Higher 1,3,2-diazaphosphacyclanes: V. Synthesis, structure, and chemical features of 4,5 ;7,8-dibenzo-1,3,2-diazaphosphocanes

Article abstract of DOI:10.1023/A:1015409231657

A procedure was developed for preparing 4,5; 7,8-dibenzo-1,3,2-diazaphosphocanes containing trivalent and pentavalent phosphorus atoms. The structure of the compounds was determined by NMR spectroscopy and single crystal X-ray diffraction. The conformational transitions of the diazaphosphocanes in solution were analyzed. First data were obtained on transformations of the obtained eight-membered heterocycles.

Full text of DOI:10.1023/A:1015409231657

Russian Journal of General Chemistry, Vol. 72, No. 2, 2002, pp. 193 206. Translated from Zhurnal Obshchei Khimii, Vol. 72, No. 2, 2002,
pp. 212 225.
Original Russian Text Copyright
2002 by Nifant’ev, Zavalishina, Orzhekovskaya, Selezneva, Vasyanina, Vorontsov, Stash, Bel’skii.
Higher 1,3,2-Diazaphosphacyclanes:
V.1 Synthesis, Structure, and Chemical Features
of 4,5;7,8-Dibenzo-1,3,2-diazaphosphocanes
E. E. Nifant’ev, A. I. Zavalishina, E. I. Orzhekovskaya, N. M. Selezneva, L. K. Vasyanina,
E. V. Vorontsov, A. I. Stash, and V. K. Bel’skii
Moscow State Pedagogical University, Moscow, Russia
Received July 21, 2000
Abstract A procedure was developed for preparing 4,5;7,8-dibenzo-1,3,2-diazaphosphocanes containing
trivalent and pentavalent phosphorus atoms. The structure of the compounds was determined by NMR spec-
troscopy and single crystal X-ray diffraction. The conformational transitions of the diazaphosphocanes in
solution were analyzed. First data were obtained on transformations of the obtained eight-membered hetero-
cycles.
1,3,2-Diazaphosphacyclanes with five- [2], six-
and steric structure of the obtained compounds by
[3 5], and seven-membered [1] rings have been sub- X-ray diffraction and independent synthesis.
ject to comprehensive synthetic and structural studies,
The aim of this work is to develop of a general
as well as to applied research [6]. At the same time,
route to 1,3,2-diazaphosphocanes containing trivalent
much less attention was given to the corresponding
phosphorus atoms. If necessary, these compounds can
eight-membered cyclic systems. Data are available
be converted by oxidative methods to various penta-
[7 10] only on the reaction of N,N-dimethyl-p-tolu-
valent phosphorus derivatives.
idine with phosphorus oxychloride and thiochloride,
affording 4,5;7,8-dibenzo-1,3,2-diazaphosphocanes in
moderate yields. These compounds contain in their
structure the phosphoryl and thiophosphoryl groups.
The reaction in question is unusual. Shaw et al. [7 10]
discussed its mechanism and elucidated the chemical
2,2 -Methylenebis-p-toluidine I and N,N -diisopro-
pyl-2,2 -methylenebis-p-toluidine II were chosen as
starting compounds. First we studied the reaction of
diamine I with phenyl- and p-cresyl phosphorodi-
chloridites in the presence of triethylamine.
Me
Me
Me
H
H
NH2
NH2
N
N
N
N
S
2NEt3
S
CH2
+ Cl2POAr
CH2
P OAr
H
CH2
P
OAr
H
Me
Me
Me
I
III, IV
V, VI
Ar = Ph (III, V), C6H4CH3 (IV, VI).
The reaction proceeds easily. The 31P NMR spec-
trum of the reaction mixture contains only one singlet
ly, we failed to isolate these compounds pure. They
polymerize during vacuum distillation and are hydro-
lyzed during chromatographic purification. Therefore,
for determining the structure, these compounds were
isolated and characterized as the corresponding thio-
phosphates V and VI.
with
107.61 or 107.88 ppm, belonging to phos-
phorodPiamidites III and IV, respectively. Unfortunate-
1
For communication IV, see [1].
1070-3632/02/7202-0193$27.00 2002 MAIK Nauka/Interperiodica

194
NIFANT’EV et al.
The reaction of diamine I with aliphatic acid chlo-
decoupling, the latter signal is a doublet with JPH
614 Hz. Such a spectrum suggests the presence of
two tautomers: phosphite and iminohydrophosphoryl
species.
rides is more complex. The 31P NMR spectrum of
the reaction products contains two signals with P 113
and 6 ppm. In the spectrum recorded without proton
Me
Me
Me
H
H
N
N
N
N
N
H
S
I + Cl2POAlk 2NEt
S
3
CH2
P OAlk
H
CH2
P
CH2
P
OAlk
OAlk
N
H
H
Me
Me
Me
VII, VIII
Alk = Et (VII), n-Bu (VIII).
Treatment of the reaction mixture with sulfur yields
In the spectra of the reaction mixtures we detected
the signals related to the target products. Because of
their lability, we failed to isolate these compounds
pure, but crude products can be used in synthetic prac-
tice without special purification. For example, we
showed that 1,3-diisopropyl-1,3,2-diazaphosphocanes
easily take up sulfur and oxygen with the formation
of stable compounds.
thiophosphates VII and VIII, with disappearance of
the signals with
113 and 6 ppm. This fact confirms
our suggestion abPout the prototropism of the primary
phosphorylation products.
The different results of cyclophosphorylation with
aliphatic and aromatic phosphorochloridites are ev-
idently due to different electron-accepting powers of
alkoxy and aroxy groups.
Me
Pr-i
The electron-accepting power of aroxy groups in
phosphocanes III and IV is manifested in the ex-
tremely easy hydrolysis of these compounds, yielding
hydrophosphoryl compounds IX.
N
Y
X
S
X XIV
CH2
P
[O]
N
Pr-i
Me
Me
XV XX
H
N
O
Y = S, X = Cl (XV), OMe (XVI), OEt (XVII), OPh
(XVIII), NEt2 (XIX); Y = O, X = OEt (XX).
H2O
III, IV
CH2
P
H
N
O-Ethyl phosphoramidothioate XVII, when treated
with excess methyl iodide, is converted to S-methyl
phosphoramidothioate XXI.
H
Me
IX
Note that the hydrolytic cleavage of the phosphite
bond with the preservation of the phosphoroamidite
group under the same conditions is an unusual fact.
Me
Pr-i
N
O
CH3I
Further experiments on synthesis of 1,3,2-diaza-
phosphocanes were performed with N,N -diisopropyl-
2,2 -methylenebis-p-toluidine II. It was shown that
diamine II is readily phosphorylated with phospho-
rus trichloride, alkyl and aryl phosphorodichloridites,
and diethylphosphorodichloridous amide.
XVII
CH2
P
S Me
N
Pr-i
Me
XXI
Diamido ester XII was subjected to alkylation with
excess methyl iodide (Arbuzov reaction).
Me
Pr-i
Me
N
Cl
Pr-i
2NEt3
II +
P X
CH2
P X
N
O
CH3I
Cl
N
XII
CH2
P
Me
Pr-i
N
Me
Pr-i
X XIV
Me
X = Cl (X), OMe (XI), OEt (XII), OPh (XIII), NEt2 (XIV).
XXII
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
195
Phosphorochloridite X was studied in nucleophilic
substitutions of chlorine.
dihydro-4,5;7,8-dibenzo-11,11 -dimethyl-1,3,2-diaza-
phosphocane 2-sulfides VI shows that the protons of
the methylene ring do not preferably occupy the axial
or equatorial position. It is important that the down-
Me
Me
Pr-i
Pr-i
5
field signal has the coupling constant JPH 2.1 Hz.
N
N
N
N
O
H2O
HNR2
This fact suggests that in solution 1,3-dihydro-1,3,2-
diazaphosphocane 2-sulfides V and VI behave as
a two-component system containing the axial and
CH2
P
X
CH2
P
NR2
H
Pr-i
Pr-i
equatorial boat chair forms (a-BC
e-BC). Accord-
Me
Me
Me
ing to [11], such a form is characterized by the low
XXIII
XXIV, XXV
5
value (0.2 0.5 ppm) and JHP 2 Hz. To determine
S
the steric structure of such compounds in more detail,
we performed single crystal X-ray diffraction study
of 1,3,2-diazaphosphocane VI. The general view of
the molecule of VI is shown in Fig. 1. The atomic
coordinates, interatomic distances, and bond angles
are given in Tables 1 3. The eight-membered hetero-
ring has the distorted boat chair conformation (Fig. 2).
Pr-i
N
S
CH2
P
NR2
Pr-i
N
Me
XXVI, XXVII
R = Me (XXIV, XXVI), R2 = CH2 CH2 (XXV, XXVII).
