N-(Arylsulfonyl)trihaloacetimidoyl Chlorides and Their Reactions with Phosphites

Article abstract of DOI:10.1002/ejoc.200300275

We have developed a convenient synthetic approach to highly reactive N-(arylsulfonyl)trichloro- and -trifluoroacetimidoyl chlorides 2 by reacting the corresponding N-acylsulfonamides with PCl₅. The interaction of the imidoyl chlorides with phos

Full text of DOI:10.1002/ejoc.200300275

FULL PAPER
N-(Arylsulfonyl)trihaloacetimidoyl Chlorides and Their Reactions with
Phosphites
[a]
[a]
[a]
Yuliya V. Rassukana, Petro P. Onys’ko,* Anatolii G. Grechukha, and
Anatolii D. Sinitsa[
a]
Keywords: Schiff bases / Sulfonamides / Phosphorylation / Umpolung / Synthetic design
We have developed a convenient synthetic approach to
highly reactive N-(arylsulfonyl)trichloro- and -trifluoroaceti- (phosphorylated) N-dihalovinylsulfonamides 8 and α-(aryl-
midoyl chlorides 2 by reacting the corresponding N-acylsul- sulfonylamino)trifluoroethylidenebis(phosphonates) 10.
fonamides with PCl . The interaction of the imidoyl chlorides
fonylamino-1-chlorotrifluoroethylphosphonate 5, C,N-bis-
A
5
rare example of an aza-Perkow reaction involving a trifluoro-
methyl group was discovered.
( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2003)
with phosphites proceeds through different pathways de-
pending on the substituents in the reagents, and leads to N-
arylsulfonyl-N-trichlorovinylphosphoramidates 4, 1-arylsul-
Introduction
ability of the sulfonyl group — they are unquestionably of
interest as potential building blocks in the synthesis of func-
Trihaloacetimidoyl chlorides are useful reagents for the tionalized nitrogen-containing compounds and as con-
synthesis of various acyclic and heterocyclic compounds venient models to study the specific effects that N-sulfonyl
having trihalomethyl groups.[1,2] The reagents having elec- substituents have on the reactivity of these molecules. The
tron-withdrawing acyl or phosphoryl groups (EWG) at the recently discovered N-to-C transfer of sulfonyl groups in
imine nitrogen atom are of particular preparative inter- reactions of trifluoroiminopyruvates with phosphites, which
est.[
1c,2]
The imidoyl chlorine atom in these compounds is leads to biologically important C-sulfonylated derivatives of
[
7]
easily substituted by another group (Y) and, in this way, a trifluoroalanine, illustrates the specificity of the chemistry
wide series of highly reactive imines X CϪC(Y)ϭNϪEWG of N-sulfonylated imines and the considerable preparative
3
(I) can be obtained. This strategy has already been used in opportunities they offer. The present work is dedicated to
the synthesis of imidoylphosphonates I (Y ϭ R PO; X ϭ the synthesis of the first representative examples of N-aryl-
2
F, Cl; EWG ϭ COR, R PO), which are starting compounds sulfonyltrihaloacetimidoyl chlorides and to their reactions
2
for the preparation of biologically active aminophosphonic with tervalent phosphorus nucleophiles.
[
1c,2Ϫ4]
acid derivatives.
The possibility of using this ap-
The following dominant or competing routes are known
proach to obtain compounds with fluorine-containing sub- for the reactions of phosphites with trihaloacetimidoyl
stituents and α-aminophosphonic acid residues in the same chlorides activated by EWGs other than sulfonamide ones:
molecule seems very attractive since fluorine substituents Arbuzov reactions involving the imidoyl chlorine
[
1c,2a,2b,3c,3d,4,8aϪ8c]
are widely used in the design of new drugs to improve their atom,
lipophilicity and to modify their pharmacological proper- pation of the trihalomethyl group,
aza-Perkow reactions with partici-
[
1c,3d,8a]
and cycload-
ties.[
1a,1b,5]
[2b,3c,9]
ditions leading to phosphoranes.
The relative import-
In contrast to N-acyl- and N-phosphoryl-substituted tri- ance of these pathways for the reactions of N-sulfonylated
haloacetimidoyl chlorides, their analogs having sulfonyl trihaloacetimidoyl chlorides has not been studied pre-
groups at the nitrogen atom are less well known. Only two viously.
representative examples of such compounds, i.e.,
[6]
CF C(Cl)ϭNSO X (X ϭ F, Cl) have been reported and
3
2
no information about N-sulfonyltrichloroacetimidoyl chlo- Results and Discussion
rides is available in the literature. Almost nothing is known
about the properties of the imidoyl chlorides, even
N-Arylsulfonyltrihaloacetimidoyl chlorides were pre-
though — because of the very strong electron-withdrawing pared by the sequence of reactions shown in Scheme 1.
Easily accessible N-arylsulfonyltrihaloacetamides 1 react
[
a]
Institute of Organic Chemistry, Ukrainian National Academy
of Sciences,
readily with phosphorus pentachloride upon heating in
benzene to give imidoyl chlorides 2 in almost quantitative
yields. The products are crystalline solids that are stable un-
5
Murmans’ka St., Kiev 02094, Ukraine
E-mail: onysko@rambler.ru
Eur. J. Org. Chem. 2003, 4181Ϫ4186
DOI: 10.1002/ejoc.200300275
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
4181

Y. V. Rassukana, P. P. Onys’ko, A. G. Grechukha, A. D. Sinitsa
FULL PAPER
Substituting the chlorine atoms of trichloroacetimidoyl
chloride 2a by fluorine atoms in the trifluoro analog 2c
changes the course of its reaction with triethyl phosphite
drastically. In the latter case, a C-phosphorylated product
is formed, rather than an N-phosphorylated one
(Scheme 2), but the imidoyl chlorine atom remains unreac-
tive. The primary steps in the reactions of 2a and 2c are
apparently similar and lead to the same intermediate A. In
view of similar electronic characteristics of CCl and CF
Scheme 1
3
3
[
12]
groups (σ ϭ 0.46 and 0.54, respectively), it is likely that
p
what distinguishes the transformations of A that follow is
determined by steric factors: the bulky trichloromethyl
group causes the neighboring phosphorus residue to mi-
grate rapidly to the nitrogen atom whereas, in the case of
the trifluoromethyl analog, the bipolar ion A is stabilized
through elimination of an ethylene molecule and pro-
tonation of the nitrogen atom. Compound 5 is formally an
addition product of diethyl phosphite and imidoyl chloride
der a dry atmosphere but are readily hydrolyzed in humid
air. Their spectroscopic data and elemental analyses con-
firm the structure proposed and show that the theoretically
possible chlorination of the sulfur atom — with the forma-
tion of isomeric compounds containing C(O)NϭS(Cl)
[
6b,10]
groups (cf.
