to [19].
Diphenyl -(diethoxyphosphorylamino)-4-
chlorobenzylphosphonate IIb [19]. IR spectrum
1
(KBr), , cm : 960 (P O Ph), 1060 (POEt), 1230,
1255 (P=O), 3260 (NH). 31P NMR spectrum (C6H6),
3
P, ppm: 8.1 d (1P, PN, JPP 40 Hz), 14.8 d (1P, PC,
Diethyl -(phenylsulfonylamino)-4-fluoroben-
3JPP 40 Hz).
zylphosphonate Ia. Yield 58%, mp 148 C. IR spec-
1
trum, , cm : 1070 (POC), 1180, 1350 (S=O), 1250
Diphenyl -(diethoxyphosphorylamino)-4-
fluorobenzylphosphonate IIc. Yield 70%, mp 143
1
(P=O), 3160 (NH). H NMR spectrum (CDCl3),
,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

N-SULFONYL- AND N-PHOSPHORYLBENZIMIDOYLPHOSPHONATES
1215
1
1
145 C (acetone). H NMR spectrum (CDCl3), , ppm:
254 Hz), 176.8 d (C=N, JCP 198 Hz). 19F NMR spec-
trum (CDCl3), F, ppm: 106.18. 31P NMR spectrum
(CDCl3), P, ppm: 4.0. Found, %: C 51.34; H 4.91; P
7.65; S 7.98. C17H19FNO5P. Calculated, %: C 51.13;
H 4.80; P 7.76; S 8.03.
3
3
1.09 t (3H, CH3, JHH 7.2 Hz), 1.20 t (3H, CH3, JHH
7.2 Hz), 3.7 3.8 m (1H, CH2O), 3.90 4.0 m (3H,
2
CH2O), 4.4 br.s (1H, NH), 4.94 d.d.d (1H, CH, JHP
23.7, JHP 3JHH 11 Hz), 6.8 7.5 m (14H, Ar). 19F
3
NMR spectrum (benzene), F, ppm: 113.7. 31P {1H}
Diethyl N-(phenylsulfonyl)-3-fluorobenzimido-
ylphosphonate IIIb. Yield 87%. IR spectrum (in thin
film), , cm : 1070 (POC), 1180, 1350 (S=O), 1260
(P=O), 1610 (C=N). H NMR spectrum (CDCl3), ,
ppm: 1.20 m (6H, CH3), 4.03 4.22 m (4H, CH2),
7.22 t (1H, Ar, JHH 8 Hz), 7.45 7.62 m (6H, Ar),
7.91 d (2H, Ar, JHH 8 Hz). 13C NMR spectrum
3
NMR spectrum (CDCl3), P, ppm: 8.6 d (1P, PN, JPP
1
42 Hz), 16.4 d.d (1P, PC, 3JPP 42, 6JPF 4.6 Hz). Found,
1
%: P 12.47. C23H26FNO6P2. Calculated, %: P 12.55.
Diphenyl -(diethoxyphosphorylamino)-3-
3
fluorobenzylphosphonate IId. Yield 75%, mp 167
3
1
169 C (acetone). H NMR spectrum (CDCl3), , ppm:
3
(CDCl3), C, ppm: 16.0 d (CH3, JCP 6.6 Hz), 64.7 d
3
3
1.08 t (3H, CH3, JHH 7.3 Hz), 1.21 t (3H, CH3, JHH
(CH2, JCP 6 Hz), 115.2 d.d (C2, ArF, JCF 24, JCP
2
2
3
7.2 Hz), 3.7 m (1H, CH2O), 4.0 m (3H, CH2O), 4.3
3.7 Hz), 118.6 d (C4, ArF, JCF 19 Hz), 124.0 t (C6,
2
2
2
br.s (1H, NH), 4.95 d.d.d (1H, CH, JHP 23.8, JHP
3JHH 11 Hz), 6.84 m (2H, Ar), 7.0 7.5 m (12H, Ar).
19F NMR spectrum (C6H6), F, ppm: 112.5. 31P
{1H} NMR spectrum (CDCl3), P, ppm: 8.4 d (1P,
PN, JPP 41 Hz), 16.0 d.d (1P, PC, JPP 41, JPF
1.5 Hz). Found, %: P 12.57. C23H26FNO6P2. Cal-
culated, %: P 12.55.