The obtained derivatives of three-coordinate phos-
phorus XXIV and XXV were stabilized as thiophos-
phoryl compounds XXVI and XXVII.
Thus, using a procedure based on cyclophosphor-
ylation of diamines I and II, we obtained a series of
1,3,2-diazaphosphocanes with phosphorus-containing
functional groups. All the obtained P(V) derivatives of
4,5;7,8-dibenzo-1,3,2-diazaphosphocanes are crystal-
line compounds, which were purified either by crystal-
lization from appropriate solvents or by column
chromatography on silica gel. The composition, struc-
ture, and purity of the compounds obtained were con-
1
firmed by elemental analysis, TLC, H, 13C, and 31P
NMR spectroscopy, and mass spectrometry. Thio-
phosphates VI, XVIII, and XXVI were also studied
by single crystal X-ray diffraction.
Fig. 1. General view of the molecule of VI.
Major attention was given to determining the steric
structure of the products in the crystalline state and in
solutions. The H N P and i-Pr N P systems strongly
differ in their structural features, and it is appropriate
to consider them separately.
1
The H NMR spectrum of 1,3-dihydro-1,3,2-diaza-
phosphocanes at room temperature is presented by one
set of signals of all groups of protons, characterizing
a certain averaged configuration. The integral inten-
sities of the signals are consistent with this assign-
ment. In the cyclic system, the signals of the methyl-
ene protons in the 6-position of the heteroring become
magnetically nonequivalent; the difference
in
the chemical shifts of these two protons allows certain
conclusions about the presence or absence of one or
another conformer or the conformational balance.
Fig. 2. Conformation of the heteroring in the molecule
of VI.
The value
0.21 ppm for 2-(4-methylphenoxy)-1,3-
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

196
NIFANT’EV et al.
2
Table 1. Atomic coordinates ( 104) and their equivalent isotropic temperature factors (
103) of VI
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
P
S
O
1510(1)
1005(1)
2812(2)
1317(4)
928(3)
3464(3)
3281(5)
4016(5)
4925(4)
5093(5)
4362(4)
1908(4)
1590(4)
2217(5)
3367(1)
2310(1)
3551(2)
3712(2)
3901(2)
3514(2)
3032(3)
3025(4)
3481(3)
3974(4)
4004(3)
4368(3)
5103(3)
5718(3)
2460(1)
2582(2)
2635(3)
927(5)
3609(5)
3827(5)
4897(6)
6003(7)
6080(6)
5001(7)
3871(6)
405(5)
54(1)
73(1)
57(1)
63(1)
60(1)
50(1)
76(2)
84(2)
71(1)
84(2)
71(1)
59(1)
58(1)
70(2)
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
3102(6)
3370(6)
2765(5)
1220(3)
1079(3)
1317(4)
1678(4)
1813(4)
1601(4)
659(4)
5638(3)
4892(4)
4272(4)
4665(2)
5304(3)
6027(3)
6137(3)
5492(3)
4755(3)
5233(3)
3462(8)
6314(5)
6933(4)
544(5)
926(7)
486(6)
78(2)
84(2)
76(2)
53(1)
56(1)
58(1)
67(1)
70(1)
63(1)
64(1)
105(3)
113(3)
99(2)
N1
N2
C1
C2
C3
C4
C5
C6
C7
C8
C9
4077(5)
3240(5)
3775(6)
5098(6)
5933(6)
5419(6)
1771(6)
7293(9)
991(10)
5651(10)
5723(7)
3796(10)
1908(8)
799(5)
323(6)
Table 2. Selected interatomic distances (d, ) in the molecule of VI
Bond
d
Bond
d
Bond
d
Bond
d
Bond
d
P O
1.601(3)
1.623(5)
1.628(4)
1.9349(16)
1.387(5)
1.441(6)
N2 C13
C1 C2
C1 C6
C2 C3
C3 C4
C4 C5
1.440(6)
1.360(7)
1.373(7)
1.377(8)
1.349(8)
1.376(9)
C4 C20
C5 C6
C7 C12
C7 C8
C8 C9
C8 C19
1.503(9)
1.392(8)
1.377(8)
1.388(6)
1.392(7)
1.504(7)
C9 C10
1.385(8)
C14 C15 1.385(7)
C14 C19 1.513(7)
C15 C16 1.365(7)
C16 C17 1.391(8)
C16 C22 1.505(8)
C17 C18 1.394(7)
P N1
P N2
P S
C10 C11 1.385(8)
C10 C21 1.510(9)
C11 C12 1.373(9)
C13 C14 1.385(7)
C13 C18 1.387(7)
O C1
N1 C7
Table 3. Selected bond angles ( , deg) in the molecule of VI
Angle
Angle
Angle
Angle
Angle
OPN1
OPN2
N1PN2
OPS
98.0(2)
C2C1C6
119.9(5) C1C6C5
125.0(4) C12C7C8
115.0(4) C12C7N1
119.7(5) C8C7N1
122.6(6) C7C8C9
117.1(5) C7C8C19
118.6(5) C9C10C21
122.6(6) C13C14C19 121.7(4)
104.46(19) C2C1O
120.2(5) C11C10C21 120.8(7) C16C15C14 122.7(5)
120.8(4) C12C11C10 121.2(6) C15C16C17 118.2(5)
111.9(2)
C6C1O
119.27(14) C1C2C3
111.67(16) C4C3C2
110.81(17) C3C4C5
119.0(5) C11C12C7
121.0(6) C15C16C22 121.2(6)
N1PS
117.0(5) C14C13C18 120.0(4) C17C16C22 120.6(6)
N2PS
121.8(5) C14C13N2
121.0(5) C18C13N2
121.6(4) C16C17C18 120.6(6)
C1OP
C7N1P
C13N2P
127.5(3)
123.9(3)
129.5(3)
C3C4C20 121.9(7) C9C8C19
C5C4C20 120.9(7) C10C9C8
118.4(4) C13C18C17 119.7(5)
124.0(5) C15C14C13 118.7(5) C8C19C14
112.1(4)
C4C5C6
121.9(6) C9C10C11 116.5(5) C15C14C19 119.5(5)
The atomic fragments N1N2C7C8C13C14 are planar
within 0.1816 . The deviations ( ) are 0.1880
for N1, 0.0730 for N2, 0.2864 for C7, 0.1015
for C8, 0.2583 for C13, and 0.1822 for C14. The P
and C19 atoms deviate from this plane by 0.4241 and
0.9833 , respectively. The conformation of the ring
is distorted, because the N1 and N2 atoms deviate
from the mean plane by different distances ( 0.188
and 0.073 , respectively). The bond angles at nitro-
gen atoms C7N1P (123.9 ) and C13N2P (129.5 ) differ.
These values show that both nitrogen atoms have the
hybridization close to sp2.
The deviations of the S and O atoms from the mean
plane of the heterocycle are 0.02 and 1.94 , respec-
tively, which is indicative of their equatorial (P S)
and axial (OPhCH3) location. The protons of the
methylene group (at the C19 atom) are located at
almost equal distances from the central plane (H191 at
1.57
and H192 at 1.48 ). Therefore, their loca-
tion cannot be considered as preferably axial or equa-
torial. The distance between the oxygen atom and the
nearest proton of the amido group is 3 , which rules
out hydrogen bonding in this part of the molecule.
The four-coordinate phosphorus atom in VI has
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
197
the usual distorted tetrahedral surrounding. The in-
teratomic distances P N1 [1.623(5) ] and P N2
[1.628(4) ] are practically equal, and all the bonds
of phosphorus are somewhat longer compared to
metric location relative to the heteroring plane. In this
case the CH2 protons give a doublet of doublets,
0.15 ppm. It is interesting that 10 15 min after the
dissolution the proton signals of the symmetric form
practically disappear.
the usual values [P S 1.9349(16), P O 1.601(3)
]
[12]. The angles at phosphorus (N1PN2 111.9 , SPO
119.27 ) are considerably larger than the endocyclic
OPO and NPN angles in six- and seven-membered
heterorings [13, 14], as well as in eight-membered
dioxa derivatives [15]. This fact is indicative of con-
siderable flattening of the phosphamide fragment. The
1
The same dynamics is observed in the H NMR
spectra of the other esters of the 1,3-diisopropyl-1,3,2-
diazaphosphocane series (XVI, XVII, XX).
