Synthesis and comparative analysis of the steric and supramolecular structures of diastereomers of 4,4-bis(trifluoromethyl)-2-(fluoroalkoxy)-6,7- benzo-1,3,2λ5- dioxaphosphepin-5-one 2-oxides

Article abstract of DOI:10.1023/B:RUGC.0000042419.00823.95

Reaction with hexafluoroacetone of 2-fluoroalkoxy-5,6-benzo-1,3,2- dioxophosphorinan-5-ones containing a chiral fluorinated exocyclic substituent on the phosphorus atom, with hexafluoroacetone leads to formation of 4,4-bis(trifluoromethyl)-6,7-benzo-1,4,2

Full text of DOI:10.1023/B:RUGC.0000042419.00823.95

Russian Journal of General Chemistry, Vol. 74, No. 6, 2004, pp. 842 859. Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 6, 2004,
pp. 915 932.
Original Russian Text Copyright 2004 by Gubaidullin, Mironov, Burnaeva, Litvinov, Dobrynin, Goryunov, Ivkova, Konovalova, Mastryukova.
Synthesis and Comparative Analysis of the Steric
and Supramolecular Structures of Diastereomers
of 4,4-Bis(trifluoromethyl)-2-(fluoroalkoxy)-6,7-benzo-1,3,2 -
5
dioxaphosphepin-5-one 2-Oxides
A. T. Gubaidullin, V. F. Mironov, L. M. Burnaeva, I. A. Litvinov, A. B. Dobrynin,
E. I. Goryunov, G. A. Ivkova, I. V. Konovalova, and T. A. Mastryukova
Arbuzov Institute of Organic and Physical Chemistry, Kazan Research Center,
Russian Academy of Sciences, Kazan, Tatarstan, Russia
Kazan State University, Kazan, Tatarstan, Russia
Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia
Received May 29, 2002
Abstract Reaction with hexafluoroacetone of 2-fluoroalkoxy-5,6-benzo-1,3,2-dioxophosphorinan-5-ones
containing a chiral fluorinated exocyclic substituent on the phosphorus atom, with hexafluoroacetone leads to
formation of 4,4-bis(trifluoromethyl)-6,7-benzo-1,4,2-dioxaphosphepines with a high regio- and stereoselec-
tivity. The configuration of all isolated individual diastereomers was established by X-ray diffraction. The
molecular and supramolecular structure of the compounds were examined in terms of the proposed model that
takes account of the revealed effect of separation of hydrophilic and lipophilic regions in the crystal.
Phosphorylated derivatives of salicylic acid (5,6-
benzo-1,3,2-dioxaphosphorinan-4-ones or salicyl
phosphites ) contain a highly reactive P O C(O)
fragment are promising reagents for preparing seven-
membered functionalyzed P-heterocycles, such as 6,7-
with hexafluoroacetone involves directly the chiral
phosphorus atom. Starting salicyl phosphites I VI
were obtained as diastereoimeric mixtures (d1 :d2
1:1) by phosphorylation of related racemic fluori-
nated carbinols with 2-chloro-5,6-benzo-1,3,2-dioxa-
benzo-1,3,2-dioxa-, 6,7-benzo-1,4,2-dioxa-, 6,7-benzo- phosphorinan-4-one. Their structure was confirmed by
1,3,2-oxaza-, and 6,7-benzo-1,4,2-oxazaphosphepines,
as well as 6,7-benzo-1,2-oxaphosphepines [1 10]
hardly available by other methods. This synthesis is
based on the regio- and stereoselective reactions
involving expansion of the starting phosphorinane
ring to phosphepine under the action of compounds
containing C=O, C=C, or C=N bonds, such as esters
spectral methods (see Experimental).
Compounds I VI, like ordinary salicyl phos-
phites studied previously [12], easily react with hexa-
fluoroacetone to give diastereomeric 4,4-bis-(trifluo-
romethyl)-6,7-benzo-1,3,2-dioxaphosphepines
XII in practically quantitative yields. The distereo-
VII
of mesoxalic, trifluoropyruvic, pyruvic, benzoylformic, meric ratio is the same as in the starting phosphites.
arylcarbonylphosphonic, and benzylidenemalonic
acids, chloral, trifluoroacetone, hexafluoroacetone
imine, and aldimines.
This fact tells in favor of a highly stereoselective
formation of the phosphate center from the P(III)
atom.
This contribution presents the results of investiga-
tion of the reaction with hexafluoroacetone of struc-
turally more complex diastereomeric salicyl phos-
phites I VI containing fluorinated alkoxyl radicals
with a chiral carbon atom as the exocyclic substituent
on phosphorus (for preliminary reports, see [11]).
1,3,2-Dioxaphosphepines VII XII are viscous
colorless oils. Their 31P {1H} NMR spectra contain
two upfield signals at
15 to 17 ppm, character-
istic of 4,4-bis(trifluoPromethyl)-6,7-benzo-1,3,2-di-
oxaphosphepines [12]. The IR spectrum of the dia-
stereomers contains one or several intense bands at
1
The use of diastereomeric derivatives I VI permits
to solve some problems concerning the stereoche-
mistry of phosphepine formation, since the reaction
1700 1730 cm , characteristic of stretching vibra-
tions of a keto group bound with a fluorinated sub-
stituent.
1070-3632/04/7406-0842 2004 MAIK Nauka/Interperiodica

SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
843
Table 1. 13C {1H} NMR spectral parameters of phosphepines VIII and XII, , ppm (J, Hz)
Atom no. Compound VIII,a , ppm (J, Hz) (acetone-d6)
Compound XII,a , ppm (J, Hz) (CDCl3)
C4
81.16 sept (sept) (29.0 29.1, FC12C4; 0, P2OC4) 83.94 sept.d (30.4, FC12C4; 8.2, P2OC4), 83.95 sept.d
(30.7, FC12C4; 8.2, P2OC4) (d1, d2)
C5
C6
C7
C8
192.34 d (br.d) (0.93 1.0, POCC5; 4.7, HC11CC5) 186.02 br.s (d2), 186.0 br.s (d1)
128.48 d (m) (1.5 1.6, P2OC7C6)
148.61 d (m) (5.4, POC7)
127.58 br.s (d1, d2)
147.75 d (8.2, POC) (d1), 147.49 d (7.4, POC) (d2)
120.60 d (d.d.d.d.d) (165.8, HC8; 7.9, HC10CC8; 121.90 d (6.6, POCC) (d2), 121.56 d (6.7, POCC) (d1)
2.5, POCC8; 1.4 1.5, HC9C8; 1.2 1.3, HC11CCC8)
C9
133.31 d (d.d.m) (165.6, HC9; 8.4, H11CC9; 1.5, 136.84 s (d1), 136.74 s (d2)
POCCC9)
C10
C11
124.73 d (d.d.m) (167.6, HC10; 5.6 6.0, HC8CC10; 127.50 s (d1), 127.47 s (d2)
1.7, POCCCC10)
129.47 br.s (d.m) (162.7 163.0, HC11; 6.0 7.0, 131.96 d (1.5, POCCC), 131.81 d (1.4, POCCC) (d1, d2)
HC9CC11)
C12, C13 122.04 q.m (q.m) (289.5, FC12; 1.1 1.2, FC13CC12) 119.63 q.m (289.0, FC) (d1, d2)
C14
75.84 q.d (d.q.d.t) (151.8, HC14; 34.2, FCC14; 4.0 73.92 br.d.m (32.3 32.7, FCC) (d2), 73.69 br.d.m (32.3
4.4, POC14; 4.0, HC17CC14)
32.7, FCC) (d1)
123.53 q.d (q.d.d) (280.6 281.0, FC; 9.8 10.0, 17.21 br.d.d (4.8 5.0, POCC; 4.8 5.0, FCCC) (d1),
POCC; 6.0 6.1, HC14C15)
16.90 br.d.m (4.8 5.0, POCC; 4.8 5.0, FCCC) (d2)
134.12 d.q (m) (2.2, POCC16; 1.0 1.2, FC15CC16) 89.89 d.m (212.4, FC; 25.7 28.5, FCC) (d1, d2)
C15
C16
a
13
17
17
15
17
18
Parenthesized are the shapes of signals in the C NMR spectra; C , 128.38 q (d.m) (167.2, HC ; 1.0 1.2, FC CCC ); C
,
20
18
19 18
17 17 18
19
19
21
19
134.61 s (d.d.d) (9.9 10.0, HC CC ; 3.9, HC
C
; 3.0, HC
C
C
); C , 130.62 s (d.d.d) (167.3, HC ; 7.9, HC CC ; 4.9,
17
19
20 19
20
20
21
21
15
21
HC CC ; 1.4 1.5, HC
17 19
C
); C , 130.78 s (d), (165.0. HC ); C , 127.06 q (d.m) (162.7, HC ; 0.9 1.0, FC CCC ).
signals appear as very complex triplets of multiplets at 110.6 and 107.8 ppm (275.0-285.0, FC) (d , d ).