ArF, JCP = JCP 6 Hz), 127.5 s (C2, C6, ArSO2),
3
4
128.9 s (C3, C5, ArSO2), 130.0 d (C5, ArF, JCF
3
7.8 Hz), 133.5 s (C4, ArSO2), 135.3 d.d (CC=N, JCP
2
3
1
3
3
3
26, JCF 9 Hz), 139.5 s (C SO2), 161.8 d (C F, JCF
1
249 Hz), 176.8 d (C=N, JCP 201 Hz). 19F NMR spec-
trum (CDCl3), F, ppm: 111.54. 31P NMR spectrum
(CDCl3), P, ppm: 3.6. Found, %: C 50.88; H 4.76;
P 7.83; S 8.12. C17H19FNO5PS. Calculated, %: C
51.13; H 4.80; P 7.76; S 8.03.
N-[(Diphenylphosphinoyl)(3-fluorophenyl)me-
thyl]benzenesulfonamide was prepared similarly to
[7]; yield 54%, mp 225 C. 19F NMR spectrum
(CDCl3), F, ppm: 113.75. 31P NMR spectrum
(C6H6), P, ppm: 33.3. Found, %: C 64.82; H 4.47.
C25H21FNO3PS. Calculated, %: C 64.51; H 4.55.
Diethyl N-(diethoxyphosphoryl)benzimidoyl-
phosphonate IVa. Yield 89%, bp 175 180 C
(0.05 mm Hg). IR spectrum (in thin film), , cm :
1
1
1240, 1250 (P=O), 1650 (C=N). H NMR spectrum
(CDCl3), , ppm: 0.78 m (6H, CH3), 0.92 m (6H,
CH3), 3.64 m (4H, OCH2), 3.85 m (4H, OCH2), 7.09
m (3H, Ph), 7.7 m (2H, Ph). 13C NMR spectrum
Imidoylphosphonates III and IV. To a solution
of 0.02 mol of chlorine in 60 ml of carbon tetrachlo-
ride, 0.044 mol of anhydrous pyridine was added
dropwise with stirring and cooling to 0 C. The result-
ing mixture was stirred for an additional 30 min and
then was gradually warmed to room temperature.
After that, 0.02 mol of appropriate amide were added
in portions. The reaction mixture was stirred for 8
10 h at room temperature, pyridine hydrochloride was
filtered off, and the filtrate was evaporated in a
vacuum.
3
(CDCl3), C, ppm: 15.1 d (CH3, JCP 6.4 Hz), 15.5 d
3
2
(CH3, JCP 5.8 Hz), 62.6 d (CH2, JCP 6.7 Hz), 63.3 d
2
(CH2, JCP 6.8 Hz), 127.2, 127.3 (C2, C3, Ph), 136.3
d.d (C1, Ph, 2JCP1 36 Hz, 3JCP 16 Hz), 130.6 s (C4, Ph),
181.0 d (C=N, JCP 195 Hz, JCP 6.5 Hz). 31P {1H}
2
NMR spectrum (CDCl3), P, ppm: 0.49 d (1P, PN,
3
3JPP 118 Hz), 3.81 d (1P, PC, JPP 118 Hz). Found,
%: P 16.29. C15H25HO6P2. Calculated, %: P 16.41.
Diethyl N-(phenylsulfonyl)-4-fluorobenzimido-
ylphosphonate IIIa. Yield 83%. IR spectrum (in thin
Diphenyl N-diethoxyphosphoryl-4-chlorobenz-
imidoylphosphonate IVb. Yield 80%. Viscous liquid.