If the alkoxy or aroxy group at phosphorus is sub-
stituted by methyl radical, an equilibrium is estab-
distance between the two benzene rings in the exo- lished in solution between forms A and B of 2-meth-
cyclic groups of the neighboring molecules is 5.54
,
yl-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -dimethyl-
which rules out intermolecular interactions. The di-
ameter of the cavity (the distance between C19 and P)
is 3.453 . The distances between the methylene
protons and the phosphorus atom are the following:
1,3,2-diazaphosphocane 2-oxide XXII. According to
1
the H NMR spectra, the ratio of these forms im-
mediately after the dissolution is 85 : 15. With time,
the equilibrium ratio of 68 : 32 is attained. Further
heating or increasing the acidity of the medium by
adding trifluoroacetic acid does not alter this ratio
even in the course of 1 month. This means that the
system exists in the stable equilibrium. These two
forms considerably differ in characteristics of iso-
propyl radicals and methylene groups. In the major
form A the two isopropyl groups are magnetically
equivalent, which suggests their symmetric location
relative to the heteroring plane. One of the methylene
H191 P 3.165
and H192 P 4.384
.
Thus, in the crystalline state 1,3-dihydro-1,3,2-di-
azaphosphocane 2-sulfide VI is in e-BC conformation,
whereas in solutions of thiophosphates V and VI
the e-BC
a-BC equilibrium probably takes place.
As the transfer from one conformation to another is
1
fast, the H NMR spectrum corresponds to the aver-
aged form.
5
Introduction of two isopropyl groups to the nitro-
gen atoms of 1,3,2-diazaphosphocanes considerably
alters the steric arrangement of the eight-membered
heterocycles under study. The 1H and 31P NMR
spectra show that these systems are conformationally
heterogeneous in solution at room temperature. The
bulky isopropyl substituents inhibit the conformational
transitions, so that it becomes possible to observe
them in the NMR time scale. Note that the solvent
does not significantly influence these conformational
transitions. The NMR spectra were recorded in CDCl3
and DMSO-d6.
protons has the coupling constant JHP 3.4 Hz,
1.08 ppm. In the minor form B all four methyl groups
of the isopropyl substituent are nonequivalent, which
proves their asymmetric location relative to the het-
eroring plane. Both protons of the methylene ring give
a doublet of doublets. No coupling constant JPH is
revealed,
0.16 ppm. Using saturation transfer, we
found that in a solution of phosphonate XXII isopro-
pyl substituents of both symmetric and asymmetric
forms are simultaneously involved in the exchange.
For example, at 360 K in DMSO solution irradia-
tion of the methyl signal with
0.95 ppm causes
the integral intensity of the signals with 0.45 and
1.34 ppm to considerably decrease. At the excita-
tion of the CH signals of the isopropyl group in the
symmetric form, the response of both CH proton sig-
nals is observed in the asymmetric form.
The conformational pattern of 1,3-diisopropyl-
1,3,2-diazaphosphocanes in solution depends on sub-
stituent X at phosphorus.
1
The H NMR spectrum of solution of 2-phenoxy-
1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -dimethyl-1,3,2-
diazaphosphocane 2-sulfide XVIII, taken immediately
after the dissolution, contains a double set of signals
corresponding to the presence of two forms in the
1 : 1 ratio. For one of them (form A) the isopropyl
groups are located symmetrically relative to the hetero-
ring plane. The CH2 protons in the 6-position of the
2
Thus, for form A in the cases under study JHH
5
11.9 12.1 Hz, JPH 3.4 3.48 Hz, and the methylene
protons show a considerable magnetic nonequivalence
(
1.08 1.15 ppm). These facts allow us to identify
this form as symmetric boat chair conformation.
The synchronous inversion of two nonplanar nitrogen
atoms takes place in solution, resulting in inter-
conversion of the symmetric and asymmetric forms.
In the process, the heteroring conformation is
ring give two doublets. One of them has the coupling
5
constant JHP 3.4 Hz,
1.15 ppm. In the other form
(B), all four methyl groups of the isopropyl substit-
uents are nonequivalent, which suggests their asym-
altered. This fact is confirmed by changes in
and
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198
NIFANT’EV et al.
To conclude, phosphonate XXII presumably exists
in the conformation equilibrium a-B BC e-B.
Evidently, the methyl group at the phosphorus atom
has such steric orientation that all the three conforma-
tions appear to be relatively favorable, and the transi-
1
tion of one form into another can be monitored by H
NMR spectroscopy at room temperature.
We believe that for phosphorodiamidites the equi-
librium a-B
e-B is attained in solutions. The transi-
tion of one form to another occurs through the BC
conformation at such a rate (this conformation is un-
favorable for such systems in solution) that it cannot
be detected in the NMR time scale.
As form A in phosphorodiamidites is observed
only at the initial moment after dissolution, the cor-
responding conformation is presumably stable in
the crystalline state. To confirm this hypothesis, we
studied by X-ray diffraction 2-phenoxy-1,3-diisopro-
pyl-4,5;7,8-dibenzo-11,11 -dimethyl-1,3,2-diazaphos-
phocane 2-sulfide XVIII. The general view of the
molecule is shown in Fig. 3. The atomic coordinates,
interatomic distances, and bond angles are listed in
Tables 4 6.
Fig. 3. General view of the molecule of thiophosphate
XVIII.
the coupling constant of the methylene protons. For
2
the asymmetric form B JHH 14.9 Hz,
0.15
0.16 ppm. These values evidently correspond to the
equilibrium e-B a-B.
2
Table 4. Atomic coordinates ( 104) and equivalent isotropic temperature factors (
103) of XVIII
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
S
2865(1)
2922(1)
3072(2)
4253(2)
1441(2)
4175(3)
4255(3)
5304(4)
6245(4)
6140(4)
5112(3)
4816(3)
6086(4)
6695(4)
6075(4)
4775(4)
9936(2)
7972(2)
7433(2)
7251(4)
7226(4)
7663(5)
6777(6)
6942(7)
7968(6)
8828(6)
8703(5)
5965(7)
5896(8)
4706(10)
3455(9)
3498(8)
1504(1)
1399(1)
842(1)
1757(1)
1449(1)
575(1)
184(1)
105(1)
4(2)
394(2)
685(1)
1629(1)
1467(1)
1368(1)
1422(1)
1579(1)
74(1)
54(1)
61(1)
44(2)
47(2)
58(1)
80(2)
103(2)
91(2)
88(2)
79(2)
48(2)
53(3)
52(3)
43(3)
49(3)
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C26
C27
4147(3)
1027(3)
4(3)
4732(8)
5950(7)
5917(7)
4716(9)
3474(8)
3502(7)
4706(8)
4641(5)
2097(8)
2128(9)
7857(4)
6805(6)
8529(7)
7862(4)
6832(6)
8637(6)
1679(1)
1207(1)
784(2)
43(2)
49(2)
58(3)
57(3)
50(3)
49(2)
52(2)
52(2)
83(3)
87(3)
55(1)
88(2)
82(2)
63(1)
73(2)
84(2)
P
O
N1
N2
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
456(4)
118(4)
1159(3)
1603(3)
2732(2)
6695(5)
325(6)
4823(3)
4873(5)
6219(4)
507(3)
9(4)
553(1)
713(1)
1137(2)
1383(1)
1838(1)
1323(2)
460(3)
2264(1)
2690(1)
2256(2)
1781(1)
2128(1)
1463(2)
681(3)
Table 5. Selected interatomic distances (d, ) in the molecule of XVIII
Bond
d
Bond
d
Bond
d
Bond
d
S P
1.9283(17)
1.5982(18)
1.655(3)
1.658(3)
1.403(3)
1.429(6)
1.499(4)
1.427(6)
1.501(4)
C1 C2
C1 C6
C2 C3
C3 C4
C4 C5
C5 C68
1.361(5)
1.371(4)
1.388(5)
1.363(6)
1.346(6)
1.371(4)
1.387(5)
1.383(7)
1.347(7)
C910C10
1.378(8)
1.409(6)
1.493(8)
1.393(7)
1.521(4)
1.387(7)
1.399(5)
1.361(7)
1.373(8)
C16 C17
C16 C21
C17 C18
C18 C19
C22 C23
C22 C24
C25 C26
C25 C27
1.407(6)
1.504(8)
1.379(7)
1.517(5)
1.519(5)
1.528(4)
1.499(5)
1.536(5)
P O
C10 C11
P N2
C
C20
P N1
C11 C12
C12 C19
C13 C18
C13 C14
C14 C15
C15 C16
O C1
N1 C722
N1 C13
C7
C
N2
C
C7 C12
C8 C9
N2 C25
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
Table 6. Selected bond angles ( , deg) in the molecule of XVIII
199
Angle
Angle
Angle
Angle
OPN2
97.74(13)
102.55(13)
113.82(16)
117.76(9)
112.12(13)
111.93(14)
126.96(19)
116.7(2)
122.45(19)
120.5(3)
117.5(2)
122.8(2)
119.6(3)
C9C10C11
C9C10C20
C11C10C20
C12C11C10
C7C12C11
C7C12C19
C11C12C19
C18C13C14
C18C13N2
C14C13N2
C15C14C13
C14C15C16
C15C16C17
116.3(7)
124.1(5)
119.6(7)
122.2(7)
119.6(4)
123.2(6)
117.1(6)
117.6(6)
121.9(4)
120.5(6)
122.1(6)
121.4(5)
116.7(7)
C2C1C6
C2C1O
121.0(3)
115.0(3)
124.0(3)
118.9(5)
120.6(5)
119.2(4)
121.9(5)
118.5(4)
117.1(6)
121.2(6)
121.7(4)
123.6(6)
121.2(5)
C15C16C21
C17C16C21
C18C17C16
C17C18C13
C17C18C19
C13C18C19
C18C19C12
N1C22C23
N1C22C24
C23C22C24
C26C25N2
C26C25C27
N2C25C27
123.1(6)
OPN1
120.2(7)
122.6(6)
119.5(5)
119.1(6)
121.4(6)
111.9(2)
111.7(3)
111.9(3)
111.6(3)
112.4(4)
111.3(3)
111.3(3)
N2PN1
OPS
C6C1O
C1C2C3
C4C3C2
C5C4C3
C4C5C6
C5C6C1
C8C7C12
C8C7N1
C12C7N1
C9C8C7
C8C9C10
N2PS
N1PS
C1OP
C7N1C22
C7N1P
C22N1P
C13N2C25
C13N2P
C25N2P
In the eight-membered heterocycle the atomic frag-
Thus, the conformation of the heteroring in the crys-
talline state corresponds to the conformation of form
A in solution.