) — did not take place in this case.
The presence of several reaction centers in compounds 2,
and the umpolung of some of them, results in a variety
of pathways and products in the reactions of the imidoyl
chlorides with nucleophilic phosphorus agents. Substituents
at the CϭN bond and at the phosphorus atom in the re-
agents also have a substantial effect on the pathway
2c, but, as established by independent experiments, the in-
teraction of these reagents under the above reaction con-
ditions does not produce phosphonate 5. The equilibrium
[
13]
formation of similar compounds having (EtO) P(O)
or
2
[
2b,11]
[
1c,2b,3,11]
CCl C(O)
substituents at the imino nitrogen atom,
taken
and, thus, the final results of these reactions
3
rather than sulfonyl groups, has been suggested previously,
but these compounds have not been isolated from solutions
because of their strong propensity to eliminate HCl or
are often difficult to predict a priori.
We have found that trichloroacetimidoyl chloride 2a re-
acts smoothly and regiospecifically with trialkyl phosphites
under mild conditions to form N-phosphorylated vinylsul-
fonamides 4 in high yields (Scheme 2).
(
EtO) P(O)H. Thus, phosphonate 5 is the first representa-
2
tive example of such a compound to be obtained in a pure
state and to be completely characterized by elemental
analysis and spectroscopic data.
α-Chloro-α-(tosylamino)trifluoroethylphosphonate 5 is a
white crystalline solid that is stable at room temperature
under an inert anhydrous atmosphere. Being an activated
halide, it reacts with triethyl phosphite even at room tem-
perature, but it forms a complex mixture of products.
Silyl phosphites often behave specifically and provide
good preparative results in reactions with electrophilic ag-
[
14]
ents. We have studied the interaction of imidoyl chlorides
also with diethyltrimethylsilyl phosphite (6). These reac-
2
tions follow a completely different course, involving two
equivalents of phosphite 6, and furnish C,N-bis(phosphory-
lated) products 8 (Scheme 3).
Scheme 2
Thus, the interaction follows the aza-Perkow reaction
[
1c]
route
involving a chlorine atom of the trichloromethyl
group, while the imidoyl chlorine atom remains unaltered.
Monitoring of the process by 31P NMR spectroscopy indi-
cates the absence of any C-phosphorylation products. The
reaction is most likely to begin with the nucleophilic attack
of the phosphite at the most electrophilic center: the im-
idoyl carbon atom. The subsequent CϪN migration of the
phosphorus group in the bipolar intermediate A, via the
cyclic phosphorane B, results in the formation of carbanion
3
1
C, which undergoes elimination of an alkyl chloride.
P
1
3
and C NMR spectra prove the structure of the vinylsul-
fonamides 4 unequivocally. The latter compounds do not
react with phosphites 3, as is expected for compounds hav-
[
1c,3]
ing such structures.
Scheme 3
4182
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Eur. J. Org. Chem. 2003, 4181Ϫ4186

N-(Arylsulfonyl)trihaloacetimidoyl Chlorides and Their Reactions with Phosphites
FULL PAPER
Therefore, in contrast to the reactions with trialkyl phos- portance to structural identification is the presence of the
phites presented in Scheme 2, silyl phosphite 6 reacts with signal in the 13C NMR spectrum that corresponds to the ϭ
trichloro- and trifluoroacetimidoyl chlorides by the same CP carbon atom (δ ϭ 126.4 and 89.3 ppm for 8a and 8c,
C
mechanism; the nature of the halogen substituents in sub- respectively) that is coupled to its directly bonded phos-
1
strates 2 has no effect on the direction of the reaction.
phorus atom ( J
ϭ 220Ϫ230 Hz) and also the presence
C,P
The first step of this reaction is most likely similar to that of signals of equal intensity from the phosphonate (δ ϭ
P
shown in Scheme 2. It results in the formation of a bipolar 9.3Ϫ9.8 ppm) and phosphate groups (δ between Ϫ3.0 and
P
ion D, but, because of the high migratory aptitude of the Ϫ4.4 ppm) in the 31P NMR spectra.
Me Si group, the former is stabilized by elimination of Me
Taking into account the high yields obtained for the
3
3-
SiCl from the intermediate E after the fast OϪN shift of preparation of compounds 8, the reactions represented in
the Me Si group (or immediately from betaine D) to give Scheme 3 can be considered as a convenient preparative ap-
3
imidoylphosphonates 7 rather than through the CϪN proach to the little-studied N-dichlorovinylamides and the
transfer of the phosphorus residue. These products are almost-unknown N-difluorovinylamides,[17] which may
more reactive than the starting imidoyl chlorides 2 because serve as useful starting substrates for further functionaliz-
[
2b,15]
[18,19]
of the strong activating effect of the phosphoryl group
ation.
and, for this reason, they react quickly with a second mol-
As is seen in Schemes 2 and 3, the reactions of imidoyl
ecule of phosphite 6 to form a bipolar ion F. The CϪN chlorides 2 with neutral esters of phosphorous acid occur
migration of the phosphorus group in the latter species mostly with the participation of the CX groups and are
3
(possibly via a cyclic phosphorane of type B) produces car- driven by the transformation of the latter into dihalomethy-
banion G, which undergoes elimination of the halide ion lene residues. This process is due to the formation of inter-
and is transformed into the stable bis(phosphorylated) mediate bipolar ions A or F, umpolung of the C and N
product 8; that is, an aza-Perkow reaction occurs in the se- reaction centers therein, and generation of carbanions C or
cond step. We note that only one example of an aza-Perkow G. It could be assumed that the intermediacy of the bipolar
transformation involving a CF group has been reported to ions is unlikely when acid phosphites are used as nucleo-
3
[
1c,16]
date.