1 2
b
The C
C
The structure of certain 1,3,2-dioxaphosphepines
C(CF3)2 C(O) fragment in the molecules of phos-
phepines VIII XII. The spectra were assigned on the
basis of 13C and 13C {1H} NMR experiments, as well
as our previous results for structurally related 4,4-bis-
(trifluoromethyl)-6,7-benzo-1,3,2-dioxaphosphepines
[12].
(VIII, XII) was also confirmed by the 13C NMR
spectra (Table 1). The spectra contain characteristic
downfield (
191 193 ppm) and upfield (
80
C
82 ppm) signals with expected multiplicities, pCrovid-
ing unambiguous evidence for the presence of a P O
RF
RF
R
*
*
O
+
O
F3C
CF3
O
O
O
P
P
R
+
O
O
O
CF3
CF3
O
O
I VI
A
O
RF
RF
R
*
*
O
O
+
O
P
O
P
R
O
>O
----------
CF3
CF3
CF3
CF3
^
O
O
B
VII XII
RF = CF3, R = Ph (I, VII), 3-Cl C6H4 (II, VIII), 3-MeO C6H4 (III, IX), 3-CF3 C6H4 (IV, X); RF = CF2CF2CF3, R = Ph
(V, XI); RF = cyclo-C6F11, R = Me (VI, XII).
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

844
GUBAIDULLIN et al.
1,4,2-dioxa(oxaza)phosphepin-5-ones
The reaction evidently involves initial nucleophilic
[4 11,
13]
attack of phosphorus on the carbonyl fragment of the
highly electrophilic hexafluoroacetone. The resulting
intermediate dipolar ion A containing a P C bond
containing both neutral and charged (anionic) phos-
phorus. Therefore, in this work we considered it ex-
pedient not only to discuss details of the steric struc-
ture of compounds VIII XII, but also to compare
them with our previous data for structures XIII
XXVII.
undergoes P+ C O
P+ O C rearrangement to
give dipolar ion B which stabilizes via intramolecular
nucleophilic substitution at the carbon atom of the
endocyclic carbonyl group.
First of all note that no one of our studied mole-
cules had a chair conformation of the seven-mem-
bered heterocycle, even though gas-phase calculations
[6, 14] show that this conformation is close in sta-
bility to the unsymmetrical distorted bath or twist-
bath conformations realized in most of the above
molecules (in crystal). A specific feature of the mo-
lecules in hand is a planar C5C6C7O1 four-atomic
fragment. The remaining P4, C3, and X4 (X=O, N)
atoms locate on the one side of this plane, deviating
from it by different distances (in the bath conforma-
tion). The presence of this planar fragment in many
aspects predetermines the bath conformation of 1,4,2-
dioxa- and 1,4,2-oxazaphosphepines XX XXVI. A
specific feature of 1,3,2-dioxa- and 1,3,2-oxazaphos-
phepines XIII XIX is that their heterorings can exist
in three different conformations: distorted unsym-
metrical bath, unsymmetrical twist-bath (with a
C4C5C6C7O1 five-atomic fragment and P2 and X3
deviating by different distances to one side from it),
and unsymmetrical twist (with a planar C5C6C7O1
four-atomic fragment and P2 and X3 deviating to one
side from it and C4, to the opposite side; the devia-
tion of X3 from the base plane is insignificant).
All the prepared isomeric phosphepines VII XII
partially crystallized when kept in a mixture of ether
and methylene chloride. The isolated crystals were
individual diastereomers. Their purity was controlled
by 31P and 13C NMR (compound VIII, Table 1)
spectroscopy. Crystallization from acetone almost
always provided single crystals suitable for X-ray
diffraction analysis (compounds VIII XII).
By now we have accumulated an abundant experi-
mental evidence for the steric structure of unsym-
metrical functional derivatives of seven-membered
heterocycles, such as 6,7-benzo-1,3,2- and 6,7-benzo-
O
O
1
O
2
P
O
R1
7
P
R
NH
3 O
6
5
4
R2
CF3
R3
CF3
O
O
XIII XVII
XVIII, XIX
R1 = NEt2, R2 = Ph, R3 = COOEt (XIII); R1 = O Et3NH+,
R2 = R3 = CF3 (XIV); R1 = OEt, R2 = CF3, R3 = COOMe
(XV); R1 = OH, R2 = Ph, R3 = P(O)(OEt)2 (XVI); R = OH,
R2 = 4-ClC6H4, R3 = P(O)(OMe)2 (XVII); R = NEt2
(XVIII), Ph (XIX).
5
Evidently, 6,7-benzo-1,3,2 -dioxaphosphepin-5-one
5
2-oxides and 6,7-benzo-1,3,2 -oxazaphosphepin-5-
one 2-oxides are much more conformationally labile
than 6,7-benzo-1,4,2 5-dioxaphosphepin-5-one
O
O
1
O
5
2
2-oxides and 6,7-benzo-1,4,2 -oxazaphosphepin-5-
O
R1
P
P
R
one 2-oxides.
R2
R3
7
6
3
Ph
4
5
O
N
The conformational behavior of substituents on
phosphorus in these unsymmetrical heterocycles is
largely determined by the general anomeric effect [15],
but there are some exceptions. Hence, the diethyl-
amino or ethoxy groups on phosphorus in crystalline
1,3,2-dioxaphosphepines XIII and XV have opposite
orientations (pseudoaxial diethylamino group in XIII
and pseudoequatorial ethoxy group in XV), what
disagrees with the concept of the anomeric effect [15].
At the same time, the example of these two structures
allows no prognostic conclusions as to the preferred
orientation of substituents on the phosphorus atom. In
this connection the investigation of five new 6,7-
benzo-1,3,2-dioxaphosphepine derivatives VIII XII
that essentially complement the range of previously
studied structures would provide further information
for solving this problem.
NMe2
O
O
XX XXII
XXIII
R1 = OCH2CF2CHF2, R2 = CF3, R3 = Me (XX); R1 = Ph,
R2 = H, R3 = CCl3 (XXI); R1 = OMe, R2 = H, R3 = CCl2
(XXII); R = OC6F5 (XXIII).
O
O
P
R
CF3
CF3
N
H
O
XXIV XXVI
R = OMe (XXIV), OCH2CF2CHF2 (XXV), OEt2NH2+
(XXVI).
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SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
845
F223
C22
F222
C5
C6
F211
F133
F221
F213
F202
F211
F132
O2
F201
C13
C21
F212
O3
C12
F131
C15
C20
F203
F212
C19
C18
O5
C14
C20
O16
C4
P2
O4
O3
C21
F213
C4
C16
C17
O2
C15
C19
O1
C14
C13
C6
O5
O1
C16
Cl1
C5
C11
O4
C11
C10
C18
C17
C7
C8
C12
C7
C8
F131
C9
F132
C10
F133
C9
Fig. 2. Molecular geometry of phosphepine IX in crystal
and numbering scheme.
Fig. 1. Molecular geometry of phosphepine VIII in
crystal and numbering scheme.
C9
F132
F133
C19
C18
C10
C7
F213
F222
C11
C13
C8
C12
O2
C20
C21
C18
F211
C19
C15
C16
C6
C21
O5
C17
O4
P1
O3
C4
O1
P2
O4
C14
C16
C12
C22
O1
F223
O5
C5
F12
C23
C4
C17
F1
C13
F4
F3
C15
C5
C6
O3
F8
O2
C7
C22
F9
C8
C9
C14
F202
F203
F11
F10
F201
F2
F13
C11
C10
F5
F6
F7
Fig. 3. Molecular geometry of phosphepine X in crystal
Fig. 4. Molecular geometry of phosphepine XI in crystal
and numbering scheme.
and numbering scheme.
The heteroring conformation in VIII XII
(Figs. 1 5) relate to the first type of conformations,
i.e. a distorted unsymmetrical bath with a planar
C5C6C7O1 fragment and P2, O3, and C4 locating on
one side of this plane at different distances from it
(Table 2). The phosphoryl group in these compounds
is pseudoequatorial and the substituted alkoxy groups
are pseudoaxial. Like in our previous works [4 11,
13], to describe location of substituents on the phos-
phorus atom in such heterorings we use the terms
Table 2. Distances of selected atoms ( ) from the planar fragment O1C7C6C5 in molecules VIII XII (parenthesized are
rms deviations).
Atom
VIII
IX
X
XI
XII
P2
1.240(7)
1.72(1)
0.85(2)
0.83(2)
0.19(2)
2.03(3)
1.2878(9)
1.741(2)
0.973(3)
0.616(3)
5.799(3)
7.009(4)
1.2662(9)
1.797(5 )
1.058(3)
0.799(3)
2.144(4)
0.406(4)
1.2295(6)
1.746(2)
0.989(2)
0.642(2)
8.369(3)
2.077(3)
1.2693(9)
1.661(2)
0.834(4)
0.598(5)
1.859(4)
0.102(4)
O3
C4
O5
C20 (C22)
C21
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

846
GUBAIDULLIN et al.