ments N1N2C7C12C13C18 are planar within 0.1805
.
The P and C19 atoms deviate from this plane by
0.4858 and 0.9919 , respectively. The heteroring
has a symmetric boat chair conformation (Fig. 4).
This is confirmed by the fact that the angles C7N1P
and C13N2P are practically equal and have the values
of 122.45 and 122.8 , respectively. The deviation of
1
Quite a different pattern is observed in the H
NMR spectra of cyclic triamides XIX and XXVI.
Immediately after the dissolution of crystalline 2-di-
methylamino-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide XXVI in
DMSO-d6, only one form is observed at room tem-
perature. The character of splitting and the number of
sulfur from the mean plane of the ring is 0.36
,
which suggests its pseudoequatorial orientation. The
deviation of the phenoxyl oxygen is 1.94 . Thus, the
exocyclic substituent has axial orientation relative to
the ring plane. The methylene protons H191 and H192
deviate from the central plane by 1.56 and 1.60
.
Therefore, it cannot be considered that the axial or
equatorial location of these atoms is preferred. The
angles at nitrogen atoms are close to those typical of
the trigonal planar configuration (the sum of bond
angles is 359.7 at N1 and 359.92 at N2). The four-
coordinate phosphorus atom has the distorted tetra-
hedral surrounding. The interatomic distances P N1
(1.658 ) and P N2 (1.655 ) are practically equal.
All the bonds at the phosphorus atom are longer
than the standard values [P S 1.9283(17) , P O
1.5982(18) ]. The angles at the phosphorus atom,
N1PN2 (113.82 ) and SPO (117.76 ), demonstrate
strong flattening of the phosphamide part of the ring
as compared to the corresponding 1,3,2-diazaphos-
phepanes [16].
The distances through the space between the meth-
ylene protons and phosphorus atom ( ) are as fol-
lows: P H191 4.43 and P H192 3.10. The distance
between the P and C19 atoms is 3.453
.
In the crystalline state, the two isopropyl groups
are located symmetrically relative to the ring plane.
Fig. 4. Conformation of the heteroring in the molecule
of XVIII.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

200
NIFANT’EV et al.
methyl signals suggest asymmetric location of the iso-
propyl groups relative to the ring plane. Using satura-
tion transfer at 340 K for the CH and CH3 protons
of the isopropyl group, we revealed slow (in the NMR
time scale) exchange between the two isopropyl
groups. We found that the methyl signal with
0.35 ppm is coupled with the methyl signal with
0.79 ppm. Heating of solution to 380 K does not
noticeably alter the spectrum, which suggests that
the exchange remains slow. Study of the solution
of cyclic triamide XXVI in the temperature range
290 380 C in the presence of a tenfold excess of tri-
fluoroacetic acid revealed no apparent changes as
compared to the spectra taken in the absence of the
acid. This form is characterized by strong nonequiv-
alence of the methylene protons,
1 ppm, and the
2
presence of the geminal constant JHH 14.7 Hz. These
data show that the conformation of the cycle in solu-
tion is e-B, and it is fairly rigid [17]. This hypothesis
was confirmed by X-ray diffraction study of cyclic
phosphorothioic triamide XXVI. The general view of
the molecule is shown in Fig. 5. The atomic coordina-
tes, interatomic distances, and bond angles are listed
in Tables 7 9.
Fig. 5. General view of the molecule of phosphorothioic
amide XXVI.
2
Table 7. Atomic coordinates ( 104) and equivalent isotropic temperature factors (
103) for XXVI
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
S
6333(1)
5204(1)
4856(2)
4323(1)
5297(1)
3903(2)
3008(2)
2585(2)
3029(2)
3923(2)
4373(2)
5361(2)
5957(2)
5952(2)
4160(1)
3644(1)
3944(1)
3835(1)
2643(1)
3215(1)
3017(2)
2430(2)
2014(1)
2206(2)
2791(1)
2913(2)
2325(1)
2244(1)
6990(1)
7242(1)
8024(1)
6727(1)
7220(1)
6307(1)
6430(1)
6032(1)
5510(1)
5405(1)
5791(1)
5663(1)
6052(1)
6786(1)
54(1)
40(1)
53(1)
38(1)
41(1)
36(1)
43(1)
48(1)
46(1)
43(1)
37(1)
40(1)
39(1)
40(1)
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
6565(2)
7159(2)
7165(2)
6568(2)
2582(3)
7808(3)
4125(2)
4503(2)
3139(2)
4620(2)
4902(3)
4394(2)
3929(2)
5501(3)
1728(2)
1276(2)
1332(2)
1863(2)
1370(2)
850(3)
4701(2)
4924(2)
4911(2)
2131(2)
1947(3)
1370(2)
3952(3)
4166(3)
7099(2)
6705(2)
5980(2)
5674(2)
5076(2)
5537(2)
6550(1)
5838(2)
6604(2)
7597(1)
8352(2)
7200(2)
8262(2)
8575(2)
50(1)
54(1)
50(1)
46(1)
65(1)
72(1)
44(1)
51(1)
57(1)
50(1)
69(1)
62(1)
72(1)
78(1)
P
N1
N2
N3
C1
C2
C3
C4
C5
C6
C7
C8
C9
Table 8. Selected interatomic distances (d, ) in the molecule of XXVI
Bond
d
Bond
d
Bond
d
Bond
d
S P
1.9474(14)
1.648(4)
1.663(3)
1.667(3)
1.455(6)
1.468(6)
1.442(5)
1.501(5)
N3 C9
N3 C19
C1 C2
C1 C6
C2 C3
C3 C4
C4 C5
C4 C14
1.439(5)
1.500(5)
1.393(6)
1.394(5)
1.384(6)
1.376(6)
1.384(6)
1.503(7)
C5 C6
1.389(5)
1.506(5)
1.512(5)
1.387(6)
1.400(5)
1.384(6)
1.380(6)
1.380(6)
C12 C13
C12 C15
C16 C17
C16 C18
C19 C21
C19 C20
1.380(6)
1.504(7)
1.510(6)
1.514(6)
1.507(7)
1.525(7)
P N1
C6 C7
P N3
C7 C8
P N2
C8 C13
C8 C9
N1 C22
N1 C23
N2 C1
N2 C16
C9 C10
C10 C11
C11 C12
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
Table 9. Selected bond angles ( , deg) in the molecule of XXVI
201
Angle
Angle
Angle
Angle
N1PN3
110.37(17)
102.95(17)
103.92(16)
111.15(15)
110.97(12)
116.98(12)
113.4(5)
125.6(4)
120.8(4)
118.0(3)
122.1(2)
C4C5C6
C5C6C1
C5C6C7
C1C6C7
C6C7C8
C13C8C9
C13C8C7
C9C8C7
C10C9C8
C10C9N3
C8C9N3
C11C10C9
123.2(4)
118.7(4)
118.7(4)
122.6(4)
114.2(3)
117.7(4)
119.2(4)
123.1(4)
118.9(4)
119.0(4)
122.0(3)
121.7(5)
C9N3C19
C9N3P
118.1(3)
121.9(2)
119.6(3)
118.8(4)
119.3(3)
121.8(3)
120.6(4)
121.7(4)
116.9(4)
122.4(4)
120.7(4)
C10C11C12
C13C12C11
C13C12C15
C11C12C15
C12C13C8
N2C16C17
N2C16C18
C17C16C18
N3C19C21
N3C19C20
C21C19C20
120.5(4)
N1PN2
N3PN2
N1PS
117.3(4)
120.9(5)
121.7(5)
123.8(4)
111.1(3)
113.3(4)
111.4(4)
112.6(4)
112.0(4)
111.5(4)
C19N3P
C2C1C6
C2C1N2
C6C1N2
C3C2C1
C4C3C2
C3C4C5
C3C4C14
C5C4C14
N3PS
N2PS
C22N1C23
C22N1P
C23N1P
C1N2C16
C1N2P
C16N2P
117.8(3)
Two phenyl rings in the molecule are planar, ring
A within 0.0064 , and ring B within 0.0074
The diameter of the cavity conventionally charac-
terized by the distance between phosphorus and C7 is
.