The reaction shown in Scheme 3 occurs readily philic agents, and it could be expected that CX groups in
3
with both trifluoro- and trichloroacetimidoylphosphonates substrates 2 would remain unaltered. This concept would be
7
apparently because of the umpolung of the adjacent C particularly important for the preparation of functionalized
[
1a,1b,5]
and N reaction centers during the CϪN shift of the phos- derivatives having trifluoromethyl groups.
Indeed, we
phorus group.
have established that the reaction of trifluoroacetimidoyl
The intermediacy of imidoylphosphonates was confirmed chlorides 2b,c with diethyl phosphite takes a new course,
by additional experiments. Thus, when chloride 2a is re- namely the nucleophilic addition of two phosphite mol-
acted with one equivalent of phosphite 6 at Ϫ70 °C, a 1:1 ecules to the CϭN bond leading to the previously unknown
mixture of 7a (δP ϭ Ϫ3.7 ppm) and 8a (δ ϭ Ϫ4.4 and α-(sulfonylamino)trifluoroethylidenebis(phosphonates) 10
P
3
1
9.3 ppm) is formed, as evidenced by P NMR spectra. If (Scheme 5).
one equivalent of triethyl phosphite 3a or diethyl trimethyl-
silyl phosphite 6 is added to this reaction mixture, 7a is
completely transformed into 8a, whereas the addition of tri-
isopropyl phosphite 3b leads to the formation of vinylamide
9
(δ Ϫ6.0 and 9.5 ppm), which bears different phosphoryl
P
groups at its C and N atoms (Scheme 4).
Scheme 5
Whatever the ratio of the reagents is, the reaction does
not stop after the first monophosphorylation step. The
probable reason for this observation is that under the reac-
tion conditions (reflux in benzene) the initially formed ad-
Scheme 4
Thus, imidoylphosphonates 7 react with trialkyl phos- duct 5 readily eliminates HCl and transforms into imidoyl-
phites or diethyl trimethylsilyl phosphite by the same phosphonate 7. The latter species, being more reactive than
[
2b,15]
mechanism and the differences found in the reactions of the starting imidoyl chlorides,
reacts rapidly with a se-
imidoyl chlorides 2a؊c with these nucleophiles are deter- cond molecule of dialkyl phosphite to give the end product
mined by the different course of the first monophosphoryl- 10. Judging from the experimental findings, the rate-limit-
ation step.
ing step of the process is the addition of the phosphite to
The spectral and analytical data of compounds 8 are in the CϭN bond with the formation of adduct 5. The reac-
complete agreement with their structures. Of crucial im- tion path proposed for the transformation of 2 into 10 was
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Y. V. Rassukana, P. P. Onys’ko, A. G. Grechukha, A. D. Sinitsa
FULL PAPER
corroborated by the fact that phosphonate 5, obtained inde- of the CHal group, but not the imidoyl chlorine atom; (ii)
3
pendently by the process in Scheme 2, reacted with diethyl the substitution of the imidoyl chlorine atom with a phos-
phosphite to yield bis(phosphonate) 10b. Compounds 10 phorus-containing group, followed by transformations of
are stable and crystalline. NMR spectra clearly indicate that the resulting imidoylphosphonates in which the CHal3
the phosphoryl groups are equivalent and attached to the group takes part; (iii) the addition of a phosphite molecule
same carbon atom in the molecule.
to the CϭN bond and subsequent transformations of the
The simple preparative access to fluorinated bis(phos- primary adduct. The preferred reaction route depends on
phonates) of the type 10, as represented in Scheme 5, is of the nature of the phosphorus agent and the halogen in the
special importance when the wide spectrum of physiological CHal group. Despite the complexity and multistep charac-
3
activities exhibited by compounds containing a PϪCϪP ter of the process, these reactions are highly regioselective
triad is taken into consideration, particularly that of the and preparatively acceptable. The high and versatile reactiv-
aminomethylenebis(phosphonates).[
20]
ity of the imidoyl chlorides 2 renders them convenient re-
As can be seen in Scheme 3, the vicinal disposition of the agents for the synthesis of pharmacologically promising N-
nucleofuge and trimethylsilyl group in the intermediate E phosphorylated and C,N-bis(phosphorylated) halovinylsul-
promotes fast elimination of chlorotrimethylsilane and fonamides 4 and 8, α-sulfonamido-substituted ethylphos-
transformation of E into 7. In principle, the dialkoxyphos- phonate (5), and ethylidenebis(phosphonates) (10) bearing
phoryl group in bis(phosphonates) 10 can also act as a nu- trifluoromethyl groups. The umpolung of the C and N reac-
cleofuge. Hence, it follows that silylation of the nucleophilic tion centers mediated by the phosphorus reagents allows
nitrogen center in 10 and subsequent abstraction of the unusual transformations to be accomplished. The revealed
phosphoryl group may lead to the corresponding imidoyl- effects of the substituents in these reagents can aid the
phosphonate. We have found that bis(phosphonates) 10a,b choice of conditions for conducting syntheses of important
do undergo silylation at room temperature in the presence functionalized organophosphorus compounds having fluor-
of triethylamine, but the end products of these reactions ine-containing groups. The study of additional synthetic ap-
are the C,N-bis(phosphorylated) difluorovinylsulfonamides plications of imidoyl chlorides 2 in reactions with other nu-
8b,c, rather than the expected imidoylphosphonates 7. Such cleophiles is now in progress.
a surprising result can be readily explained by considering
Scheme 6.
Experimental Section
General Remarks: IR spectra were obtained using a UR-20 spectro-
1
13
19
31
photometer. H, C, F, and P NMR spectra were recorded with
a Varian VXRϪ300 spectrometer at 299.95, 75.43, 282.20, and
1
13
1
(
21.42 MHz, respectively, with internal TMS ( H, C), CFCl
3
1
9
31
3 4
F), and external 85% H PO ( P) as standards.
Scheme 6
N-(Trichloroacetyl)benzenesulfonamide (1a): A mixture of benzene-
sulfonamide (5 g, 31.8 mmol) and trichloroacetyl chloride (6.36 g,
35.0 mmol) was heated at 130 °C for 4 h. The precipitate that
formed was filtered off and washed with petroleum ether to give
It is likely that trimethylsilylamides 11 bearing two phos-
phoryl groups in the α-position are unstable[21] and readily
eliminate diethyl silyl phosphite 6 to form the highly electro-
philic imidoylphosphonates 7, which react rapidly with the
nucleophile 6 by the sequence of transformations depicted
in the second part of Scheme 3 to give the indicated sulfon-
1
a (9.6 g, 86%) as a white solid. M.p. 150Ϫ151 °C. IR (KBr): ν˜ ϭ
Ϫ1 1
1
180, 1375 (SϭO), 1790 (CϭO), 3270 (NH) cm
.