1
film), , cm : 1070 (POC), 1180, 1350 (S=O), 1260
1
IR spectrum (in thin film), , cm : 1215 (POC),
1
1
(P=O), 1610 (C=N). H NMR spectrum (CDCl3), ,
1220, 1285 (P=O), 1645 (C=N). H NMR spectrum
3
4
ppm: 1.19 m (6H, CH3), 4.03 4.26 m (4H, CH2),
(CDCl3), , ppm: 1.09 d.t (6H, CH3, JHH 7.2, JPH
3
3
7.19 t (2H, Ar, JHH 8 Hz), 7.52 t (2H, Ar, JHH
0.9 Hz), 3.9 m (4H, OCH2), 7.1 7.4 m (10H, OPh),
3
3
3
8 Hz), 7.62 t (1H, Ar, JHH 8 Hz), 7.87 7.94 m (4H,
7.40 d (2H, Ar, JHH 8 Hz), 7.83 d (2H, Ar, JHH
Ar). 13C NMR spectrum (CDCl3), C, ppm: 15.8 d
8 Hz). 31P NMR spectrum (benzene), P, ppm: 5.2 d
(1P, PC, JPP 126 Hz), 0.5 d (1P, PN, JPP 126 Hz).
Found, %: P 12.09. C23H24ClNO6P2. Calculated, %:
P 12.20.
3
2
1
3
(CH3, JCP2 7 Hz), 64.5 d (CH2, JCP 7 Hz), 115.3 d
(C3, ArF, JCF 23 Hz), 127.2 s (C2, C6, ArSO2), 128.8
s (C3, C5, ArSO2), 129.6 d.d (CC=N, JCP 25, JCF
2
2
3 Hz), 131.0 d.d (C2, ArF, JCF 9, JCP 4 Hz), 133.3 s
3
3
Diphenyl N-diethoxyphosphoryl-4-fluorobenz-
imidoylphosphonate IVc. Yield 84%. Viscous oil.
(C4, ArSO2), 139.6 s (C SO2), 164.5 d (C F, JCF
1
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

1216
KOLOTILO et al.
19F NMR spectrum (CDCl3), F (PhF), ppm: 7.42. 31
P
(POC), 1180, 1350 (S=O), 1240 (P=O), 1720 (C=O),
NMR spectrum (CDCl3), P, ppm: 6.4 d (1P, PC,
3210 (NH). 1H NMR spectrum (CDCl3), , ppm:
3
2
3JPP 120 Hz), 1.4 d (1P, PN, JPP 120 Hz). Found,
1.21 m (6H, CH3), 2.87 d (1H, SCHA, JH H
A
B
2
15.6 Hz), 3.31 d (1H, SCHB, JH H 15.6 Hz), 4.01
4.19 m (4H, CH2), 6.32 d (1H, NH, JHP 8 Hz), 6.94 t
A
B
%: P 12.41. C23H24FNO6P2. Calculated, %: P 12.60.
3
Diphenyl N-diethoxyphosphoryl-3-fluorobenz-
imidoylphosphonate IVd. Yield 42%, viscous liquid.
3
3
(2H, Ar, JHH 8 Hz), 7.44 t (2H, Ar, JHH 8 Hz),
7.57 m (3H, Ar), 7.81 d (2H, Ar, JHH 8 Hz). 19F
3
13C NMR spectrum (CDCl3), C, ppm: 15.5 d (CH3,
NMR spectrum (CDCl3), F, ppm: 115.10. 31P NMR
spectrum (CDCl3), P, ppm: 16.0. Found, %: P 6.19;
S 13.11. C19H23FNO7PS2. Calculated, %: P 6.30;
S 13.05.
2
3JCP 7 Hz), 63.4 d (CH2, JCP 5.5 Hz), 114.9 d.d (C2,
2
3
2
ArF, JCF 24, JCP 4 Hz), 118.5 d (C4, ArF, JCF
21 Hz), 119.9 d (C2, PhO, JCP 5 Hz), 123.8 s (C6,
3
ArF), 125.2 (C4, PhO), 129.5 s (C3, PhO), 129.9 d
{[(Diethoxyphosphoryl)(phenylsulfonylamino)(3-
(C5, ArF, JCF 9 Hz), 137.5 d.d.d (CC=N, JCP 39,
3
2
fluorophenyl)methyl]thio}acetic acid VIIb. Yield
3JCP 15, JCF 7 Hz), 149.5 d (C1, PhO, JCP 8 Hz),
1
3
2
55%, mp 142 C. IR spectrum (KBr), , cm : 1060
1
1
161.6 d (C F, JCF 249 Hz), 177.1 d.d (C=N, JCP
(POC), 1180, 1350 (S=O), 1240 (P=O), 1720 (C=O),
206 Hz, JCP 8 Hz). 19F NMR spectrum (CDCl3),
2
3210 (NH). 1H NMR spectrum (CDCl3), , ppm:
F
(PhF), ppm: 2.05. 31P {1H} NMR spectrum (CDCl3),
2
1.25 m (6H, CH3), 3.18 d (1H, SCHA, JH H
A
B
3
2
16.8 Hz), 3.68 d (1H, SCHB, JH H 16.8 Hz), 3.95
4.17 m (4H, CH2), 7.04 t (1H, Ar, JHH 8 Hz), 7.31 t
A
B
P, ppm: 5.8 d (1P, PC, JPP 122 Hz), 0.6 d (1P,
PN, 3JPP 122 Hz). Found, %: P 12.69. C23H24FNO6P2.