The angle between the planar fragments is 73.4 .
The eight-membered heteroring has the distorted boat
conformation (Fig. 6). The N3C1C6C8C9 atomic
fragment is planar within 0.0985 . The P, N2, and C7
atoms deviate to one side of this plane by 1.43, 1.2286,
and 0.69 , respectively. The deviation of the sulfur
atom from the mean plane is 2.96 , which suggests
its axial location. The nitrogen atom of the exocyclic
substituent deviates from the mean plane by 1.53
(it lies almost in the same plane with the phos-
phorus atom). Thus, the dimethylamino group has the
equatorial location. The methylene protons H71 and
3.24
.
Thus, 2-dimethylamido-1,3-diisopropyl-4,5;7,8-di-
benzo-11,11 -dimethyl-1,3,2-diazaphosphocane 2-sul-
fide XXVI in solution preserves the distorted e-B con-
formation characteristic of the crystalline state. The
exchange between two isopropyl groups occurring in
solution suggests formation of the equilibrium mix-
ture of the two conformers. However, the content of
the second conformer a-B is so small that it practical-
ly does not affect the purity of the e-B form. This
fact is also proved by the low rate of exchange pro-
cesses.
H72 deviate from the central plane by 1.59 and 0.76
,
respectively. Hence, the H71 proton is axial, and
the H72 proton is equatorial relative to the mean plane.
Two isopropyl groups are located asymmetrically rel-
ative to the heteroring plane. The bond angles at the
ring nitrogen atoms are close to those typical of sp2
hybridization; these atoms have trigonal planar co-
ordination. The sum of the bond angles is 357.8 at
N2 and 359.6 at N3. The nitrogen atom of the exo-
cyclic P N bond also has the trigonal planar coordina-
tion (the sum of bond angles is 359.8 ). The four-co-
ordinate phosphorus atom has the distorted tetragonal
coordination. The interatomic distances P N2 and
P N3 are practically equal. All the bonds of the
EXPERIMENTAL
1
The H NMR spectra were measured on Bruker
WM-250 (250.13 MHz) and Bruker WM-400
(400.13 MHz) spectrometers against internal TMS
and the residual signals of solvents (DMSO 2.5 ppm,
CDCl3 7.27 ppm). The signals were assigned using
phosphorus atom [P S 1.9474(14), P N1 1.648(4)
]
are somewhat longer compared to the standard
values. The angles at the phosphorus atom N2PN3
[103.92(16) ] and N1PS [111.15(15) ] are close
to those in some 1,3,2-diazaphosphorinanes [18, 19]
and phosphepanes [16], but are somewhat larger than
in the corresponding dioxa derivatives [20]. The dis-
tances between the methylene protons and the phos-
Fig. 6. Conformation of the heteroring in the molecule
of XXVI.
phorus atom ( ) are H71 P 2.81 and H72 P 4.2.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

202
NIFANT’EV et al.
double homonuclear resonance. The 13C NMR spectra
were recorded on a Bruker AC-200P (50.32 MHz)
spectrometer. The 31P NMR spectra were obtained on
a Bruker WP-80 SY spectrometer (32.4 MHz) against
external 85% orthophosphoric acid.
extract was dried over anhydrous calcium chloride,
the solvent was removed, and the final product was
isolated by column chromatography on silica gel.
1
Yield 65%, mp 78 79 C, Rf 0.91 (A). H NMR spec-
trum, , ppm: 1.00 d [12H, (CH3)2CH], 2.12 s
(6H, CH3 Ar), 3.48 q [2H, (CH2)2CH], 3.59 s
(2H, CH2), 6.50 d (2Hb, Ar), 6.76 s (2Ha, Ar),
6.90 d (2Hc, Ar).
Column chromatography was carried out on a col-
umn 15 mm in diameter, packed with silica gel C-300
L 45/75 m. The Rf values were determined by TLC
on Silufol UV-254 plates in the systems 5 : 1 ben-
zene dioxane (A), 3 : 1 hexane dioxane (B), and 1 : 3
benzene methylene chloride (C). The chromatograms
were developed with iodine vapor or by calcination
at 250 300 C.
2-X-1,3-Dihydro(-diisopropyl)-4,5;7,8-dibenzo-
11,11 -dimethyl-1,3,2-diazaphosphocane 2-sulfide
V, VI, and XV XIX (general procedure). To a solu-
tion of 0.01 mol of diamine I or II and 0.02 mol of
triethylamine in dry benzene, 0.01 mol of phosphorus
trichloride, alkyl or aryl phosphorodichloridite, or
phosphorodichloridous amide was slowly added with
stirring at 5 10 C. After that the reaction mixture was
stirred at room temperature for 2 3 h, and triethyl-
amine hydrochloride was filtered off. To the resulting
solution, sulfur was added, the reaction mixture was
stirred for 2 h, and the solvent was removed. The tar-
get product was isolated by recrystallization from
benzene (V, VI, XVII) or by column chromatography
(XV, XVI, XVIII, XIX).
All X-ray studies were carried out on a Syntex P-1
four-circle diffractometer (CuK radiation, /2 scan-
ning).
A 0.40 0.33 0.16-mm colorless transparent well-
faced crystal of thiophosphate VI, C22H23N2OPS,
has the following cell parameters: a 12.012(2),
b 17.334(3), c 9.770(2)
;
91.57(3) : M 394.45,
Z 4, dcalc 1.288 g/cm3, V 2033.5(6) 3, space
group P21/c. For the calculation and refinement,
2232 unique reflections with I > 2 (I) were used;
R 0.0678. The structure was solved by the direct
method using the SHELX 97 program.
2-Phenoxy-1,3-dihydro-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide V. Yield
90%, mp 211 212 C, Rf 0.74 (A), 0.55 (B). m/z 380.
1H NMR spectrum (CDCl3), , ppm: 2.29 s (6H,
The 0.36 0.22 0.16-mm crystal of XVIII,
C27H33N2OPS, is monoclinic with the following cell
CH131,11 ), 3.98 d (1H, CH2, JHH 13.2 Hz), 4.30 d.d
2
2
5
parameters: a 9.874(2), b 9.711(2), c 26.554(5)
;
(1H, CH2, JHH 13.2, JHP 2.6 Hz), 5.23 d (2H,
98.59(3) , M 464.58, Z 4, dcalc 1.226 g/cm3,
V 2517.6(9) , space group P21/n. For the calculation
and refinement, 2306 unique reflections with I > 2 (I)
were used; R 0.0894. The structure was solved by
the direct method using the SHELX 97 program.
NH1,3, JHNP 11.3 Hz), 6.68 7.14 m (11H, Ar).
2
(CHCl3) 58.43 ppm. Found, %: C 66.14; H 5.67;
P
P 8.01. C21H21N2OPS. Calculated, %: C 66.2; H 5.5;
P 8.1.
2(4-Methyl)-1,3-dihydro-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide VI.
Yield 92%, mp 213 214 C, Rf 0.89 (A), 0.77 (B).
1H NMR spectrum (CDCl3), , ppm: 1.28 s (3H,
CH3 C6H4 O), 2.27 s (3H, CH131), 2.3 s (3H, CH311 ),
The 0.45 0.34 0.28-mm crystal of phosphoro-
thioic amide XXVI, C23H34N3PS, is rhombic with the
following cell parameters: a 14.908(3), b 16.547(3),
c 18.988(3) ; M 415.56, Z 8, dcalc 1.179 g/cm3,
V 4684.0(15) 3, space group Pbca. For the calcula-
tion and refinement, 2148 unique reflections with I >
2 (I) were used; R 0.029. The structure was solved
by the direct method using the SHELX 97 prorgam.
2
4.05 d (1H, CH2, JHH 13.6 Hz), 4.26 d.d (1H, CH2,
5
2
2JHH 13.6, JHP 2.1 Hz), 5.19 d (2H, NH1,3, JPNH
13.5 Hz), 6.72 7.15 (10H, Ar). P (CHCl3) 59.14 ppm.
Found, %: C 66.61; H 5.95; P 7.39. C22H23N2OPS.