H NMR
3
(
CDCl
3
): δ ؍ 7.61 (t,
JHH ϭ 8 Hz, 2 H, m-CϪH, Ph), 7.72 (t,
3
3
JHH ϭ 8 Hz, 1 H, p-CϪH, Ph), 8.12 (d,
JHH ϭ 8 Hz, 2 H, o-
amides 8b,c. The latter compounds are identical to the com- CϪH, Ph), 8.95 (s, 1 H, NH) ppm. C H Cl NO S (302.56): calcd.
8
6
3
3
pounds obtained by reacting imidoyl chlorides 2b,c with C 31.76, H 2.00, Cl 35.15, N 4.63, S 10.60; found C 31.71, H 1.95,
two equivalents of phosphite 6 (Scheme 3).
Cl 35.38, N 4.72, S 10.86.
Considering Scheme 6 as a whole, we may infer that the
General Procedure for Preparation of N-(Trifluoroacetyl)arenesul-
fonamides 1b,c: A solution of benzenesulfonamide or p-toluenesul-
fonamide (38.2 mmol) and trifluoroacetic anhydride (45.8 mmol) in
benzene (25 mL) was heated under reflux for 6 h. The mixture was
cooled and the precipitate was filtered off and washed with benzene
and petroleum ether.
system Me SiCl ϩ Et N is formally a catalyst for the trans-
3
3
formation 10Ǟ8 via the CϪN shift of the phosphoryl
group.
Conclusion
N-(Trifluoroacetyl)benzenesulfonamide (1b): White solid, 9.5 g
(
98%). M.p. 135 °C. IR (CCl
4
): ν˜ ϭ 1180, 1370 (SϭO), 1780 (Cϭ
In summary, we have developed a simple synthetic ap-
proach to previously unknown N-(arylsulfonyl)trihaloaceti-
midoyl chlorides. The unusual reactivity of these com-
pounds clearly reveals itself in the interactions with phos-
Ϫ1
1
3
O), 3260 (NH) cm . H NMR (CDCl
2
(
3
): δ ϭ 7.63 (t, JHH ϭ 8 Hz,
3
H, m-CϪH, Ph), 7.76 (t, JHH ϭ 8 Hz, 1 H, p-CϪH, Ph), 8.13
d, JHH ϭ 8 Hz, 2 H, o-CϪH, Ph), 9.07 (s, 1 H, NH) ppm. 19
3
F
3 8 6 3 3
NMR (CDCl ): δ ϭ Ϫ75.30 ppm. C H F NO S (253.20): calcd. C
phites, which proceed through the following reaction path- 37.95, H 2.39, N 5.53, S 12.66; found C 37.81, H 2.37, N 5.49,
ways: (i) aza-Perkow conversion involving a halogen atom S 12.77.
4184
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N-(Arylsulfonyl)trihaloacetimidoyl Chlorides and Their Reactions with Phosphites
FULL PAPER
N-Trifluoroacetyl-p-toluenesulfonamide (1c): White solid, 10 g
34.10, H 3.58, Cl 25.16, P 7.33; found C 33.95, H 3.52, Cl 25.11,
P 7.38.
98%). M.p. 155 °C (ref.[ m.p. 155.5Ϫ156.5 °C). IR (KBr): ν˜ ϭ
22]
(
1
Ϫ1
1
160, 1375 (SϭO), 1790 (CϭO), 3270 (NH) cm
.
H NMR
Diisopropyl N-Phenylsulfonyl-N-(trichloroethenyl)phosphoramidate
3
(CDCl
3
): δ ϭ 2.49 (s, 3 H, CH
3
), 7.43 (d, JHH ϭ 8 Hz, 2 H, Ar),
.97 (d, JHH ϭ 8 Hz, 2 H, Ar), 9.11 (s, 1 H, NH) ppm. F NMR
(
1
1
4b): Colorless oil, 0.51 g (76%). IR (CCl
4
): ν˜ ϭ 1040 (POC), 1180,
380 (SϭO), 1280 (PϭO) cm . H NMR (CDCl ): δ ϭ 1.31 (m,
), 4.71Ϫ4.85 (m, 2 H, OCH), 7.47 (t, JHH ϭ 8 Hz, 2 H,
3
19
7
Ϫ1
1
3
(CDCl
3
): δ ϭ Ϫ76.30 ppm. C NO S (267.23): calcd. C 40.45,
9
H
8
F
3
3
3
2 H, CH
3
H 3.02, N 5.24, S 12.00; found C 40.62, H 3.13, N 5.16, S 11.86.
3
m-CϪH, Ph), 7.59 (t,
JHH ϭ 8 Hz, 1 H, p-CϪH, Ph), 8.01 (d,
3
31
General Procedure for Preparation of N-(Arylsulfonyl)trihaloacetim-
J
HH ϭ 8 Hz, 2 H, o-CϪH, Ph) ppm. P NMR (CDCl
19Cl NO PS (450.70): calcd. C 37.31, H 4.25, P
6.87, S 7.11; found C 37.18, H 4.08, P 6.93, S 6.98.
3
): δ ϭ
idoyl Chlorides 2a؊c: A mixture of the appropriate sulfonamide 1 Ϫ8.0 ppm. C14
and a small excess of PCl was heated under reflux in benzene
15Ϫ20 mL) for 6 h (for 2a) or 2 h (for 2b and 2c). The solvent was
H
3
5
5
(
Diethyl 1-Chloro-2,2,2-trifluoro-1-tosylaminoethylphosphonate (5):
Triethyl phosphite (0.37 g, 2.25 mmol) was added dropwise to a
stirred and cooled (Ϫ70 °C) solution of imidoyl chloride 2c (0.64 g,
2.25 mmol) in diethyl ether (10 mL). The precipitated product 5
evaporated under a reduced pressure and the residue was washed
with diethyl ether (2a, 2c) or distilled in vacuo (2b).