Table 3. Selected torsion angles (deg) in molecules VIII XII and puckering amplitudes of their seven-membered
heterorings (Q,
)
Angle
VIII
IX
X
XI
XII
O4P2O1C7
O2P2O1C7
O3P2O1C7
O1P2O3C4
O2P2O3C4
O4P2O3C4
P2O1C7C6
P2O1C7C8
P2O3C4C5
O3C4C5C6
O3C4C5O5
C4C5C6C7
O5C5C6C11
O5C5C6C7
C5C6C7O1
C5C6C7C8
C11C6C7O1
C11C6C7C8
O1P2O4C12
O2P2O4C12
O3P2O4C12
P2O4C12C13
P2O4C12C14
Qa
55(2)
175(2)
46(2)
44(2)
80(2)
153(2)
67(3)
110(2)
65(2)
5.25(3)
176(2)
52(4)
36(3)
129(3)
6(4)
177(3)
172(2)
11(4)
112(2)
14(2)
57.5(2)
173.2(2)
45.8(2)
45.1(2)
79.0(2)
156.2(2)
74.2(3)
112.3(2)
65.0(2)
4.4(3)
179.2(2)
43.4(3)
35.1(4)
142.1(3)
4.7(4)
178.0(2)
172.4(2)
0.8(4)
111.7(2)
15.2(2)
140.9(2)
104.7(2)
132.3(2)
56.3(3)
174.9(2)
46.2(3)
43.3(3)
82.1(3)
153.0(3)
72.8(4)
112.0(3)
59.4(4)
12.9(5)
168.9(3)
52.5(5)
45.4(5)
129.4(4)
0.3(5)
175.1(4)
174.4(3)
0.5(6)
111.3(3)
15.1(3)
141.0(3)
130.6(3)
106.9(3)
53.1(2)
178.4(2)
50.8(2)
39.3(3)
85.9(3)
147.0(3)
74.7(3)
110.2(3)
63.0(4)
3.9(4)
176.3(3)
44.9(5)
32.3(5)
143.3(4)
1.8(5)
176.6(3)
173.8(3)
1.1(5)
131.3(2)
5.1(3)
121.9(2)
109.7(3)
126.0(2)
53.1(3)
177.7(3)
51.3(3)
38.5(3)
86.4(3)
146.5(3)
70.4(4)
116.2(3)
67.9(4)
5.8(5)
171.8(4)
39.5(6)
31.5(6)
143.1(5)
1.1(6)
171.8(4)
175.5(3)
2.7(6)
152.9(3)
26.2(3)
99.9(3)
76.5(3)
159.1(2)
142(2)
136(2)
108(2)
0.883(21)
0.864(2)
0.894(3)
0.867(3)
0.843(3)
a
Q is the Cremer Pople heteroring puckering parameter [16].
pseudoequatorial and pseudoaxial, since the un-
symmetrical conformation of the ring leads to a situa-
tion when one and the same substituent has different
conformations along endocyclic P O bonds determi-
ning its position: gauche from one side (what cor-
responds to the axial position) and transoid from the
other (what corresponds to the equatorial position).
The principal torsion angles in the heterorings of
molecules VIII XII and angles describing substituent
positions in them are listed in Table 3.
We also examined heteroring puckering in these
molecules according to Cremer and Pople [16]. As
shown in Table 3, the torsion angles in the heterorings
of compounds VIII XII are no larger than 10 , and
the puckering amplitudes also do not vary significant-
ly. Nevertheless, it can be noted that the strongest
heteroring puckering is characteristic of molecules
VIII and X, and the most flattened heteroring is ob-
served in molecule XII with the bulky perfluorocy-
clohexyl substituent. Hence, it can be proposed that
bulky substituents on phosphorus lead to heteroring
flattening. Since the heteroring conformations in pre-
viously studied molecules XIII and XV differ from
those established for structures VIII XII, we do not
compared their puckering parameters. Therewith, the
puckering amplitude of the heteroring in XV is
slightly larger [1.033(3) ] than in VIII XII [average
0.923(3) ]. Note that the C4 atom in XIII and XV
bears ethoxy- and methoxycarbonyl substituents.
Consequently, the flattened unsymmetrical twist-bath
F201
C20
F203
F211
F192
F202
F213
F191
F182
C14
C18
C21
P2
O4
C19
O3
F212
C4
F172
F151
F181
F148
F152
O1
C7
O5
C5
C6
C17
F171
C15
C16
C8
C9
F162 F161
C11
C10
Fig. 5. Molecular geometry of phosphepine XII in
crystal and numbering scheme.
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SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
847
Table 4. Principal bond lengths d ( ) in molecules VIII XII and XV
Bond
VIII
IX
X
XI
XII
XVa
P2 O1
P2 O2
P2 O3
P2 O4
O1 C7
O3 C4
O4 C12
O5 C5
C4 C5
C5 C6
C6 C7
1.55(2)
1.45(1)
1.59(2)
1.58(2)
1.45(3)
1.48(3)
1.43(3)
1.29(3)
1.49(4)
1.45(3)
1.34(3)
1.566(2)
1.443(1)
1.592(1)
1.563(2)
1.402(2)
1.414(3)
1.466(2)
1.206(3)
1.564(3)
1.478(4)
1.390(3)
1.564(3)
1.438(2)
1.586(2)
1.560(2)
1.430(4)
1.427(4)
1.449(4)
1.220(5)
1.548(6)
1.487(5)
1.372(5)
1.568(3)
1.440(2)
1.584(2)
1.556(2)
1.414(3)
1.417(3)
1.464(3)
1.207(4)
1.574(5)
1.475(5)
1.370(4)
1.567(2)
1.448(3)
1.600(3)
1.549(2)
1.420(4)
1.408(5)
1.467(4)
1.185(6)
1.573(5)
1.486(4)
1.361(6)
1.582(3)
1.451(3)
1.585(3)
1.536(3)
1.408(4)
1.425(5)
1.456(7)
1.210(4)
1.554(6)
1.487(5)
1.402(6)
a
Average values for two independent molecules in the crystal are listed [10]
*
conformation of these heterorings is determined by
the substituents on the C4 atom. The fact that the
heteroring conformation in six of the ten 1,3,2-dioxa-
phosphepines studied is distorted unsymmetrical bath,
which is also true of the seven 1,4,2-dioxa- and oxa-
zaphosphepines XX XXVI, gives us grounds to state
that this conformation is most characteristic of 6,7-
benzo-1,3,2- and 6,7-benzo-1,4,2-oxaheterophos-
phepines.
molecules (Table 3). In this conformation, n
inter-
action of lone electron pairs of the exocyclic oxygen
atom with antibonding orbitals of one or two endo-
cyclic O P bonds (inverse anomeric effect) is pos-
sible. In molecule XV, the ethoxy group on phospho-
*
rus is pseudoequatorial and renders impossible n
interaction of lone electron pairs of O1 with the
exocyclic P O bond.
The above reasoning generally agrees with the
trends in bond lengths and angles at the phosphorus
atom in molecules VIII XII that have an axial alkoxy
substituent, as well as in molecule XV that has an
equatorial ethoxy group (Table 4 and 5). Regretfully,
we have to exclude from this comparison structure
VIII whose geometric parameters were determined
with large experimental errors. As follows from
Table 4, the endocyclic O1 P2 bonds in VIII XII are
shorter than in XV, while the endocyclic O4 P bonds
are longer. This difference in bond lengths can be
explained by the anomeric effect in the former mole-
cules and by the inverse anomeric effect in the latter.
The same stereoelectronic effects may cause the dif-
ference in the endocyclic O1P2O3 bond angles. In
molecules VIII XII, these angles are considerably
larger [103.8(1) 104.7(1) ] than in molecule XV [on
average, 102.7(1) ] (Table 5). Hence, the analysis of
the geometric parameters of molecules VIII XII
shows that the observed trends in bond lengths and
angles at the phosphorus atom are explainable in
terms of the general anomeric effect, and that the
model of hyperconjugation stereoelectronic interaction
is feasible for interpreting the structure of such un-
symmetrical heterocyclic systems.
As mentioned above, the phosphoryl group in
VIII XII occupies the pseudoequatorial position, and
the alkoxy substituent is pseudoaxial. This complies
with the anomeric effect and is best presented gra-
phically by means of Newman projections. Below we
give the Newman projects along the O P bonds in
molecule XII; in the other molecules, the general
view of the projections is the same.