Calculated, %: C 67; H 5.84; P 7.86.
2,2 -Methylenebis-p-toluidine I was prepared as
described in [21].
2-Chloro-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide XV.
N,N -Diisopropyl-2,2 -methylenebis-p-toluidine
II. Isopropyl iodide, 0.374 mol, was added with stir-
ring to a solution of 0.017 mol of diamine I in 12 ml
of ethanol, and the resulting mixture was refluxed for
24 h. Then the reaction mixture was neutralized with
a concentrated ammonia solution at cooling with ice.
Organic substances were exracted with benzene, the
Yield 78%, mp 225 228 C. 1H NMR spectrum
a 2 3
(CDCl3), , ppm: 0.20 d (3H, CH3,
J
6.6 Hz),
HH
2
Two methyl groups of isopropyl radical in position 1 of the
ring are marked by a and b, and in position 3, by a and b .
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
203
0.79 d (3H, CH3a , JHH 6.6 Hz), 1.43 d (3H, CH3b,
6.8 Hz), 2.28 s (6H, CH311,11 ), 3.48 d (1H, CH2,
3
3JHH 6.6 Hz), 1.48 d (3H, CH3b , JHH 6.6 Hz), 2.29 s
2JHH 11.9 Hz), 4.63 d.d (1H, CH2, JHH 11.9, JHP
3
2
5
(3H, CH311), 2.34 s (3H, CH311 ), 3.68 m (1H, CHi-Pr,a,b
,
3.4 Hz), 5.02 m (2H, CH2i-Pr
,
3JHH 6.7, 6.8 Hz),
2
3JHH 6.6 Hz), 3.74 d (1H, CH2, JHH 13.8 Hz), 4.43 d
6.58 7.17 m (11H, Ar).
(C6H6) 62.28 ppm.
P
2
1
(1H, CH2, JHH 13.8 Hz), 4.56 m (1H, CHi-Pr,a ,b
,
Form B. H NMR spectrum (CDCl3), , ppm: 0.36 d
(3H, CH3a, JHH 6.8 Hz), 0.40 d (3H, CH3a , JHH
3
3
3JHH 6.6 Hz), 7.03 7.20 m (6H, Ar).
(CHCl3)
P
6.8 Hz), 1.39 d (3H, CH3b, JHH 6.4 Hz), 1.47 d (3H,
3
68.95 ppm.
CH3b, JHH 6.8 Hz), 2.06 s (3H, CH311), 2.10 s (3H,
3
2-Methoxy-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide XVI.
Yield 50%, mp 174 176 C, Rf 0.62 (A), 0.58 (B),
CH311 ), 4.10 m (1H, CHi-Pr,a,b
,
3JHP 15, JHH 6.8,
3
2
6.4 Hz), 4.12 d (1H, CH2, JHH 14.5 Hz), 4.27 d (1H,
2
3
CH23, JHH 14.5 Hz), 4.64 m (1H, CHi-Pr,a ,b , JHP
1
0.56 (C). H NMR spectrum (CDCl3), , ppm: 2.09 d
(3H, CH3 O), 0.34 d (3H, CH3a, JHH 6.4 Hz), 0.35 d
3
15, JHH 6.8 Hz), 6.78 7.34 m (11H, Ar).
(C6H6)
P
(3H, CH3a , JHH 6.4 Hz), 1.34 d (3H, CH3b, JHH
3
3
67.39 ppm.
6.8 Hz), 1.48 d (3H, CH3b , JHH 6.8 Hz), 2.16 s
3
2-Diethylamino-1,3-diisopropyl-4,5;7,8-diben-
zo-11,11 -dimethyl-1,3,2-diazaphosphocane 2-sul-
fide XIX. Yield 42%, mp 170 171 C, Rf 0.73 (A),
(6H, CH311,11 ), 3.50 d (1H, CH2, JHH 14.5 Hz),
2
3
3
3.96 m (1H, CHi-Pr,a,b, JHH 6.4, JHH 6.8 Hz), 4.12 m
3
3
(1H, CHi-Pr,a ,b , JHH 6.4 Hz, JHH 6.8 Hz), 4.17 d
1
m/z 443. H NMR spectrum (CDCl3), , ppm: 0.15 d
2
(3H, CH3a, JHH 6.4 Hz), 0.80 d (3H, CH3a , JHH
3
3
(1H, CH2, JHH 14.5 Hz), 6.56 7.06 m (6H, Ar).
(C6H6) 73.92 ppm.
P
3
5.9 Hz), 1.23 t (6H, CH3CH2, JHH 7.2 Hz), 1.27 m
(6H, CH3i-Pr,b,b 3JHH 6.4 Hz), 2.28 s (3H, CH311),
,
2-Ethoxy-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide XVII.
Yield 45%, mp 164 166 C, Rf 0.93 (A), 0.96 (B),
0.66 (C), m/z 416. Form A. 1H NMR spectrum
2.23 s (3H, CH311 ), 3.16 m (1H, CHi-Pr,a,b
,
3JHH
3
3
6.4 Hz), 3.25 m (2H, CH2CH3, JHH 7.2, JHP
12.8 Hz), 3.48 m (2H, CH2CH3, JHH 7.2, JHP
3
3
2
(CDCl3), , ppm: 0.75 t (3H, OCH2CH3, 3JHH 7.2 Hz),
13.2 Hz), 3.79 d (1H, CH2, JHH 14.7 Hz), 4.03 m
(1H, CHi-Pr,a ,b
,
3JHH 6.4 Hz), 4.64 d (1H, CH2,
0.99 d (6H, CH3a,a , JHH 6.4 Hz), 1.28 d (6H, CH3b,b
,
3
2JHH 14.7 Hz), 6.97 7.12 m (6H, Ar).
(CHCl3)
3JHH 6.4 Hz), 2.31 s (6H, CH311,11 ), 3.45 d (1H,
P
2
3
70.97 ppm.
CH2, JHH 11.9 Hz), 3.72 m (2H, CH3CH2O, JHP
2
9.4 Hz, 3JHH 7.2 Hz), 4.31 d.d (1H, CH2, JHH 11.9,
2-Ethoxy-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-oxide XX.
a. Through a solution of 0.01 mol of diazaphospho-
cane XII in 20 ml of anhydrous benzene, dry NO
was passed for 15 min. The solvent was removed,
and the residue purified chromatographically on a sil-
ica gel column, elution with 1 : 1 benzene dioxane.
3
5JHP 3.4 Hz), 4.89 m (2H, CH2i-Pr, JHP 13.2 Hz,
3JHH 6.4 Hz), 6.94 7.11 m (6H, Ar).
(CHCl3)
P
1
71.14 ppm. Form B. H NMR spectrum (CDCl3),
, ppm: 0.25 d (3H, CH3a, JHH 6.8 Hz), 0.28 d
3
(3H, CH3a , JHH 6.8 Hz), 1.11 t (3H, CH3CH2O JHH
3
3
6.8 Hz), 1.35 d (3H, CH3b, JHH 6.8 Hz), 1.44 d (3H,
3
Yield 57%, mp 182 183 C, Rf 0.55 (A).
(C6H6)
P
CH3b, JHH 6.8 Hz), 2.28 s (6H, CH311,11 ), 3.77 m
3
10.83 ppm.
3
(1H, CHi-Pr,a,b
,
3JHP 15.3, JHH 6.8 Hz, 6.8 Hz),
b. To a solution of 0.01 mol of diazaphosphocane
XII in 20 ml of anhydrous benzene, 0.01 mol of
a complex of hydrogen peroxide with urea was added,
and the resulting mixture was stirred for 2 h. The un-
changed complex was filtered off, and the filtrate was
evaporated. The residue was purified on a silica gel
column, elution with 1 : 1 benzene dioxane. Yield
3
3
3.90 m (1H, CHi-Pr,a ,b , JPH 15.3, JHH3 6.8, 6.8 Hz),
3
3.95 m (2H, CH3CH2O, JHP 8.5, JHH 6.8 Hz),
2
4.04 d (1H, CH2, JHH 14.5 Hz), 4.17 d (1H, CH2,
2JHH 14.5 Hz), 6.94 7.11 m (6H, Ar),
(CHCl3)
P
71.51 ppm. Found, %: C 65.90; H 8.26; P 6.26.
C23H33N2OPS. Calculated, %: C 66.3; H 7.9; P 7.4.
1
52%, mp 182 183 C. Form A. H NMR spectrum
(CDCl3), , ppm: 0.86 t (3H, OCH2CH3, 3JHH 6.8 Hz),
2-Phenoxy-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-sulfide XVIII.