N-(Phenylsulfonyl)trichloroacetimidoyl Chloride (2a): White solid
prepared from 1a (7.0 g, 23.0 mmol) and PCl
in 96% yield (7.1 g). M.p. 100Ϫ101 °C. IR (CCl
5
(5.0 g, 24.0 mmol) was isolated by filtration (0.48 g, 45%). M.p. 90Ϫ91 °C. IR (CCl
4
):
Ϫ1
1
ν ϭ 1045 (POC), 1180, 1375 (SϭO), 1280 (PϭO) cm . H NMR
˜
): ν˜ ϭ 1175, 1365
4
Ϫ1
1
3
(CDCl ): δ ϭ 1.35 (t,
3
3
JHH
JHH ϭ 7 Hz, 3 H, CH CH ), 1.38 (t, ϭ
(
8
8
SϭO), 1640 (CϭN) cm . H NMR (CDCl
3
): δ ϭ 7.61 (t, JHH
ϭ
3
3
2
3
7 Hz, 3 H, CH CH ), 2.45 (s, 3 H, CH Ar), 4.28Ϫ4.35 (m, 4 H,
Hz, 2 H, m-CϪH, Ph), 7.71 (t, JHH ϭ 8 Hz, 1 H, p-CϪH, Ph),
3
2
3
3
13
OCH ), 6.33 (d,
3
JHP ϭ 11 Hz, 1 H, NH), 7.33 (d,
3
JHH ϭ 8 Hz, 2
):
3 2
CH
), 16.12 (d, 3JC,P ϭ 6.5 Hz,
.03 (d, JHH ϭ 8 Hz, 2 H, o-CϪH, Ph) ppm. C NMR (CDCl
3
):
2
3
13
δ ϭ 94.97 (s, CCl
s, p-C, Ph), 138.34 (s, ipso-C, Ph), 152.71 (s, CϭN) ppm.
Cl NO S (321.00): calcd. C 29.93, H 1.57, Cl 44.18, N 4.36,
3
), 127.59 (s, o-C, Ph), 129.25 (s, m-C, Ph), 134.34 H, Ar), 7.82 (d, JHH ϭ 8 Hz, 2 H, Ar) ppm. C NMR (CDCl
3
3
(
δ ϭ 16.03 (d, JC,P ϭ 6.5 Hz, CH
CH CH ), 21.58 (s, CH Ar), 66.70 (d, JC,P ϭ 8 Hz, CH
(d, JC,P ϭ 8 Hz, CH O), 75.02 (dq, JC,P ϭ 166.7, JC,F ϭ 36.7 Hz,
C,F ϭ 286 Hz, CF ), 128.29, 129.59, 136.71,
2
C
8
H
5
4
2
3
2
2
3
2
O), 67.62
1
2
S 9.99; found C 30.10, H 1.47, Cl 43.88, N 4.29, S 9.85.
2
1
CP), 120.96 (q,
J
3
N-(Phenylsulfonyl)trifluoroacetimidoyl Chloride (2b): White solid
19
31
1
(
44.85 (Ar) ppm. F NMR (CDCl
CDCl ): δ ϭ 8.66 ppm. C13 18ClF
3
): δ ϭ Ϫ68.54 ppm. P NMR
NO PS (423.77): calcd. C
prepared from 1b (4.0 g, 15.8 mmol) and PCl
5
(3.45 g, 16.6 mmol)
3
H
3
5
in 90% yield (3.9 g). B.p. 75Ϫ76 °C (0.07 Torr). M.p. 29Ϫ30 °C. IR
3
8
6.84, H 4.28, Cl 8.37, P 7.31, S 7.57; found C 36.89, H 4.25, Cl
.34, P 7.42, S 7.43.
Ϫ1
1
(
CCl
4
): ν˜ ϭ 1180, 1370 (SϭO), 1670 (CϭN) cm
): δ ϭ 7.62 (t, 3
HH ϭ 8 Hz, 2 H, m-CϪH, Ph), 7.74 (t,
HH ϭ 8 Hz, 1 H, p-CϪH, Ph), 8.02 (d, JHH ϭ 8 Hz, 2 H, o-
. H NMR
(
CDCl
3
J
3
3
General Procedure for Preparation of C,N-Bis(phosphorylated)
Compounds 8: Phosphite 6 (4.4 mmol) was added dropwise to a
stirred solution of the appropriate imidoyl chloride 2 (2.2 mmol) in
diethyl ether (10 mL) preliminarily cooled to Ϫ70 °C. The stirred
mixture was warmed to room temperature, the solvent was evapo-
rated in vacuo, and then the oily residue was washed with petro-
leum ether.
J
13
1
CϪH, Ph) ppm. C NMR (CDCl
CF ), 127.96 (s, o-C, Ph), 129.40 (s, m-C, Ph), 134.72 (s, p-C, Ph),
37.89 (s, ipso-C, Ph), 144.48 (q, JC,F ϭ 46 Hz, CϭN) ppm.
NMR (CDCl ): δ ϭ Ϫ72.60 ppm. C ClF NO S (271.63): calcd.
3
): δ ϭ 116.20 (q, JC,F ϭ 281 Hz,
3
2
19
1
F
3
8
H
5
3
2
C 35.37, H 1.86, Cl 13.05, S 11.80; found C 35.52, H 1.47, Cl 13.12,
S 11.68.
Diethyl N-(2,2-Dichloro-1-diethoxyphosphorylethenyl)-N-(phenylsul-
N-(Tosyl)trifluoroacetimidoyl Chloride (2c): A crystalline solid pre-
fonyl)phosphoramidate (8a): Colorless oil, 0.92 g (80%). IR (CCl
4
):
ν˜ ϭ 1020 (POC), 1180, 1380 (SϭO), 1280 (PϭO) cm . H NMR
(CDCl ): δ ϭ 1.27 (m, 12 H, CH CH ), 4.06Ϫ4.27 (m, 8 H, OCH ),
7.47 (t, JHH ϭ 8 Hz, 2 H, m-H, Ph), 7.58 (t, JHH ϭ 8 Hz, 1 H,
pared from 1c (5.5 g, 20.0 mmol) and PCl
5
(4.7 g, 22.0 mmol) in
): ν˜ ϭ
3
180, 1370 (SϭO), 1670 (CϭN) cm . H NMR (CDCl ): δ ϭ 2.4
Ϫ1
1
nearly quantitative yield (5.7 g). M.p. 41Ϫ42 °C. IR (CCl
4
Ϫ1
1
3
3
2
2
1
(
8
C
3
3
3
3
3
s, 3 H, CH ), 7.33 (d, JHH ϭ 8 Hz, 2 H, Ar), 7.81 (d, JHH ϭ
3
13
Hz, 2 H, Ar) ppm. 1 F NMR (CDCl
9
p-H, Ph), 7.99 (d, JHH ϭ 8 Hz, 2 H, o-H, Ph) ppm. C NMR
3
): δ ϭ Ϫ72.60 ppm.