P2 O1
O2
P2 O3
O2
P2 O4
C12
C4
O2
O1
O3
O4
C7
O4
O1
O3
It is readily seen that the anomeric oxygen atom in
these molecules has the usual chess conformation
along the O1 P2 bond. This conformation favors
hyperconjugation interactions between lone electron
pairs of O1 and nonbonding orbitals of the O3 P and
*
O4 P bonds (n
interaction). At the same time, the
conformation along the O3 P bond is only favorable
for interaction of its lone electron pairs with the
antibonding orbital of the P=O2
bond. Along the
exocyclic P O4 bond, an eclipsed conformation with
the P=O bond cis to O4 P is formed, that is sym-
metrical in XI and slightly unsymmetrical in the other
The geometry of substituents in molecules VIII
XII is usual. In phosphepines VIII XI, an eclipsed
conformation with the P2 O4 bond shielding C12 H is
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

848
GUBAIDULLIN et al.
Table 5. Principal bond angles
(deg) in molecules VIII XII and XV
Angle
VIII
IX
X
XI
XII
O1P2O2
O1P2O3
O1P2O4
O2P2O3
O2P2O4
O3P2O4
P2O1C7
P2O3C4
P2O4C12
O3C4C5
O5C5C4
O5C5C6
C4C5C6
C5C6C7
C5C6C11
C7C6C11
O1C7C6
O1C7C8
111(1)
104.1(9)
107.3(8)
118.3(9)
117.8(9)
96.6(8)
125(2)
127(1)
121(1)
110(2)
111(2)
122(3)
127(2)
124(2)
118(2)
116(2)
117(2)
117(2)
111.98(9)
103.81(8)
108.3(1)
117.2(1)
116.17(9)
97.86(8)
122.3(1)
128.4(1)
121.1(1)
114.4(2)
116.2(2)
122.3(2)
121.3(2)
124.7(2)
117.9(2)
117.4(2)
119.8(2)
117.9(2)
112.2(2)
104.7(1)
107.0(1)
117.7(1)
116.3(1)
97.2(1)
121.9(2)
129.0(2)
123.3(2)
114.1(3)
116.8(3)
122.2(4)
120.9(3)
123.8(3)
116.8(3)
119.2(3)
118.7(3)
117.5(3)
113.2(1)
103.6(1)
104.6(1)
116.9(1)
117.1(1)
99.6(1)
120.5(2)
130.5(2)
123.8(2)
113.8(3)
115.6(3)
122.4(3)
121.6(3)
124.3(3)
117.7(3)
117.9(3)
117.9(3)
117.5(2)
113.3(1)
103.8(1)
104.7(1)
115.8(1)
117.4(2)
99.9(1)
121.5(2)
129.9(2)
123.8(2)
113.2(2)
116.0(3)
122.2(4)
121.7(4)
126.4(4)
115.6(4)
117.7(3)
120.8(3)
116.2(4)
realized along the O4 C12 bond. Therewith, the bulky
fluorinated substituents are anticlinal with respect to
the P2 O4 bond, thus best minimizing steric contacts
in the molecule. Compound XII is an outlier of this
series. It features a chess conformation along the P2
O4 bond with transoid location of the P2 O4 and C12
C14 bonds. In such a conformation, the heteroring and
bulky perfluorocyclohexyl substutuents are remote
from each other as much as possible. Hence, the
conformations along exocyclic P O bonds in phos-
phepines VIII XII are evidently controlled by steric
factors.
Having a sufficiently large set of similar structures,
we could analyze and generalize the peculiarities of
intra- and intermolecular interactions in compounds
VIII XII as a function of the type of the exocyclic
substituent on phosphorus. The molecules have iden-
tical heterocyclic fragments and differ only in the
nature of radicals on the chiral -carbon atom (C12)
of the exocyclic alkoxy substituent. Nevertheless, as
we showed above, the nature of the radical exerts a
certain effect on the heteroring conformation (in
particular, this is reflected in the varied heteroring
puckering parameter).
C17
Cl1
C15
C16
C14
C18
C19
Note that compounds VIII XII all form crystals
free of solvent molecules. Inspite of the absence of
classical hydrogen bonds, these crystals contain a
developed system of intermolecular interactions of
H19
C8
F131
O4
H12
F133
C9
other types, in detail C H O , C H
, and
.
C10
C6
Moreover, many short contacts involving fluorine
atoms are observed, which, too, can considerably
affect the crystal packing [17].
C7
C5
O2
C11
O1
3P2
F213
O
C4
C20
C21
F201
F202
O5
The formation of hydrogen-bonded dimers is cha-
racteristic of all the compounds under study. Hence,
the formation of a couple of bifurcate C H O hydro-
gen bonds between O2 and the H12 and H19 protons of
two molecules VIII related to each other by a sym-
metry center gives rise to dimer formation (Fig. 6).
211
F
212
F
F203
Fig. 6. Hydrogen-bonded dimer of molecule VIII in
crystal. Hydrogen bonds are shown by dashed lines.
The C12 H12 O2 (1
x, y, z) and C19 H19 O2
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SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
849
Fig. 8. Crystal packing of molecules VIII and formation
Fig. 7. -Dimer of molecules VIII in crystal. Hydrogen
atoms are not shown.
of a bilayer structure. Hydrogen bonds are shown by
dashed lines.
interaction parameters in the crystal of compound
cules enter stacking interaction with the phenyl rings
of molecules from neighboring stacks) (Fig. 8).
VIII are the following: C12 H12 0.99 , H12 O2
2.37 , C12 H12 O2 angle 159 C and C19 H19
0.99 , H19 O2 2.57 , C19 H19 O2 angle 144 ,
respectively.
Here we deal with an effect of localization of
hydrophilic and hydrophobic regions in the crystal,
resulting in formation of lamellar structures (layers
comprising cyclic fragments and layers comprising
organofluorine fragments, alternating along the 0x
axis). Such location facilitates multiple F F (average
interatomic distance 3.07 ) and Cl F contacts. All
the above-mentioned contacts lead to a tight crystal
packing (packing factor 68.7%, specific gravity
1.77 g/cm3) containing no free space. Hence, the
formation of supramolecular lamellar motifs in the
In addition, O2 forms an intramolecular contact
with H12 (H12 O2 2.52 , C12 H12 O2 110 ). Thus
O2 takes part in a trifurcate hydrogen bond. The
planes of the phenyl substituent and condensed benzene
fragment are almost parallel to each other, the dihedral
angle between them is 10.9 , and the distance between
the ring centers is 5.65 . Despite the insignificant
overlap of these planes the PLATON program [18]
we used to analyze intra- and intermolecular interac-
tions shows the presence of intramolecular
interactions between them. Note that the mutual loca-
tion of the phehyl and benzo fragments in the molecule
occurs to be favorable for their intermolecular contact
with the -systems of the phenyl and benzo fragments
of a neighboring molecule related to the former by a
symmetry center ( x, y, z), thus leading to forma-
tion of a peculiar molecular -dimer (Fig. 8). Param-
eters of these contacts are identical, the dihedral angle
between the ring planes is 10.9 , and the distance
between the ring centers is 3.82
.
Therewith, the phenyl substituents of molecules
related as ( x, 1 y, z) form a short contact (dihedral
angle 0 , distance between the ring centers 3.71 ),
giving rise to the stacking effect between them. These
interactions lead to formation of a dimeric layer of
molecules, located parallel to the 0xy crystallographic
plane (since the phenyl substituents of dimeric mole-
Fig. 9. Hydrogen-bonded dimer of molecules IX in
crystal. Hydrogen bonds are shown by dotted lines.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

850
GUBAIDULLIN et al.
crystal of compound VIII is determined by various
, C H O, and C H F interactions that bind
molecules along two mutually perpendicular direc-
tions. Note that the configuration of the chiral P2 and
C12 atoms in VIII is the same (SP, SC or RP, RC),
because this product is racemic and crystallizes in a
centrosymmetric group.
Substitution of chlorine in the phenyl fragment by
a methoxy group in compound IX completely changes
the molecular conformation, while not significantly
affecting the heteroring conformation. First of all note
that such substitution leads to crystallization of the
other diastereomer (the configurations of P2 and C12
do not coincide) in which the substituents on O4 are
rotated so that the benzo fragment is practically
perpendicular to the phenyl plane [dihedral angle
86.1 ] (Fig. 10). Such conformation leads to a looser
crystal packing (packing factor 67.7%, specific gravity
1.65 g/cm3), even though no free space available for
solvents appears. As a result, molecular dimers are
formed exclusively by two C H O bonds between
H12 and O2 (1 x, 1 y, 2 z), having the following
parameters: H12 O2 2.33(2) , C12 H12 O2 angle
151.2(2) (H19 is not involved in hydrogen bonding).
The same atoms form an intramolecular H12 O2
contact [H12 O2 distance 2.44(2) , C12 H12 O2
angle 116(1) ].
Fig. 10.