Yield 30%, mp 148 150 C, Rf 0.83 (A), 0.76 (B).
1.02 d (6H, CH3a,a , JHH 6.8 Hz), 1.36 d (6H, CH3b,b
,
3
3JHH 6.8 Hz), 2.3 s (6H, CH311,11 ), 3.45 d (1H, CH2,
3
2JHH 11.9 Hz), 3.71 m (2H, CH3CH2O, JHH 6.8 Hz),
1
Form A. H NMR spectrum (CDCl3), , ppm: 1.01 d
(3H, CH3a,a , JHH 6.7 Hz), 1.28 d (3H, CH3b,b , JHH
4.37 d.d (1H, CH2, JHH 11.9, JHP 3.4 Hz), 4.91 m
3
3
2
5
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

204
NIFANT’EV et al.
3
2
(2H, CH2i-Pr, JHH 6.8 Hz), 6.94 7.11 m (6H, Ar).
4.06 d (1H, CH2, JHH 14.9 Hz), 6.92 7.21 m (6H,
1
(CHCl3) 10.83 ppm. Form B. H NMR spectrum
Ar).
(CHCl3) 29.65 ppm.
P
P
(CDCl3), , ppm: 0.21 d (3H, CH3a, JHH 6.8 Hz),
3
1
Form A. H NMR spectrum (DMSO-d6), , ppm:
0.56 d (3H, CH3a , JHH 6.8 Hz), 1.03 t (3H,
3
0.60 d (3H, PCH3, JHP 15.3 Hz), 0.95 d (6H, CH3a,a
,
2
CH3CH2O, JHH 6.8 Hz), 1.37 d (3H, CH3b, JHH
3
3
3JHH 6.9 Hz), 1.23 d (6H, CH3b,b , JHH 6.5 Hz), 2.27 s
3
6.8 Hz), 1.41 d (3H, CH3b , JHH 6.4 Hz), 2.25 s (3H,
2
3
(6H, CH311,11 ), 3.56 d (1H, CH2, JHH 11.8 Hz),
CH311), 2.28 s (3H, CH311 ), 3.57 m (1H, CHi-Pr,a,b
,
2
5
4.26 d.d (1H, CH2, JHH 11.8, JHP 3.4 Hz), 4.40
4.53 m (2H, CH2i-Pr, JHH 6.9, 6.5 Hz), 6.96 br.s
3JHH 6.8, 6.8 Hz), 3.81 m (1H, CHi-Pr,a ,b , JHH 6.8,
3
3
2
6.4 Hz), 3.92 d (1H, CH2, JHH 14.6 Hz), 4.02 m
(2H, CH3CH2O, JHH 6.8 Hz), 4.14 d (1H, CH2,
2JHH 14.6 Hz), 6.94 7.11 m (6H, Ar).
1
(4H, Ar), 7.35 br.s (2H, Ar). Form B. H NMR spec-
3
trum (DMSO-d6), , ppm: 0.1 d (3H, CH3a, JHH
3
(CHCl3)
6.5 Hz), 0.45 d (3H, CH3a , JHH 6.5 Hz), 1.25 d
3
P
11.71 ppm.
(3H, CH3b), 1.33 d (3H, CH3b ), 1.60 d (3H, PCH3,
2JHP 14.9 Hz), 2.23 s (3H, CH311), 2.25 s (3H, CH311 ),
2-Methylthio-1,3-diisopropyl-4,5;7,8-dibenzo-
11,11 -dimethyl-1,3,2-diazaphosphocane 2-oxide
XXI. A mixture of 0.01 mol of thiophosphate
XVII and 0.015 mol of methyl iodide was refluxed in
30 ml of benzene for 8 h. After that the solvent was
distilled off. The residue was recrystallized from ben-
zene. Yield 89%, mp 192 193 C, Rf 0.49 (A),
3.40 3.55 m (1H, CHi-Pr,a ,b
,
3JHH 6.5 Hz), 3.58
3.70 m (1H, CHi-Pr,a,b, JHH 6.5 Hz), 3.81 d (1H,
3
2
2
CH2, JHH 14.1 Hz), 4.19 d (1H, CH2, JHH 14.1 Hz),
6.90 7.15 m (6H, Ar). Found, %: C 70.95; H 8.7;
P 8.57. C22H31N2OP. Calculated, %: C 71.35; H 8.37;
P 8.37.
1
0.44 (B). H NMR spectrum (CDCl3), , ppm: 0.04 d
1,3-Diisopropyl-4,5;7,8-dibenzo-11,11 -dimethyl-
1,3,2-diazaphosphocane 2-oxide XXIII. To a solu-
tion of 0.005 mol of crude acid chloride X in 8 ml of
benzene, a mixture consisting of 0.005 mol of water,
0.005 mol of triethylamine, and 4 ml of dioxane was
gradually added at 5 10 C. The resulting mixture was
stirred at room temperature, triethylamine hydrochlo-
ride was filtered off, and the solvent was removed.
The substance was purified by column chromatog-
raphy on a silica gel column, elution with 1 : 1 ben-
zene dioxane. Yield 24%, mp 113 114 C, Rf 0.573
(6H, CH3a,a , JHH 6.8 Hz), 0.56 d (6H, CH3b,b , JHH
3
3
3
6.4 Hz), 1.39 d (3H, CH3S, JHP 6.8 Hz), 2.28 s (6H,
CH311,11 ), 3.63 m (1H, CHi-Pr,a,b 3JHH 6.8 Hz), 3.81 d
(1H, CH2, JHH 14.9 Hz), 4.04 m (1H, CHi-Pr,a ,b
,
2
3JHH 6.4 Hz), 4.31 d (1H, CH2, JHH 14.9 Hz), 6.93
2
7.22 m (6H, Ar).
(C6H6) 33.58 ppm.
P
2-Methyl-1,3-diisopropyl-4,5;7,8-dibenzo-11,11 -
dimethyl-1,3,2-diazaphosphocane 2-oxide XXII.
A mixture of 0.01 mol of diamido ester XII and
0.015 mol of methyl iodide was refluxed in 30 ml of
dry benzene for 2 h. After that the solvent was dis-
tilled off, and the residue was recrystallized from ben-
zene. Yield 80%, mp 206 208 C, Rf 0.068 (A),
0.12 (B). Form A. 1H NMR spectrum (CDCl3),
1
(A), 0.18 (B). Form A. H NMR spectrum (CDCl3),
, ppm: 1.11 d (6H, CH3a,a , JHH 6.8 Hz), 1.37 d (6H,
3
CH3b,b , JHH2 6.4 Hz), 2.27 s (6H, CH311,11 ), 3.48 d
3
2
(1H, CH2, JHH 11.9 Hz), 4.36 d.d (1H, CH2, JHH
11.9, JHP 3.8 Hz), 4.47 m (2H, CH2i-Pr, JHH 6.8,
5
3
2
2
6.4 Hz), 6.98 7.21 m (6H, Ar), 7.4 d (1H, PH, JHP
, ppm: 0.76 d (3H, PCH3, JHP 15.3 Hz), 1.02 d
1
(6H, CH3a,a , JHH 6.8 Hz), 1.32 d (6H, CH3b,b , JHH
3
3
599.2 Hz).
(CHCl3) 11.16 ppm. Form B. H NMR
P
spectrum (CDCl3), , ppm: 0.45 d (3H, CH3a, JHH
3
6.4 Hz), 2.32 s (6H, CH311,11 ), 3.48 d (1H, CH2,
6.8 Hz), 0.70 d (3H, CH3a , JHH 6.8 Hz), 1.35 d
3
2JHH 11.9 Hz), 4.40 d.d (1H, CH2, JHH 11.9, JHP
2
5
(3H, CH3b, JHH 6.4 Hz), 1.40 d (3H, CH3b , JHH
3
3
3.4 Hz), 4.63 m (2H, CH2i-Pr
,
3JHH 6.8, 6.4 Hz),
6.8 Hz), 2.30 s (3H, CH311), 2.31 s (3H, CH311 ),
6.92 7.20 m (6H, Ar).
(CHCl3) 26.43 ppm.
P
3.66 m (1H, CHi-Pr,a,b, JHH 6.8, 6.4 Hz), 3.80 m
3
1
Form B. H NMR spectrum (CDCl3), , ppm: 0.22 d
(3H, CH3a, JHH 6.8 Hz), 0.45 d (3H, CH3a , JHH
3
3
(1H, CHi-Pr,a ,b , JHH 6.8 Hz), 3.87 d (1H, CH2, JHH
3
2
6.8 Hz), 1.37 d (3H, CH3b, JHH 6.4 Hz), 1.42 d (3H,
3
2
15.3 Hz), 4.02 d (1H, CH2, JHH 15.3 Hz), 6.98
7.21 m (6H, Ar), 6.27 d (1H, PH, JHP 613.7 Hz).