7 3 2
H ClF NO S (285.67): calcd. C 37.84, H 2.47, Cl 12.41, N 4.90,
2
(
3 3
CDCl ): δ ϭ 14.35Ϫ16.53 (br, CH ), 63.15 (d, JC,P ϭ 6 Hz,
9
2
2
CH
CH
2
O), 63.23 (d,
J
C,P ϭ 6 Hz, CH
2
O), 64.76 (d, JC,P ϭ 6 Hz,
S 11.22; found C 37.81, H 2.55, Cl 12.43, N 4.85, S 11.31.
2
1
2
O), 64.96 (d, JC,P ϭ 6 Hz, CH O), 126.42 (d, JC,P ϭ 221 Hz,
2
General Procedure for Preparation of Dialkyl N-Phenylsulfonyl-N-
CP), 128.13 (s, o-Ph), 128.58 (s, m-Ph), 133.58 (s, p-Ph), 138.16 (s,
2
3
31
(
(
(
trichloroethenyl)phosphoramidates 4a,b: The appropriate phosphite
1.5 mmol) was added to a stirred solution of imidoyl chloride 2a NMR (CDCl ): δ ϭ Ϫ4.4 (m, 1 P, PN), 9.30 (m, 1 P, PC) ppm.
1.5 mmol) at 0 °C and then reacted for 2 h at room temperature.
ipso-Ph), 143.73 (dd, J
ϭ 34, J
C,P
ϭ 6 Hz, ϭCCl ) ppm.
P
C,P
2
3
16 25 2 8 2
C H Cl NO P S (524.29): calcd. C 36.65, H 4.81, Cl 13.52, P
The reaction mixture was concentrated in vacuo and the residue
was washed with petroleum ether.
11.82, S 6.12; found C 36.82, H 4.68, Cl 13.49, P 11.74, S 6.31.
Diethyl N-(1-Diethoxyphosphoryl-2,2-difluoroethenyl)-N-(phenylsul-
Diethyl N-Phenylsulfonyl-N-(trichloroethenyl)phosphoramidate (4a):
Colorless oil, 0.57 g (90%). IR (CCl
4
): ν˜ ϭ 1040 (POC), 1180, 1380
fonyl)phosphoramidate (8b): Colorless oil, 0.9 g (83%). IR (CCl
4
):
Ϫ1
1
ν˜ ϭ 1050 (POC), 1180, 1375 (SϭO), 1280 (PϭO) cm . H NMR
Ϫ1
1
3
3 3
(CDCl ): δ ϭ 1.32 (t, JHH ϭ 7 Hz, 6 H, CH ϭ
), 1.36 (t, 3JHH
3
(
SϭO), 1290 (PϭO) cm . H NMR (CDCl
3
): δ ϭ 1.32 (t, JHH
ϭ
3
3
7
4
1
Hz, 3 H, CH
H, OCH ), 7.56 (t, JHH ϭ 8 Hz, 2 H, Ph), 7.68 (t, JHH ϭ 8 Hz,
H, Ph), 8.09 (d, JHH ϭ 8 Hz, 2 H, Ph) ppm. 13C NMR (CDCl
3
), 1.36 (t, JHH ϭ 7 Hz, 3 H, CH ), 4.13Ϫ4.30 (m, 7 Hz, 6 H, CH ), 4.2 (m, 8 H, OCH ), 7.54 (t, JHH ϭ 8 Hz, 2 H,
3
3
2
3
3
3
3
2
m-H, Ph), 7.66 (t, JHH ϭ 8 Hz, 1 H, p-H, Ph), 8.08 (d, JHH ϭ
3
19
3
3
3
): 8 Hz, 2 H, o-H, Ph) ppm. F NMR (CDCl ): δ ϭ Ϫ69.92 (ddd,
),
3
3
2
3
4
2
δ ϭ 15.77 (d, JC,P ϭ 6.5 Hz, CH
3
), 15.80 (d, JC,P ϭ 6.5 Hz, CH
O), 65.42 (d, 2
C,P ϭ 6 Hz, CH
), 128.74 (s, o-C, Ph), 128.80 (s, ϭCCl), 128.94 (s, Ϫ3.0 (1 P, PN), 9.76 (1 P, PC) ppm. C16
J
FF ϭ 17.2, JFP ϭ 17.2, JFP ϭ 8 Hz, 1 F), Ϫ64.68 (ddd, JFF
ϭ
5.15 (d, 2
24.11 (s, CCl
J
C,P ϭ 6 Hz, CH
J
O),
17.2, JFP ϭ 21.5, 4JFP ϭ 6 Hz, 1 F) ppm. P NMR (CDCl
3
31
): δ ϭ
6
1
2
2
3
2
H
25
F
2
NO
8
P
2
S (491.38):
31
m-C, Ph), 134.26 (s, p-C, Ph), 138.31 (s, ipso-C, Ph) ppm. P NMR
calcd. C 39.11, H 5.13, N 2.85, P 12.61, S 6.53; found C 38.96, H
5.24, N 2.76, P 12.74, S 6.49.
(CDCl
3
): δ ϭ Ϫ5.1 ppm. C12
H15Cl
3
NO
5
PS (422.65): calcd. C
Eur. J. Org. Chem. 2003, 4181Ϫ4186
www.eurjoc.org
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
4185

Y. V. Rassukana, P. P. Onys’ko, A. G. Grechukha, A. D. Sinitsa
prigorina, P. P. Onys’ko, Zh. Obshch. Khim. 2002, 72,
FULL PAPER
Diethyl N-(1-Diethoxyphosphoryl-2,2-difluoroethenyl)-N-tosylphos-
1798Ϫ1801.
phoramidate (8c): Colorless oil, 0.97 g (87%). IR (CCl
4
): ν˜ ϭ 1020
[
3] [3a]
POC), 1180, 1380 (SϭO), 1280 (PϭO) cm . 1H NMR (CDCl
Ϫ1
P. P. Onys ’ko, A. D. Sinitsa, N. V. Kolotylo, E. A. Suvalova,
(
3
):
δ ϭ 1.14 (m, 12 H, CH CH ), 2.22 (s, 3 H, CH Ar), 3.95Ϫ4.21 (m,
), 7.11 (d, JHH ϭ 8 Hz, 2 H, Ar), 7.72 (d, JHH ϭ 8 Hz,
[
3b]
Phosphorus, Sulfur, Silicon Relat. Elem. 1999, 147, 381.