Interactions of molecules in the crystal of
compound IX. Hydrogen atoms are not shown.
Each of the molecules in a dimer takes part in two
contacts in mutually perpendicular directions
(Fig. 10). Molecular dimers form chains running the
0bc diagonal, by means of
-
interactions of the
benzo fragments of neighboring molecules related as
(1 x, y, 1 z) (distance between the ring centers
3.71 , dihedral angle 0 ).
Fig. 11. Crystal packing of molecules IX and formation
of a bilayer structure.
The involvement of phenyl groups in mutual
contacts with the corresponding substituents of
molecules related to the initial one as ( x, y, 2 z)
and ( x, 1 y, 2 z) (the distances between the rings
centers are 5.31 and 5.36 , respectively, the dihed-
ral angles are 0 ) leads to formation of a dimeric layer
of hydrogen-bonded molecules. These layers are
parallel to the main diagonal of the cell (0bc) and
separated from one another by lipophilic regions
comprising organofluorine fragments (Fig. 11).
Such a lamellar crystal packing of molecules IX,
too, gives rise to multiple short contacts between
fluorine atoms and proves to be sufficiently tight for
the crystal to contain no free space.
Since the crystals of compounds X and VIII are
isostructural, the molecular conformations in them are
the same. But the substitution of the methoxy group
in the phenyl substituent by trifluoromethyl radically
Fig. 12. Hydrogen-bonded dimer of molecules X in
crystal. Hydrogen bonds are shown by dashed lines.
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SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
changes the type of supramolecular structure and
851
crystal packing. Therewith, the packing factor (67%)
decreases, but the calculated specific gravity
(1.73 g/cm3) of the crystal of compound X increases.
Like in the above-described system of hydrogen
bonds in the crystal of compound VIII, the phos-
phoryl oxygen atom O2 in X is involved in a trifurcate
hydrogen bond with the H12 and H19 protons of a
molecule related to the initial one as (2 x, y, z)
and with the own H12 proton to form a hydrogen-
bonded dimer (Fig. 12).
Note also that the substitution of the chlorine atom
in the phenyl substituent of compound VIII by a tri-
fluoromethyl group leads to a considerable weakening
of intermolecular contacts in the crystal of compound
X. The distances H12 O2 and H19 O2 vary from
2.37(2)
2.60(2)
and 2.57(2)
and 2.71(4)
in the former crystal to
in the latter. At the same
Fig. 13. Cylindrical supramolecular fragments in the
crystal of compound X. Fluorine atoms are shadowed.
time, the parameters of intramolecular interactions
remain almost unchanged.
phobic regions, the supramolecular fragments can be
considered as cylinders located along the 0a axis, with
an inner hydrophilic and an outer hydrophobic regions
(formed largely by fluorine atoms) (Fig. 14), unlike
the lamellar crystal structure of VIII. As follows from
the calculated degrees of hydrophilicity of the mole-
cular fragments of compound X, the outer part of the
condensed benzene ring, too, possesses hydrophobic
properties. On the whole the crystal packing in this
case can be regarded as parallel stacking of
cylindrical fragments. Therewith, joining the hydro-
Analysis of the supramolecular structure of com-
pound
X
reveals existence of supramolecular
isomerism in its crystals [19]. From the viewpoint of
intermolecular interactions [2], the supramolecular
structure can be considered as a bilayer that comprises
molecular dimers bound with each other in two
mutually perpendicular directions by
contacts of
aromatic rings and located in the 0ab plane. But from
the viewpoint of separation of hydrophilic and hydro-
C18
C19
C20
C21
F152
F141
C14
F142
C17
C16
C15
F153
C12
C13
F151
O4
F131
O2
F132
H8
O3
C8
C9
C10
C11
P2
O1
F223
F222
F221
F232
C7
C5
F231
F223
O5
Fig. 14. Molecular dimer in the crystal of compound XI. Hydrogen bonds are shown by dashed lines.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

852
GUBAIDULLIN et al.
H12
H8
O1
Fig. 15. Infinite chain of hydrogen-bonded molecules
in the crystal of compound XI. Fluorine and hydrogen
atoms of the benzo fragment are not shown.
Fig. 16. Bilayer structure in the crystal of phosphepine
XI. Fluorine atoms are shadowed.
phobic outer shells of the cylinders gives rise to
multiple F F and F H contacts.
contacts with molecules of neighboring parallel chains
to form tilted stacks of aromatic fragments with the
shortest interplanar spacing of 3.66 and the dihedral
angle of 0 . Under these conditions, the stacking
effect takes place and formation of a two-dimensional
bilayer supramolecular structure (Fig. 16) with in-
layer localization of the fluorine-containing fragments.
In terms of the model considering intermolecular
interactions of only one type or our model considering
separation of hydrophilic and hydrophobic regions in
crystal, the most preferable in this case must be again
a cylindrical supramolecular fragment with the inner
part comprising hydrogen-bonded heterocyclic
fragments and the outer part comprising the hydro-
phobic fluorine-containing radicals. Evidence for such
a supramolecular block comes at least for the cal-
culated degree of hydrophilicity of this molecule.
The crystals of XI are also isostructural to the
crystals of VIII and X, the conformation of molecule
XI is the same as of the above-mentioned compounds.
Note that substitution of hexafluoropropyl trifluoro-
methyl on the chiral carbon atom C12 increases the
calculated specific gravity (1.79 g/cm3) and packing
factor (67.9%). The dihedral angle between the phenyl
and benzo ring planes is 0 , that is these planes are
parallel. Such a mutual location is stabilized by an
intramolecular hydrogen bond between O4 and H21
[H21 O4 distance 2.60(3)
, C21 H21 O4 angle
152(7) ]. In the crystal of compound XI, centrosym-
metric dimers are also formed by C H O interactions
(Fig. 14), but the significant difference is that each
molecule forms two dimers. One of them is formed by
contacts between the H8 and O1 (1 x, y, z) atoms
of neighboring molecules [H8 O1 distance 2.59(3)
C8 H8 O1 angle 156(3) ]. At the same time, pair
,
In the crystal of perfluorocyclohexyl derivative XII,
maximum calculated specific gravity (1.95 g/cm3) and
packing factor (69%) are achieved. The same dia-
stereomer as in most other cases (SPSC) crystallizes. At
the same time, the crystal of XII is not isostructural
to the crystals of VIII XI. The mean plane of the
cyclohexane ring occurs to be almost perpendicular to
the plane of the benzo fragment [dihedral angle
77.0(2) ], like in a single analogous case of compound
IX. The crystal of compound XII contains molecular
interaction is observed between the corresponding
phenyl and condensed benzo fragments of the same
molecules. The distance between the ring centers is
3.88 , and the dihedral angle is 3.58(2) . Hence, this
molecular dimer is formed both by hydrogen bonding
and by interaction of aromatic fragments of the
molecules. In their turn, the molecules of the dimer
both form with neighboring molecules located along
the 0a crystal axis a pair of identical contacts between
contacts of various types (C H O, C H
,
,
H12 and O2 [H12 O2 distance 2.76 (3) , C12 H12
O2 angle 172.0(5) ], thus forming an infinite chain of
hydrogen-bonded molecules (Fig. 15).
F F and F H). Therewith, only two C H O hydro-
gen bonds were found: an intramolecular contact
H12 O2 and an intermolecular hydrogen bond H12
The molecules in these chains take part in
O2 (1 x, 1 y, z) [H12 O2 distance 2.40(3)
,
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SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
853
F213
F202
C20
C21
O5
C5
F211
F201
C4
F203
O2
O3
C11
C6
C10
C9
P2
7 O1
O4
C
C13
C8
C12
C14
F151
F152
F148
C15
F192
F182
F161
F181
F171
Fig. 17. Molecular dimer in the crystal of compound
XII. Hydrogen bonds are shown by dashed lines.
Fig. 18. Formation of a molecular chain in the crystal of
compound XII.
C12 H12 O2 angle 150(3) ], that lead to formation of
a molecular dimer (Fig. 17).
clusions. The compounds all crystallize in triclinic
centrosymmetric cells with fairly close parameters,
but only three crystals among the five considered are
isostructural. In most compounds under study, the
SPSC (RPRC) diastereomer with coplanar aromatic frag-
ments crystallizes. Evidently, coplanarity of the
aromatic fragments depends on the size of the sub-
stituent in the phenyl ring.
The molecular dimers are bound with each other
by
interaction of the condensed benzene rings to
form a chain of dimers along the 0c axis (Fig. 18).