3
3
Calculated, %: P 12.60.
(2H, Ar, JHH 8 Hz), 7.49 m (3H, Ar), 7.62 d (1H, Ar,
3JHH 8 Hz), 7.83 d (2H, Ar, JHH 8 Hz). 19F NMR
3
Diethyl -(phenylsulfonylamino)- -methoxy-4-
spectrum (CDCl3), F, ppm: 111.89. 31P NMR spec-
trum (CDCl3), P, ppm: 13.8. Found, %: P 6.23; S
13.17. C19H23FNO7PS2. Calculated, %: P 6.30; S
13.05.
fluorobenzylphosphonate Va.
A
solution of
0.5 mmol of imidoylphosphonate IIIa in 5 ml of ab-
solute methanol was kept at room temperature for
12 h. The solvent was removed in a vacuum, and the
residue was washed with petroleum ether. Yield
1
{[(Diethoxyphosphoryl)(diethoxyphosphoryl-
100%, mp 111 112 C. IR spectrum (KBr), , cm :
amino)(phenyl)methyl]thio}acetic acid VIIIa. Yield
1070 (POC), 1240 (P=O), 1180, 1350 (S=O), 3170
1
1
81%, mp 109 112 C (from hexane). H NMR spec-
(NH). H NMR spectrum (CDCl3), , ppm: 1.19 t
3
trum (CDCl3), , ppm: 1.04 t (3H, CH3, JHH 6.9 Hz),
3
3
(3H, CH3, JHH 7 Hz), 1.23 t (3H, CH3, JHH 7 Hz),
2
1.2 1.4 m (9H, CH3), 3.58 d (1H, SCHA, JH H
A
B
3.51 s (3H, CH3O), 3.89 4.11 m (4H, CH2), 6.38 d
2
12.9 Hz), 3.64 d (1H, SCHB, JH H 12.9 Hz), 3.9
A
B
3
3
(1H, NH, JHP 9.3 Hz), 6.84 t (2H, Ar, JHH 8 Hz),
7.37 7.63 m (7H, Ar). 19F NMR spectrum (CDCl3),
4.2 m (8H, OCH2), 4.5 br.s (1H, NH), 7.4 m (3H,
Ph), 7.7 d (2H, Ph). 31P NMR spectrum (CDCl3),
ppm: 5.3 d (PN, JPP 51 Hz), 18.4 d (PC, JPP 51 Hz).
Found, %: P 12.90; S 6.68. C17H27NO8P2S. Calcu-
lated, %: P 13.20; S 6.83.
,
F, ppm: 114.04. 31P NMR spectrum (CDCl3),
,
P
P
3
3
ppm: 14.9. Found, %: P 6.89; S 7.54. C18H23FNO6PS.
Calculated, %: P 7.18; S 7.43.
Diethyl -(diethoxyphosphoryl)amino- -(meth-
oxy)benzylphosphonate VI was prepared similarly.
Yield 96%, viscous oil. H NMR spectrum (CDCl3),
Diethyl -(diethoxyphosphoryl)amino- -(4-
1
chlorophenylthio)benzylphosphonate VIIIb. Yield
, ppm: 1.19 m (12H, CH3), 3.64 s (3H, CH3O),
3.96 m (8H, CH2), 7.32 m (3H, Ph), 7.73 m (2H, Ph).