P. Onys ’ko, A. A. Sinitsa, N. V. Kolotylo, Main Group Chem.
P.
3
2
3
3
3
8
2
CH
H, OCH
H, Ar) ppm. 13C NMR (CDCl
CH C,P ϭ 6 Hz, CH
), 15.90 (d, 3
Hz, CH CH ), 16.10 (d,
Ar), 63.25 (d, JC,P ϭ 6 Hz, CH
O), 64.71 (d, 2
C,P ϭ 6 Hz, CH
2
[3c]
News 1997, 5, 27Ϫ28.
P. P. Onys ’ko, Russ. J. Gen. Chem.
): δ ϭ 15.80 (d, 3
CH
C,P ϭ 6 Hz, CH
O), 63.33 (d, JC,P ϭ 6 Hz,
J
C,P ϭ 6 Hz,
3
[3d]
1999, 69, 153Ϫ154.
V. I. Boiko, A. A. Sinitsa, P. P. Onys’ko,
3
3
2
J
3
2
), 16.01 (d,
CH
J
C,P
ϭ
Russ. J. Gen. Chem. 1999, 69, 1879Ϫ1882.
[3e]
P. P. Ony s ’ko, A.
3
6
3
2
J
3
2
), 21.54 (s,
A. Sinitsa, Yu. V. Rassukana, Ya. A. Sizonenko, A. D. Sinitsa,
Abstr., Int. Conf. on Phosphorus Chem. Sendai, 2001, PA108.
S. N. Osipov, O. I. Artyushin, A. F. Kolomiets, Mendeleev
Commun. 2000, 192Ϫ193.
5]
2
2
CH
CH
CH
3
2
2
2
2
[4]
J
2
O), 65.23 (d,
J
C,P ϭ 6 Hz,
O), 89.29 (ddd, JC,P ϭ 230, JC,F ϭ 41.5, JC,F ϭ 7.7 Hz, CP),
), 144.96 (s, CCH ),
1
2
2
[
Organic Compounds in Medicinal Chemistry and Biomedicinal
Applications, (Eds: R. Filler, Y. Kobayashi, L. M. Yagupolskii),
Elsevier, Amsterdam, 1993. B. Xu, S. Zhu, Heteroatom Chem.
128.89 (s, Ar), 129.15 (s, Ar), 135.29 (s, CSO
2
3
1
1
2
3
162.41 (dddd, JC,F ϭ 315, JC,F ϭ 305, JC,P ϭ 35, JC,P ϭ 4 Hz, ϭ
CF
2
) ppm. 19F NMR (CDCl
FP ϭ 17.2, JFP ϭ 8 Hz, 1 F), Ϫ64.20 (ddd, JFF ϭ 17.2, JFP
3
): δ ϭ Ϫ69.40 (ddd, 2JFF ϭ 17.2,
1997, 8, 309Ϫ315.
3
4
2
3
J
ϭ
[6] [6a]
H. W. Roesky, H. H. Giere, Chem. Ber. 1969, 102,
1.2, 4JFP ϭ 5 Hz, 1 F) ppm. P NMR (CDCl
31
): δ ϭ Ϫ3.0 (dd,
2
J
1
3
[6b]
3707Ϫ3712.
H. W. Roesky, H. H. Giere, D. P. Babb, Inorg.
4
PF ϭ 8, 4JPF ϭ 5 Hz, 1 P, PN), 9.85 (dd, 3JPF ϭ 21.2, JPF
7.2 Hz, 1 P, PC) ppm. C17 NO S (505.41): calcd. C 40.40,
H 5.38, P 12.26, S 6.34; found C 40.58, H 5.33, P 12.32, S 6.31.
3
ϭ
Chem. 1970, 9, 1076Ϫ1079.
[
[
7]
H
27
F
2
8
P
2
P. P. Onys ’ko, O. A. Suvalova, Yu. V. Rassukana, T. I. Chu-
dakova, A. D. Sinitsa, Tetrahedron Lett. 2003, 44, 1855Ϫ1857.
8] [8a]
A. D. Sinitsa, K. S. Krishtal, V. I. Kal’chenko, Zh. Obshch.
Khim. 1980, 50, 465Ϫ466. [ A. D. Sinitsa, T. V. Kolodka, A.
K. Shurubura, Zh. Obshch. Khim. 1987, 57, 475Ϫ477.
8b]
General Procedure for Preparation of Bis(phosphonates) 10a,b: A
solution of imidoyl chloride 2b,c (2.2 mmol) and diethyl phosphite
[
8c]
W.
Huang, Y. Zhang, C. Yuan, Phosphorus, Sulfur, Silicon Relat.
Elem. 1995, 107, 21Ϫ26. C. Yuan, Y. Zhang, Heteroatom
Chem. 2002, 13, 22Ϫ26.
P. P. Onys ’ko, T. V. Kolodka, A. A. Kudryavtsev, A. D. Sinitsa,
Zh. Obshch. Khim. 1993, 63, 1562Ϫ1566. P. P. Onys’ko, T. V.
Kolodka, N. V. Kolotylo, A. A. Kudryavtsev, A. D. Sinitsa, Zh.
Obshch. Khim. 1994, 64, 396Ϫ402.
N. V. Kolotilo, A. A. Sinitsa, P. P. Onys’ko, Russ. J. Gen. Chem.
1997, 67, 154Ϫ155.
Yu. V. Rassukana, K. O. Davydova, P. P. Onys’ko, A. D. Sin-
itsa, J. Fluor. Chem. 2002, 117, 107Ϫ113.
(4.4 mmol) in benzene (10 mL) was heated under reflux for 1 h,
cooled, and then concentrated in vacuo. The residue was washed
with petroleum ether.