The molecular chains are located one above another
in such a way that the parallel packing of such supra-
molecular fragments gives rise to the stacking effect,
viz.
interactions between the condensed
Intermolecular contacts in the crystals of all the
compounds studied result in initial formation of mo-
lecular dimers. Evidently, it is a molecular dimer
benzo substituent of each molecule and the benzo
fragments of two other molecules related to the initial
one by a symmetry center and translations by +1 and
1 along the 0a axis (distance between the ring
centers 3.66 and 4.05 , dihedral angle 0 ). The
shortest interplanar spacing is 3.51 . Thus a two-
dimensional lamellar structure is formed. The inter-
molecular interactions in two directions inside the
layer differ in nature. Along the 0c axis, C H O and
contacts take place, while along the 0a axis,
contacts exclusively. Allowance for only one of the
revealed types of interactions, for example, contacts
between aromatic systems, would result in a cylin-
drical supramolecular structure.
Here, again, we observe localization of hydrophilic
and hydrophobic regions in the crystal, because the
above-described layers alternate along the 0b axis
with layers comprising fluorine-containing substi-
tuents (Fig. 19).
The above analysis of the structure of the com-
pounds and their crystal packing allows certain con-
Fig. 19. Crystal packing of molecules XII. Hydrogen
atoms are not shown.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

854
GUBAIDULLIN et al.
that is a real supramolecular synthon [20] for this type
of compounds. But there are different ways of binding
of the dimers into supramolecular motifs: C H O
contacts exclusively, combination of C H O and
clearer understanding of the existence of supramole-
cular isomerism.
A possible reason for the amphiphilicity of mole-
cules in crystals is their tendency for an energy
minimum and, as a result, to leveling of the chemical
potential inside the crystal, which is associated with
the tendency for the largest possible interface between
regions of different types. Therewith, however,
constraints imposed by the symmetry of the crystals
formed must be followed. Probably, lamellar struc-
tures in cubic crystals are impossible to form not
disturbing the symmetry inherent in to this syngony.
Note that weak interactions in the crystals of these
compounds are not the main motive force of crystal-
lization. Despite the fact that a number of compounds
of the series in hand are isostructural, i.e. have similar
crystal packings, the system of intermolecular contacts
in the crystals can considerably vary, thus leading to
different supramolecular structures. However, the
separation of regions with largely hydrophilic and
largely lipophilic properties is characteristic of all the
compounds.
contacts, or
contacts of two types. Contacts like
F F and F H are observed in all the compounds.
Their variability and specific features need separate
consideration which is proposed to be made later with
a broader range of compounds of this class.
The combined effect of intermolecular contacts
gives rise to lamellar and cylindrical supramolecular
structures. The isostructural crystals feature the effect
of supramolecular isomerism: Depending on the
chosen individual type of intermolecular contacts,
supramolecular fragments of different topologies can
be recognized in the crystals. Therewith, localization
of regions containing fluorine-substituted fragments
takes place. In view of the fact that the phosphorus-
containing heterocyclic fragment is identical in all the
compounds under study and all distinctions relate to
the type of substituents on the O4 atom, we can state
that increasing number of fluorine atoms in a mole-
cule (with the associated increase in the molecular
weight) leads to increase in the specific gravity and
the packing factor of its crystal.
It is known from published data that four-coordi-
nate phosporus derivatives containing residues of
fluorinated secondary and tertiary alkanols structurally
similar to those studied in the present work undergo a
solid-phase diastereomeric transformation on pro-
longed handling [25]. We observed no such trans-
formation in phosphepines VII XII handled for
2 years at 20 25 C in sealed ampules.
Localization of fluorine-substituted fragments in
the crystals is a specific case of the general pheno-
menon we revealed and described previously [21], that
is separation of hydrophilic and hydrophobic regions
in crystals. These regions not necessarily include the
whole molecules of a compound or, for example,
solvation molecules, and are formed by molecular
fragments that possess largely hydrophilic or lipo-
philic properties. Our calculations of the degrees of
hydrophilicity and hydrophobicity of the molecular
fragments of the compounds in study and compounds
of other classes, as well as comparison of the resulting
values with the character of crystal packing provides
unambiguous evidence for a more general character
of this phenomenon. The associates formed as a result
of such localization, which can be regarded as supra-
EXPERIMENTAL
The IR spectra were recorded on a Specord IR-75
spectrometer in thin layer or suspensions in mineral
oil between KBr plates. The NMR spectra were
recorded on Bruker MSL-400 (13C, 100.6 MHz; 31P,
162 MHz), Varian Unity-300 (1H, 300 MHz, 19F,
282 MHz; 31P, 121.4 MHz), and Bruker WP-200SY
(19F {1H}, 188.3 MHz) instruments.
Single-crystal X-ray diffraction analysis of
molecular structure, can assume the form of cylinders, compounds VIII XII were carried out on an Enraft-
layers and spheres similar to those observed in super
crystals [22]. In particular, the crystal structures in
study comprise cylindrical fragments with a hydro-
philic inner and a hydrophobic outer (formed mainly
by fluorine atoms) regions. The crystal packing in this
case can be regarded as parallel packing of such
cylindrical fragments, that joins the hydrophobic outer
shells of the cylinders. Sometimes such supramole-
cular structures coincide with structural fragments
formed by hydrogen bonding, but, evidently, this is
not a general rule. Considering this fact provides a
Nonius CAD-4 automatic four-circle diffractometer
(MoK or CuK radiation, graphite monochromator,
/2 scanning, scan rate 1 16.4 deg/min by . Crystal
stability was controlled by three control reflections
measured every 2 h and crystal orientation, by two
control reflexes centered every 200 measurements. No
intensity decay of the control reflections was observed.
The structure was solved by the direct method using
the SIR program. Data processing and structure
refinement were carried out using the MolEN program
package on an AlphaStation 200 [24]. The refinement
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
855
Table 6. Parameters of the crystals of compounds VIII XII and conditions of the X-ray diffraction experiments
Parameter
Color, habitus
VIII
IX
X
XI
XII
colorless
needles
colorless prisms
Unit cell parameters
a,
b,
c,
, deg
, deg
, deg
9.26(1)
10.657(6)
11.054(7)
80.45(5)
76.77(8)
74.57(8)
1017(2)
542.68
9.905(4)
10.499(5)
11.946(3)
106.86(3)
110.82(3)
99.87(3)
9.308(6)
10.902(4)
11.56(1)
77.33(3)
75.11(5)
75.16(5)
1081(2)
564.22
9.314(2)
11.462(2)
11.394(3)
74.54(2)
80.99(2)
75.43(2)
1129.4(2)
608.25
7.180(2)
12.259(3)
14.119(3)
64.60(2)
86.33(2)
86.75(2)
1119.7(5)
658.21
Volume, A3
Molecular weight
Specific gravity
dcalc, g/cm3
Absorption coefficient
1057.6(8)
526.25
1.773
3.718
1.652
22.286
1.733
24.051
1.788
2.526
1.952
2.865
1
, cm
F(000)
540
528
560
604
324
Radiation ( ,
)
MoK
0.71073
CuK
1.54184
78.4
MoK
0.71073
27.4
0.68 + 0.4tan
range
Scan angle
2.12
27.4
4.2
2.12
0.68 + 0.4tan
1.2 + 0.35tan
Standard reflexes
Two control by orientation and three control by intensity
every 200 reflections
Index range
0
h
10
11
12
10 h
11 k
12 l
9
0
13
0 h
11 k
22 l
9
10
22
10 h
12 k
14 l
0
12
11
8 h
15 k
17 l
8
13
0
11 k
11 l
2935
509
Reflections measured
Reflections with
2875
2600
5044
2692
3181
1998
4294
2839
I > 3 (I)
Allowance for absorption
Conditions of location
and refinement of
hydrogen atoms
not applied
empirical
not applied
Revealed from
the difference
series,
Revealed from the difference series,
refined isotropically
Revealed from
the difference
series,
not refined
not refined
Final divergence factors
R
RW
0.086
0.091
2.276
0.00
713
0.038
0.055
2.242
0.02
2520
364
0.048
0.066
2.659
0.01
1954
370
0.036
0.044
1.520
0.00
2055
392
0.056
0.064
2.170
0.00
2521
370
Fitting parameter
/
Reflections refined
Parameters refined
147
a
Triclinic syngony, space group P-1 (P1bar), Z = 2.
was carried out by the full-matrix least-squares pro-
cedure, the minimized function was w( FO
FC )2, extinction was not considered. The weight
scheme was 4F2o/[ (I)2 + (0.04F2o)]2. The cell param-
eters and details of data collection and refinement
of structures VIII XII are given in Table 6. All
drawings and analysis of intermolecular interactions
were carried out by means of the PLATON program
[18]. The principal geometric parameters are listed
in Tables 2 5.
Fluoroalkoxy-5,6-benzo-1,3,2-dioxaphospho-
rinan-4-ones I VI. To a solution of 0.05 mol of
2-chloro-5,6-benzo-1,3,2-dioxaphosphorinan-4-one in
100 ml of anhydrous ether, a solutiuon of 0.05 mol of
fluorinated alcohol and triethylamine was added
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

856
GUBAIDULLIN et al.
dropwise with stirring at 30 C. The reaction mixture
was stirred for 3 h until it achieved 20 C. The pre-
cipitate was filtered off, and the solvent was removed.