31P NMR spectrum (benzene), P, ppm: 5.3 d (1P,
93%, viscous oil. 31P NMR spectrum (benzene),
ppm: 4.6 d (1P, PN, JPP 50 Hz), 17.3 d (1P, PC, JPP
50 Hz). Found, %: P 11.74; S 6.27. C21H30ClNO6P2S.
Calculated, %: P 11.86, S 6.14.
,
P
3
3
3
3
PN, JPP 66 Hz), 17.1 d (1P, PC, JPP 66 Hz). Found,
%: P 15.24. C16H29NO7P2. Calculated, %: P 15.13.
Diethyl -[(diethoxyphosphoryl)amino]- -
mercaptobenzylphosphonate VIIIc. Yield 83%,
viscous oil. 31P NMR spectrum (benzene), P, ppm:
5.7 d (1P, PN, JPP 49 Hz), 17.9 d (1P, PC, JPP
49 Hz). Found, %: P 14.64; S 7.48. C15H27NO6P2S.
Calculated, %: P 15.06; S 7.79.
Compounds VII. To a solution of 1 mmol of
appropriate imidoylphosphonate in 5 ml of diethyl
ether, 1 mmol of thioglycolic acid was added. After
standing for 12 h, the crystalline product was filtered
off.
3
3
{[(Diethoxyphosphoryl)(phenylsulfonylamino)(4-
Diethyl -diphenylphosphinoyl- -(phenylsul-
fonylamino)-4-fluorobenzylphosphonate IXa. Di-
phenylphosphine oxide, 0.12 g, was added to a solu-
fluorophenyl)methyl]thio}acetic acid VIIa. Yield
1
64%, mp 61 C. IR spectrum (KBr), , cm : 1060
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 8 2006

N-SULFONYL- AND N-PHOSPHORYLBENZIMIDOYLPHOSPHONATES
1217
tion of 0.29 g of imidoylphosphonate IIIa in 5 ml of
benzene. After 1 h, the solvent was evaporated, and
the residue was washed with petroleum ether. Yield
0.26 g (64%), mp 119 120 C. IR spectrum (KBr), ,
Diethyl -[bis(diethoxyphosphoryl)amino]ben-
zylphosphonate XI. Bisphosphonate Xa was applied
onto a thin nonfixed layer of Silicagel 60 (0.040
0.063 mm, Merck) on a glass plate and eluted with
ethyl acetate. After drying, the plate was developed
with iodine vapor for 15 min. The band containing
phosphonate XI was washed out with methanol, and
after evaporation of the solvent a clear viscous oil was
1
cm : 1060 (POC), 1180, 1340 (S=O), 1250 (P=O),
3220 (NH). 1H NMR spectrum (CDCl3), , ppm:
3
3
0.66 t (3H, CH3, JHH 7.2 Hz), 1.19 t (3H, CH3, JHH
7 Hz), 3.35 m (2H, CH2), 3.99 m (1H, CH2), 4.11 m
1
3
obtained, yield 72%. H NMR spectrum (CDCl3), ,
ppm: 1.2 1.3 m (18H, CH3), 4.0 4.3 m (12H, OCH2),
(1H, CH2), 6.68 t (2H, Ar, JHH 8 Hz), 7.09 d.d (1H,
3
3
NH, JHP 16.8 Hz, JHP 9.3 Hz), 7.26 m (2H, Ar),
2
3
7.36 7.54 m (8H, Ar), 7.81 8.00 m (7H, Ar). 13C
NMR spectrum (CDCl3), C, ppm: 15.5 d (CH3, JCP
7 Hz), 16.2 d (CH3, JCP 6 Hz), 62.1 d (CH2, JCP
5.2 d.t (1H, CHP, JHP 27.3, JHP 20.2 Hz), 7.3 m
(3H, Ph), 7.7 m (2H, Ph). 13C NMR spectrum (CDCl3,
ppm: 15.8 d (CH3, JCP 4 Hz), 15.9 d (CH3, JPC
3
3
3
3
2
3
3