[9]
Tetraethyl
2,2,2-Trifluoro-1-(phenylsulfonylamino)ethylidenebis-
(phosphonate) (10a): White powder, 0.7 g (63%). M.p. 82 °C. IR
Ϫ1
1
[10]
(
CCl
4
): ν˜ ϭ 1050 (POC), 1180, 1360 (SϭO), 1275 (PϭO) cm . H
): δ ϭ 1.31 (t, 3
HH ϭ 7 Hz, 6 H, CH ), 1.34 (t,
3 2
HH ϭ 7 Hz, 6 H, CH ), 4.21Ϫ4.32 (m, 8 H, OCH ), 5.69 (t,
NMR (CDCl
3
J
3
[
11]
3
J
3JHP ϭ 14 Hz, 1 H, NH), 7.49 (t, JHH ϭ 8 Hz, 2 H, m-H, Ph),
7
3
[
[
12]
13]
C. Hansch, A. Leo, R. W. Taft, Chem. Rev. 1991, 91, 165Ϫ195.
N. V. Kolotilo, A. D. Sinitsa, P. P. Onys’ko, Zh. Obshch. Khim.
.53 (t, 3JHH ϭ 8 Hz, 1 H, p-H, Ph), 8.04 (d, JHH ϭ 8 Hz, 2 H, o-
3
19
3
H, Ph) ppm. F NMR (CDCl
3
): δ ϭ Ϫ64.31 (t, JFP ϭ 8 Hz) ppm.
): δ ϭ 11.76 ppm. C16 NO S (511.38):
calcd. C 37.58; H 5.12; P 12.11; S 6.27; found C 37.35; H 5.23; P
1.98; S 6.34.
1994, 64, 1304Ϫ1305.
[14]
3
1
P NMR (CDCl
3
H
26
F
3
8
P
2
K. Afarinkia, C. W. Rees, J. I. G. Cadogan, Tetrahedron 1990,
46, 7175Ϫ7196.
P. P. Onys ’ko, T. V. Kolodka, A. D. Sinitsa, Zh. Obshch. Khim.
[
[
[
15]
16]
17]
1
1
995, 65, 948Ϫ954.
N. V. Kolotilo, A. A. Sinitsa, P. P. Onys’ko, Zh. Obshch. Khim.
995, 65, 1221Ϫ1222.
Tetraethyl 2,2,2-Trifluoro-1-(tosylamino)ethylidenebis(phosphonate)
1
(
(
10b): White powder, 0.65 g (58%). M.p. 83 °C. IR (CCl
4
): ν˜ ϭ 1050
POC), 1180, 1360 (SϭO), 1280 (PϭO) cm . H NMR (CDCl ):
), 1.34 (t, JHH ϭ 7 Hz, 6
Ar), 4.18Ϫ4.33 (m, 8 H, OCH ),
Ϫ1
1
Only one example of unphosphorylated difluorovinylsulfonam-
ides has been reported so far. See: Yu. V. Zeifman, Izv. Akad.
Nauk SSSR, Ser. Khim. 1990, 202Ϫ205.
3
3
3
3 2
δ ϭ 1.32 (t, JHH ϭ 7 Hz, 6 H, CH CH
H, CH
3
3
CH
2
), 2.41 (s, 3 H, CH
3
2
[18]
[19]
B. S. Drach, V. S. Brovarets, O. S. Smolii, Syntheses of Nitro-
gen-Containing Heterocyclic Compounds on the Basis of Ami-
doalkylating Agents (in Russian), Naukova Dumka, Kiev, 1992.
A. D. Sinitsa, T. V. Kim, E. I. Kiseleva, P. P. Onys’ko, Phos-
phorus, Sulfur, Silicon Relat. Elem. 2002, 177, 2055.
3
5
.66 (t, JHP ϭ 14 Hz, 1 H, NH), 7.30 (d, JHH ϭ 8 Hz, 2 H, Ar),
.91 (d, 3
JHH ϭ 8 Hz, 2 H, Ar) ppm. F NMR (CDCl
3
19
): δ ϭ
): δ ϭ 11.07 ppm.
S (525.41): calcd. C 38.86, H 5.37, P 11.79, S 6.10;
found C 39.00, H 5.20, P 11.59, S 6.37.
7
Ϫ64.23 (t, JFP ϭ 8 Hz) ppm. 31P NMR (CDCl
3
3
17 28 3 8 2
C H F NO P
[
20]
G. Russel, Phosphorus, Sulfur, Silicon Relat. Elem. 1999,
144Ϫ146, 793Ϫ820. F. H. Ebetino, Phosphorus, Sulfur, Silicon
Relat. Elem. 1999, 144Ϫ146, 9Ϫ12. L. Widler, K. A. Jaeggi, J.
R. Green, Phosphorus, Sulfur, Silicon Relat. Elem. 1999,
144Ϫ146, 5Ϫ8. J. Mönkkönen, N. Makkonen, M. J. Rogers, J.
C. Frith, S. Auriola, Phosphorus, Sulfur, Silicon Relat. Elem.
1999, 144Ϫ146, 321Ϫ324.
21]
[
[
1] [1a]
K. Uneyama, J. Fluor. Chem. 1999, 97, 11Ϫ25. [1b] K. Ta-
mura, H. Mizukami, K. Maeda, H. Watanabe, K. Uneyama,
J. Org. Chem. 1993, 58, 32Ϫ35. [ O. A. Sinitsa, N. V. Kolotilo,
P. P. O ny s ’ko, Ukr. Khim. Zh. 1998, 64, 47Ϫ66 [Ukr. Chem. J.
1c]
[
A. D. Sinitsa, N. A. Parkhomenko, L. N. Markovskii, Zh.
Obshch. Khim. 1983, 53, 354Ϫ359.
[22]
1
998, 64, 43Ϫ61 (Engl. Transl.)].
2] [2a]
P. P. O ny s ’ko, A. A. Sinitsa, V. V. Pirozhenko, A. N. Cher-
V. A. Nikolaev, P. Yu. Utkin, I. K. Korobitsyna, Zh. Org. Khim.
1989, 25, 1176Ϫ1179.
[2b]
nega, Heteroatom Chem. 2002, 13, 22Ϫ26.
kana, Ya. A. Sizonenko, A. A. Sinitsa, V. I. Boiko, A. A. Podo-
Yu. V. Rassu-
Received May 8, 2003
4186
 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
Eur. J. Org. Chem. 2003, 4181Ϫ4186