The residue was dried in a vacuum (0.02 mm Hg) and
then distilled. Phosphites I VI were obtained as
viscous colorless oils.
d2 51:49. Found, %: C 51.40; H 3.54. C16H12F3O5P.
Calculated, %: C 51.61; H 3.23.
2-[2,2,2-Trifluoro-1-(3-trifluoromethylphenyl)-
ethoxy]-5,6-benzo-1,3,2-dioxaphosphorinan-4-one
(IV). Yield 60%, bp 126 128 C (0.02 mm Hg), mp
1
68 70 C. IR spectrum, , cm : 2920, 2860, 1745,
1655, 1600, 1570, 1340 1345 sh., 1330, 1280, 1255,
1220, 1150 1180, 1120, 1090, 1050 1060, 1030,
1000, 970 980, 910, 890, 870, 860, 820, 790, 780,
740, 700, 680. 31P {1H} (121.42 MHz, acetone-d6),
P, ppm (J, Hz): 126.59 q (4JPOCCF 4.5, d1); 124.26 q
(4JPOCCF 4.5, d2); d1 :d2 52.4:47.6. 19F NMR spec-
trum, F, ppm (J, Hz): d1 60.51 br.m (CF3), 75.48
2-(2,2,2-trifluoro-1-phenylethoxy)-5,6-benzo-
1,3,2-dioxophosphorinan-4-one (I). Yield 65%, bp
128 C (0.02 mm Hg), mp 62 64 C. IR spectrum, ,
1
cm : 2900, 1730, 1600, 1580, 1455 1460, 1375,
1350, 1280 1290, 1230, 1202, 1170 1180, 1100
1130, 1040 1045, 960 980, 905 912, 890, 880, 850,
820, 780, 740 750, 700, 670. 1H NMR spectrum
(300 MHz, CCl4 + 50% acetone-d6), , ppm, (J, Hz):
6.85, 7.09, 7.18, 7.41, 7.52, 7.60 7.70, 8.18 all m
(C6H4, C6H5, 9H), 5.90 q.d and 5.91 q.d (POCH,
3JHCCF 6.6, 3JPOCH 8.7 9.0, 1H). 31P {1H}
(121.42 MHz, acetone-d6) P, ppm (J, Hz): 126.59 q
(4JPOCCF 4.4, d1); 124.26 q (4JPOCCF 4.4, d2); d1 :d2
52.4:47.6. 19F NMR spectrum, F, ppm (J, Hz):
3
m (4JPOCCF 4.5, JFCCH 4.6, d1); 60.55 br.s (CF3),
3
75.39 m (4JPOCCF 4.5, JFCCH 4.6, d2). Found, %: C
47.05; H 2.61. C16H9F6O4P. Calculated, %: C 46.83;
H 2.20.
2-(2,2,3,3,4,4,4-heptafluoro-1-phenylbutoxy)-5,6-
benzo-1,3,2-dioxaphosphorinan-4-one (V). Yield
65%, bp 124 128 C (0.02 mm Hg), mp 67 70 C. IR
4
75.16 m (3JHCCF 6.6, JPOCCF 4.5, d1); 75.24 m
1
spectrum, , cm : 3060, 2860, 1750, 1680, 1600,
(3JHCCF 6.2; JPOCCF 4.5, d2). Found, %: C 52.40; H
1675, 1535, 1470, 1455, 1390, 1335, 1280, 1200
1230, 1165 1180, 1140, 1100, 1075, 1010, 995, 960,
940, 900, 860, 840, 745 sh, 740, 715, 685, 640. 31P
{1H} NMR spectrum (121.42 MHz, 1:1 CCl4
acetone-d6), P, ppm: 125.88 br.s (d1), 123.98 br.s
(d2), d1 :d2 50.5:49.5. 19F NMR spectrum (acetone-
2.70. C15H10F3O4P. Calculated, %: C 52.63; H 2.92.
2-[1-(3-Chlorophenyl)-2,2,2-trifluoroethoxy]-5,6-
benzo-1,3,2-dioxaphosphorinan-4-one (II). Yield
62%, bp 136 138 C (0.02 mm Hg). IR spectrum, ,
1
cm : 3040, 1750, 1680, 1600, 1575, 1470, 1450,
3
d6), F, ppm (J, Hz): 78.91 d.d (CF3, JF CCF 9.0,
1425, 1350, 1260 1285, 1175 1225, 1130, 1100
1110, 1025 050, 1000 1010, 950, 895, 825 850, 805,
780, 745, 710, 680. 13P {1H) NMR spectrum
(121.42 MHz, 1:1 CCl4 :acetone-d6), P, ppm (J, Hz):
125.6 q (4JPOCCF 4.5, d1); 123.17 q (JPOCF 4.5, d2);
d1 :d2 50.2; 48.8. 19F NMR spectrum, F, ppm (J, Hz):
A
3
3JF CCF 12.1, d1); 79.03 d.d (CF3, JF CCF 9.0,
B
3JF CCF 12.0, d2), 123.5 123.8 m (CF2CF2A, d1, d2).
B
Found, %: C 46.40; H2.62. C17H10F7O4P. Calculated,
%: C 46.15; H 2.26.
2-[1-Methyl-1-(perfluorocyclohexyl)ethoxy]-5,6-
benzo-1,3,2-dioxaphosphorinan-4-one (VI). Yield
3
74.75 m (4JPOCCF 4.5, JFCCH 4.6, d1); 74.82 m
3
(4JPOCCF 4.5, JFCCH 4.6, d2). Found, %: C 47.60; H
71%, bp 99 100 C (0.02 mm Hg). IR spectrum,
,
1
2.40. C15H9 ClF3O4P. Calculated, %: C 47.80; H 2.39.
cm : 3100, 2960, 1760, 1610, 1570, 1460, 1330,
1280, 1240, 1180, 1120, 1090, 1060, 1030, 1000, 970,
910, 890, 870, 860, 820, 790, 780, 760, 740, 700, 680.
31P {1H} NMR spectrum (121.42 MHz, acetone-d6),
P, ppm: 125.65 br.s (d1), 124.49 br.s (d2), d1 :d2
1:1. Found, %: C 36.70; H 1.81. C15H8F11O4P.
Calculated, %: C 36.58; H 1.63.
2-[2,2,2-Trifluoro-1-(3-methoxyphenyl)ethoxy]-
5,6-benzo-1,3,2-dioxaphosphrinan-4-one (III).
Yield 58%, bp 152 154 C (0.02 mm Hg). IR spec-
1
trum, , cm : 3080, 2940, 1750, 1690, 1600, 1580,
1485, 1460, 1430, 1350, 1280, 1260, 1170, 1130,
1030, 1000, 930, 900, 860, 840, 820, 775, 750, 700,
680. 31P {1H} NMR spectrum (121.42 MHz, acetone-
d6), P, ppm: 123.25 br.s (d1), d2 121.82 br.s (d2); d1;
Reaction of phosphorinanes I VI with hexaflu-
oroacetone (general procedure). A solution of 0.01
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

SYNTHESIS AND COMPARATIVE ANALYSIS OF THE STERIC
857
0.015 mol of phosphorinane I VI in 30 ml of CH2Cl2
was treated at 40 C with 0.015 0.02 mol of hexa-
fluoroacetone under argon. The reaction mixture was
gradually (2 3 h) heated to 20 C. After a day, the
solvent and excess hexafluoroacetone were removed.
The residue was phosphepine VII XII (colorless
viscous oil), quantitative yield. It was a mixture of
diastereomers in a ratio similar to that in the starting
phosphite. The oil was dissolved in a mixture of 10
20 ml of methylene chloride and diethyl ether and left
to stand for 10 20 days at 0 5 C. Crystals of indi-
vidual diastereomers precipitated (yield 37 43%) and
were filtered off, washed with a cold mixture of
methylene chloride and pentane, and dried in a
vacuum (12 mm Hg). The crystals used for X-ray
studies were recrystallized from acetone.
1300, 1280, 1220 1260, 1200, 1190, 1140, 1120,
1060, 1040, 980, 950, 918 sh, 885, 850, 790, 770 sh,
715, 690, 670, 650, 640, 600, 565, 530, 510, 490, 465,
430. 31P {1H} NMR spectrum (162.0 MHz, CCl4),
P, ppm: 15.7 s and 15.8 s. Isolated diastereomer.
mp
121 125 C.
31P {1H}
NMR
spectrum
(162.0 MHz, CCl4):
15.0 ppm. 19F {1H} NMR
spectrum (188.3 MHz,Pacetone-d6), F, ppm (J, Hz):
4
69.3 q and 70.81 q [C(CF3)2, JFCCCF 9.3], 75.14 s
(CHF3). Found, %: C 42.40; H 1.86. C19H12F9O6P.