(CHCl3) 17.05 ppm.
CH3b , JHH 6.8 Hz), 1.61 d (3H, PCH3, JPH 14.5 Hz),
2
2
2
P
2.27 s (3H, CH311), 2.3 s (3H, CH311 ), 3.57 m (1H,
3
CH
,
i-Pr a ,b , JHH 6.8, 6.8 Hz), 3.71 m (1H, CHi-Pr,a,b
,
2-Dimethylamino-1,3-diisopropyl-4,5;7,8-diben-
zo-11,11 -dimethyl-1,3,2-diazaphosphocane 2-sul-
3JHH 6.8, 6.4 Hz), 3.9 d (1H, CH2, JHH 14.9 Hz),
2
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

HIGHER 1,3,2-DIAZAPHOSPHACYCLANES: V.
3JHH 6.8 Hz), 6.85 7.20 m (6H, Ar).
205
fide XXVI. To a solution of 0.01 mol of dimethyl-
amine in dry hexane, a solution of crude phosphoro-
chloridite X (0.005 mol) in dry benzene was slowly
added with stirring at 5 10 C. The resulting mixture
was stirred at room temperature for 1.5 h, and dimeth-
ylamine hydrochloride was filtered off. To a solution
of crude triamide XXIV, sulfur was added, and the re-
action mixture was stirred for 2 h. The solvent was re-
moved, and the phosphorothioic triamide was isolated
by column chromatography on silica gel, elution with
10 : 1 benzene dioxane. Yield 45%, mp 141 142 C,
(CHCl3)
P
1
81.67 ppm. Form B. H NMR spectrum (CDCl3),
, ppm: 0.13 d (3H, CH3a, JHH 6.4 Hz), 0.62 d
3
(3H, CH3a , JHH 6.4 Hz), 1.31 d (3H, CH3b, JHH
3
3
6.4 Hz), 1.41 d (3H, CH3b , JHH 6.8 Hz), 1.55 d
3
(4H, CH2CH2), 2.29 s (3H, CH311,11 ), 3.34 m (1H,
CHi-Pr,a,b
,
3JHH 6.4 Hz), 3.81 d (1H, CH2, JHH
2
3
14.5 Hz), 4.15 m (1H, CHi-Pr,a ,b , JHH 6.8, 6.4 Hz),
2
4.52 d (1H, CH2, JHH 14.5 Hz), 6.85 7.20 m
(6H, Ar).
(CHCl3) 82.57 ppm. Found, %: C 67.10;
P
1
Rf 0.57 (A), 0.56 (B), 0.59 (C), m/z 415. H NMR
H 7.68; P 7.31. C22H32N3PS. Calculated, %: C 66.82;
H 7.74; P 7.50.
spectrum (DMSO-d6), , ppm: 0.32 d (3H, CH3a, 3JHH
6.6 Hz), 0.78 d (3H, CH3a , JHH 6.6 Hz), 1.18 d
3
4,5;7,8-Dibenzo-11,11 -dimethyl-1,3,2-diazaphos-
phocane 2-oxide IX. Yield 35%, mp 172 173 C,
(3H, CH3b, JHH 6.6 Hz), 1.25 d (3H, CH3b , JHH
6.6 Hz), 2.23 s (3H, CH311), 2.27 s (3H, CH311 ), 2.86 s
(3H, NCH3), 2.89 s (3H, NCH3), 3.04 m (1H,
3
3
1
Rf 0.6 (A), m/z 272. H NMR spectrum (CDCl3),
, ppm: 2.29 s (6H, CH311,11 ), 3.93 d (1H, CH2, JHH
2
CHi-Pr,a,b), 3.71 d (1H, CH2, JHH 13.5 Hz), 3.85
2
2
14.2 Hz), 4.03 d (1H, CH2, JHH 14.2 Hz), 4.97 s
4.00 m (1H, CHi-Pr,a ,b ), 4.60 d (1H, CH2, JHH
3
(2H, NH1,3, JHH 2.2 Hz), 7.68 d (1H, JHP 614, JHH
3
3
1
13.5 Hz), 6.90 7.22 m (6H, Ar). H NMR spectrum
2.2 Hz), 6.86 7.11 (6H, Ar).
(CHCl3) 10.31 ppm.
(CDCl3), , ppm: 0.19 d (3H, CH3a, JHH 6.8 Hz),
3
P
0.85 d (3H, CH3a , JHH 6.4 Hz), 1.26 d (3H, CH3b,
3
ACKNOWLEDGMENTS
3JHH 6.4 Hz), 1.3 d (3H, CH3b , JHH 7.8 Hz), 2.27 s
3
(3H, CH311), 2.32 s (3H, CH311 ), 2.78 d (3H, NCH3,
All X-ray diffraction studies were financially sup-
ported by the Russian Foundation for Basic Research
(project no. 00-03-32578).
3JHP 10.9 Hz), 3.00 d (3H, NCH3, JHP 10.9 Hz),
3
3.09 m (1H, CHi-Pr,a,b, JHP 15.3, JHH 6.8, 6.4 Hz),
3
3
2
3.74 d (1H, CH2, JHH 14.7 Hz), 4.06 m (1H,
REFERENCES
CHi-Pr,a ,b , JHP 15.3, JHH 7.8, 6.4 Hz), 4.7 d (1H,
3
3
2
1. Zavalishina, A.I., Nurkulov, N.N., Orzhekovskaya, E.I.,
Bekker, A.R., Vasyanina, L.K., Bespalova, I.V., and
Nifant’ev, E.E., Zh. Obshch. Khim., 1995, vol. 65,
no. 5, pp. 777 781.
2. Pudovik, M.A., Ovchinnikov, V.V., Cherkasov, R.A.,
and Pudovik, A.N., Usp. Khim., 1983, vol. 52, no. 4,
pp. 640 668.
3. Nifant’ev, E.E., Zavalishina, A.I., Sorokina, S.F.,
Borisenko, A.A., Smirnova, E.I., Kurochkin, V.V.,
and Moiseeva. L.I., Zh. Obshch. Khim., 1979, vol. 49,
no. 1, pp. 64 74.
4. Nifant’ev, E.E., Zavalishina, A.I., and Smirnova, E.I.,
Phosphorus, Sulfur, Silicon, 1981, vol. 10, no. 2,
pp. 261 266.
5. Nifant’ev, E.E., Zavalishina, A.I., Dorogotovtsev, S.S.,
Orzhekovskaya, E.I., Bekker, A.R., Sirotinkin, S.P.,
and Nevskii, N.N., Dokl. Akad. Nauk SSSR, 1990,
vol. 312, no. 2, pp. 372 376.
6. Zavalishina, A.I., Dorogotovtsev, S.S., Teleshev, A.T.,
Orzhekovskaya, E.I., Bekker, A.R., and Nifant’-
ev, E.E., Zh. Obshch. Khim., 1990, vol. 60, no. 11,
pp. 2634 2636.
CH2, JHH 14.7 Hz), 6.56 7.09 m (6H, Ar).
P
(CHCl3) 69.80 ppm. Found, %: C 66.3; H 8.39;
P 7.07. C23H34N3PS. Calculated, %: C 66.5; H 8.19;
P 7.14.
2-Ethylenimino-1,3-diisopropyl-4,5;7.8-dibenzo-
11,11 -dimethyl-1,3,2-diazaphosphocane 2-sulfide
XXVII. To a solution of 0.005 mol of ethylenimine
and 0.005 mol of triethylamine in dry hexane, a so-
lution of crude phosphorochloridous diamide X in dry
benzene was slowly added with stirring at 5 10 C.
The reaction mixture was stirred at room tempera-
ture for 1.5 2 h, and triethylamine hydrochloride
was filtered off. To a solution of crude triamide XXV,
sulfur was added, the reaction mixture was stirred for
2 h, the solvent was removed, and the residue was
recrystallized from benzene. Yield 41%, mp 234
1
235 C (with decomposition). Form A. H NMR spec-
trum (CDCl3), , ppm: 1.00 d (6H, CH3a,a
,
3JHH
6.8 Hz), 1.22 d (6H, CH3b,b , JHH 6.8 Hz), 1.77 d
3
(4H, CH2CH2, JHP 17.9 Hz), 2.29 s (6H, CH311,11 ),
2
7. Cheng, C.Y., Shaw, R.A., Cameron, T.S., and
Prout, C.K., J. Chem. Soc., Chem. Commun., 1968,
no. 11, pp. 616 617.
2
3.52 d (1H, CH2, JHH 11.9 Hz), 4.37 d.d (1H, CH2,
2JHH 11.9 Hz, JHP 3.4 Hz), 4.92 m (2H, CH2i-Pr
5
,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 72 No. 2 2002

206
NIFANT’EV et al.
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