4 Hz), 16.1 d (CH3, JCP 6.5 Hz), 16.2 d (CH3, JCP
2
1
6 Hz), 64.1 d (CH2, JCP 7 Hz), 68.4 d.d (CN, JCPOEt
1
2
5 Hz), 59.3 d (CP, JCP 164 Hz), 61.3 d (CH2, JCP
1
2
4
160, JCPPh 49 Hz), 114.0 d.d (C3, ArF, JCF 21, JCR
2
2
7.5 Hz), 63.3 d (CH2, JCP 4 Hz), 63.4 d (CH2, JCP
3.3 Hz), 127.2, 128.2, 128.3 (C2, C3, C4, PhSO2),
2
4 Hz), 64.1 d (CH2, JCP 7.5 Hz), 127.8 s (C3, Ph),
128.5 m (C1, ArF), 128.9 d (C1, PhP, JCP 63 Hz),
3
1
128.0 s (C4, Ph), 130.3 d (C2, Ph, JCP 5.8 Hz), 135.1
132.0, 133.3, 133.4 (C2, C3, C4, PhP), 132.2 d.d (C2,
ArF, J 11 and 3 Hz), 142.5 s (C SO2), 162.1 d (C F,
1JCF 251 Hz). 19F NMR spectrum (CDCl3), F, ppm:
(C1, Ph). 31P {1H} NMR spectrum (CDCl3), P, ppm:
3
3
3.9 d (2P, PN, JPP 13 Hz), 22.1 t (1P, PC, JPP
13 Hz). Found, %: P 17.91. C19H36NO9P3. Calculated,
%: P 18.02.
114.48. 31P {1H} NMR spectrum (CDCl3), P, ppm:
2
6
16.2 d.d (EtOP, JPP 9.8, JPF 1.1 Hz), 38.0 d.d (PhP,
2JPP 9.8 Hz, JPF 5.3 Hz). Found, %: P 10.24; S 5.09.
6
Diethyl -(4-bromophenylamino)- -[(diethoxy-
phosphorylamino]benzylphosphonate XII. Yield
C29H30FNO6P2S. Calculated, %: P 10.30; S 5.33.
60%, viscous oil. 31P {1H} NMR spectrum (CDCl3),
Bisphosphonates Xa Xc. To a solution of 1 mmol
of appropriate imidoylphosphonate IV in 5 ml of
benzene, an equimolar amount of the hydrophosphoryl
compound was added with stirring. The reaction mix-
ture was kept at room temperature for 5 (R = PhO) or
14 (R = EtO) days. The solvent was removed in a
vacuum.
3
P, ppm: 3.5 d (1P, PN, JPP 7 Hz), 18.0 d (1P, PC,
3JPP 7 Hz). Found, %: Br 15.07; P 11.25. C21H31Br
N2O6P2. Calculated, %: Br 14.55; P 11.28.
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Tetraethyl -[(diethoxyphosphoryl)amino]-
benzylidenephosphonate Xa. Yield 70%, viscous oil.
31P NMR spectrum (benzene), P, ppm: 4.8 t (1P, PN,
3
3JPP 22 Hz), 18.5 d (2P, PC, JPP 22 Hz). Found, %:
P 17.89. C19H36NO9P3. Calculated, %: P 18.02.
O,O-Diphenyl O ,O -diethyl -[(diethoxyphos-
phoryl)amino]-4-chlorobenzylidenebisphosphonate
Xb. Yield 75%, viscous oil. 31P {1H} NMR spectrum
3
(CDCl3), P, ppm: 4.4 d.d (1P, PN, JPNCPOPh 35,
3
3JPNCPOEt 16.5 Hz), 10.1 d.d (1P, PCOPh, 2JPP JPP
16.5 Hz), 17.2 d.d (1P, PCOEt, 2JPP 16.5, 3JPP 35 Hz).
Found, %: P 14.07. C27H35ClNO9P3. Calculated, %:
P 14.38.
Tetraphenyl -[(diethoxyphosphoryl)amino]-4-
chlorobenzylidenebisphosphonate Xb. Yield 80%,
viscous oil. 31P {1H} NMR spectrum (CDCl3),
ppm: 2.0 t (1P, PN, JPP 27 Hz), 6.8 d (2P, PC, JPP
27 Hz). Found, %: P 12.27. C35H35ClNO9P3. Cal-
culated, %: P 12.52.
,
P
3
3
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