Calculated, %: C 42.38; H 2.23.
4,4-Bis(trifluoromethyl)-2-[2,2,2-trifluoro-1-(3-
5
trifluoromethylphenyl)ethoxy]-6,7-benzo-1,3,2
-
dioxaphosphepin-5-one 2-oxide (X). Diastereomeric
mixture. 31P{1H} NMR spectrum (162.0 MHz, CCl4),
P, ppm: 16.9 s and 16.2 s. Isolated diastereomer.
4,4-Bis(trifluoromethyl)-2-(2,2,2-trifluoro-1-
1
5
mp 87 90 C. IR spectrum, , cm : 2940, 2870, 1720,
phenylethoxy)-6,7-benzo-1,3,2 -dioxaphosphepin-
1605, 1575, 1540, 1520, 1455, 1330, 1320, 1267,
1240, 1220, 1190, 1155, 1125, 1110, 1075, 1050, 980,
960, 930, 890, 850, 805, 790, 770, 740, 710, 660, 630,
625 sh, 615, 590, 570, 550, 525, 510, 480, 411. 31P
5-one 2-oxide (VII) Diastereomeric mixture. 31P
{1H} NMR spectrum (162.0 MHz, CCl4), P, ppm:
115.32 s and 15.55 s. Isolated diastereomer. mp
{1H} NMR spectrum (CCl4):
16.12 ppm. Found,
1
115 124 C. IR spectrum, cm : 2940, 2860, 1720,
P
%: C 39.40; H 1.86. C19H9F12O6P. Calculated, %: C
39.58; H 1.56.
1600, 1330, 1265 1275, 1240 1250, 1210, 1180,
1130, 1110, 1075, 1050, 975, 930, 920, 885, 790, 775,
750, 740, 700, 680, 660, 630, 610, 590, 550, 570, 550,
525, 490, 460. 31P {1H} NMR spectrum (162.0 MHz,
4,4-Bis(trifluoromethyl)-2-(2,2,3,3,4,4,4-hepta-
5
fluoro-1-phenylbutoxy)-6,7-benzo-1,3,2 -dioxa-
phosphepin-5-one 2-oxide (XI). Diastereomeric
mixture. 31P {1H} NMR spectrum (162.0 MHz, CCl4),
CCl4):
15.35 ppm. Found, %: C 42.40; H 1.86.
P
C18H10F9O5P. Calculated, %: C 42.52; H 1.97.
P, ppm: 15.71 s and 16.2 s. Isolated diastereomer.
mp 122 124 C. IR spectrum, , cm 1: 2940, 2870,
1720, 1692, 1650, 1605, 1580, 1400, 1340, 1315,
1275, 1230 1240, 1205, 1190, 1160, 1140, 1120,
1110, 1050, 1030, 985, 980, 950, 930, 910, 880, 850,
780, 750, 730, 710, 660, 640, 600, 590, 560, 505, 490,
460. 31P {1H} NMR spectrum (162.0 MHz, CCl4):
16.3 ppm. Found, %: C 39.08; H 1.71. C20H10
FP13O5P. Calculated, %: C 39.47; H 1.64.
4,4-Bis(trifluoromethyl)-2-[1-(3-Chlorophenyl)-
2,2,2-trifluoroethoxy]-6,7-benzo-1,3,2 5-dioxa-
phosphepin-5-one 2-oxide (VIII). Diastereomeric
mixture. 31P {1H} NMR spectrum (162.0 MHz, CCl4),
P, ppm: 15.76 s and 16.06 s. Isolated diastere-
1
omer: mp 143 145 C. IR spectrum, , cm : 2930,
1730, 1700, 1610, 1590, 1320, 1275, 1250, 1220,
1195, 1170, 1145, 1100, 1050, 975, 965, 935, 920,
890, 850, 785, 770, 745, 730, 715, 700, 665, 650, 630,
615, 585, 550, 525, 510, 480, 440. 31P {1H} NMR
4,4-Bis(trifluoromethyl)-2-[1-methyl-1-(perflu-
orocyclohexyl)ethoxy]-6,7-benzo-1,3,2 5-dioxa-
phosphepin-5-one 2-oxide (XII). IR spectrum,
,
1
cm : 1730, 1710 sh, 1660, 1620, 1590, 1570, 1520,
1385, 1307, 1290, 1250, 1220, 1185, 1160, 1125,
1080, 1045, 1015, 1000, 965, 930, 900, 860, 820, 789,
spectrum (162.0 MHz, CCl4):
15.76 ppm. Found,
P
%: C 39.86, H 1.81. C18H9ClF9O5P. Calculated, %:
C 39.82, H 1.66.
1
766, 730, 675, 656, 640, 620, 600, 565, 520, 489. H
NMR spectrum (300 MHz, acetone-d6), , ppm (J,
3
4,4-Bis(trifluoromethyl)-2-[2,2,2-trifluoro-1-(3-
methoxyphenyl)ethoxy]-6,7-benzo-1,3,2 5-dioxa-
phosphepin-5-one 2-oxide (IX). Diastereomeric
Hz): 1.98 br.d.m (CH3, JHCCH 6.7) (d2), 2.05 br.d.t
3
4
4
(CH3, JHCCH 6.6, JPOCCH 1.9, JFCCCH 1.9) (d1), 6.0
3
4
6.07 m (CH, JHCCH 6.6 6.7, JFCCCH 1.9) (d1, d2),
1
3
4
7.62 br.d.d.d (H8, JH CCH 8.1, JH CCCH 1.5,
8
9
8
10
mixture. IR spectrum, , cm : 3080, 2980, 2940,
4
3
JPOCCH 1.3) (d2), 7.71 d.d.d (H8, JH CCH 8.2,
8
9
1795, 1725, 1700, 1650, 1615, 1600 sh, 1570 sh,
1560, 1525, 1500, 1465, 1445, 1370 1380, 1320,
JH CCCH d1 1.4, JPOCCH 1.2) (d1), 7.78 7.79 m (H10,
4
4
8
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004

858
GUBAIDULLIN et al.
3
4
3JH
7.8,
JH CCH
7.4,
JH CCCH
1.4,
10. Mironov, V.F., Litvinov, A.I., Gubaidullin, A.T., Ko-
9
10
8
10
10CCH11
6JPOCCCCH 1.2) (d1, d2), 8.01 and 8.02 two d.d (H11,
novalova, I.V., Zyablikova, T.A., Burnaeva, L.M.,
Romanov, S.V., and Azancheev, N.M., Zh. Obshch.
Khim., 2000, vol. 70, no. 11, pp. 1812 1832.
3JH
7.8, JH CCCH 1.7) (d1, d2), 8.11 8.12 m
4
9
11
10CCH11
(H9, 3JH CCH 8.2, JH CCCH 1.7, JPOCCH 1.2) (d1, d2).
4
5
8
9
9
11
11. Mironov, V.F., Gubaidullin, A.T., Burnaeva, L.M.,
Litvinov, I.A., Brazhnikova, I.A., Mastryukova, T.A.,
Goryunov, E.I., and Konovalova, I.V., Abstracts of
Papers, Yubileinaya sessiya Gorizonty organicheskoi
I elementoorganicheskoi khimii (Anniversary Session
Horizons of Organic and Organoelement Che-
mistry ), Moscow, 1999, vol. II, R70, p. 72; Miro-
nov, V.F., Burnaeva, L.M., Gubaidullin, A.T., Litvi-
nov, I.A., Mastryukova, T.A., Goryunov, E.I., Ko-
novalova, I.V., and Brazhnikova, I.A., Abstract of
Papers, XII Int. Conf. on the Chemistry of Phosphorus
Compounds, Kiev, 1999, p. 106; Burnaeva, L.M.,
Mironov, V.F., Konovalova, I.V., Goryunov, E.I.,
Mastryukova, T.A., Gubaidullin, A.T., Litvinov, I.A.,
and Yachagina, O.V., Abstracts of Papers, XV Int.
Conf. on Phosphorus Chemistry (ICPC16), Sendai
(Japan), 2001, PB040, p. 220.
Diastereomeric mixture. 31P {1H} NMR spectrum
(162.0 MHz, CDCl3), P, ppm: 15.85 and 16.62.
Isolated diastereomer. mp 48 50 C (from acetone).
31P {1H} NMR spectrum:
16.31 ppm. Found, %:
P
C 32.45; H 1.08. C18H8F17O5P4. Calculated, %: C
32.83, H 1.22.
ACKNOWLEDGMENTS
The work was financially supported by the Prog-
ram for Support of Leading Scientific Schools of
Russia (project no. 00-15-97424), Russian Foundation
for Basic Research (project no. 02-03-32280), and
Universities of Russia Program (UR.05.01.016).
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