Some reactions of O-equatorial spirophosphoranes bearing the bidentate ligand based on decafluoro-3-phenyl-3-pentanol

Article abstract of DOI:10.3987/COM-07-S(U)61

Some reactions of O-equatorial and O-apical methylphosphoranes bearing two bidentateligands consisted of1,1,1,2,2,4A,5,5,5-decafluoro-3-phenyl-3-pentanol were examined. Not only the O-apical phosphorane, but also the O-equatorial isomer did not react with MeLi as a nucleophile at the phosphorus center. This should be due to the steric bulkiness of the C₂F₅ group. For both isomers, deprotonation at the methyl group was achieved using Superbase (t-BuOK/n-BuLi) to give the corresponding α-anion, which was treated with several electrophiles to afford new phosphorane derivatives. The O-equatorial and O-apical phosphoranes having a β-hydroxyethyl group as the monodentate ligand were synthesized. It was found that under basic conditions,. the O-apical phosphorane could be converted into the O-equatorial isomer via hexacoordinate phosphate intermediates.

Full text of DOI:10.3987/COM-07-S(U)61

HETEROCYCLES, Vol. 73, 2007
805
HETEROCYCLES, Vol. 73, 2007, pp. 805 - 824. © The Japan Institute of Heterocyclic Chemistry
Received, 6th August, 2007, Accepted, 5th September, 2007, Published online, 7th September, 2007. COM-07-S(U)61
SOME REACTIONS OF O-EQUATORIAL SPIROPHOSPHORANES
BEARING THE BIDENTATE LIGAND BASED ON
DECAFLUORO-3-PHENYL-3-PENTANOL
Xin-Dong Jiang, Shiro Matsukawa, Hideaki Yamamichi, and Yohsuke
Yamamoto*
Department of Chemistry, Graduate School of Science, Hiroshima University,
1-3-1 Kagamiyama, Higashi-hiroshima 739-8526, Japan
Fax: +81-82-424-0723, Email: yyama@sci.hiroshima-u.ac.jp
Abstract – Some reactions of O-equatorial and O-apical methylphosphoranes
bearing two bidentate ligands consisted of 1,1,1,2,2,4,4,5,5,5-decafluoro-
3-phenyl-3-pentanol were examined. Not only the O-apical phosphorane, but also
the O-equatorial isomer did not react with MeLi as a nucleophile at the
phosphorus center. This should be due to the steric bulkiness of the C2F5 group.
For both isomers, deprotonation at the methyl group was achieved using
Superbase (t-BuOK/n-BuLi) to give the corresponding α-anion, which was
treated with several electrophiles to afford new phosphorane derivatives. The
O-equatorial and O-apical phosphoranes having a β-hydroxyethyl group as the
monodentate ligand were synthesized. It was found that under basic conditions,
the O-apical phosphorane could be converted into the O-equatorial isomer via
hexacoordinate phosphate intermediates.
INTRODUCTION
Hypervalent phosphorus compounds have attracted great interest because such species are assumed to be
involved as intermediates (or transition states) in the biological phosphoryl transfer reaction.1 Our group
succeeded in isolating an isomeric pair of 10-P-52 phosphoranes (O-equatorial and O-apical) for the first
time.3 During the course of our study on the reactivity of both isomers, we reported that the O-equatorial
spirophosphorane bearing the Martin ligands 1 showed an enhanced reactivity toward nucleophiles

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HETEROCYCLES, Vol. 73, 2007
compared to its stable isomer 2 (O-apical) (Figure 1).4 For example, the reaction of 1 with MeLi afforded
the monocyclic phosphorane 3, while 2 did not react with MeLi under similar conditions (Scheme 1).
This finding could be interpreted by the presence of a lower-lying σ*P-O orbital as the reacting orbital in
the equatorial plane, whereas the corresponding orbital is a higher-lying σ*P-C orbital in the O-apical
isomer. This was supported by the theoretical calculations, in which the energy level of the σ*P-O orbital
of 1a was calculated to be lower than that of the σ*P-C orbital of the O-apical isomer 2a by 18.7 kcal
mol–1.4 Moreover, the O-equatorial benzylic anion α to the phosphorus atom 4 was revealed to be more
stable than the corresponding O-apical anion 5.4 This finding could also be explained by the existence of a
strong nC→σ*P-O interaction in the O-equatorial α-anion 4 (Scheme 2).
*
!
P-O orbital
Nu
F3C CF3
O
F3C CF3
O
Nu
P
R
Nu
P
R
Nu
F3C
F3C
O
O
Nu
Nu
F3C CF3
1
2
O-apical
O-equatorial
Figure 1
F3C
CF3
F3C
CF3
CF3
CF3
Me
HO
O
O
P
MeLi
P
R
O
R
F3C
F3C
1a: R = Me
Me
3a: R = Me
3b: R = n-Bu
1b: R = n-Bu
F3C
CF3
O
Me
MeLi
No reaction
P
R
O
F3C
CF3
2a: R = Me
2b: R = n-Bu
Scheme 1

HETEROCYCLES, Vol. 73, 2007
807
F3C
CF3
O
F3C
CF3
O
F3C
CF3
O
F3C
CF3
O
K(18-crown-6)
K(18-crown-6)
+
+
P
P
P
P
O
O
F3C
F3C
F3C
O
O
F3C
F3C
CF3
F3C
CF3
1c
5
4
2c
stable !-anion
Scheme 2
Very recently, we developed a new bidentate ligand based on decafluoro-3-phenyl-3-pentanol (B), and
synthesized a family of pentacoordinate phosphoranes using this ligand. The kinetic study of the
isomerization (6a to 7a) unambiguously showed that the steric bulkiness of the C2F5 group was effective
for freezing the pseudorotation (Scheme 3).5 Moreover, the bidentate ligand was also found to be
effective for freezing the pseudorotations of pentacoordinate organoarsenic compounds, providing the
first isolation of the anti-apicophilic 10-As-5 species.6 Therefore, it was of interest to investigate the steric
effect on the reactivity of the newly prepared phosphoranes (6 and 7). We now discuss the reactivity of
two isomeric phosphoranes bearing the C2F5 groups mainly focusing on the generation and reactions of
the carbanion α to the phosphorus atom.
Rf Rf
O
Rf Rf
Rf Rf
O
O
P
"G!
22.5 kcal mol–1
26.1 kcal mol–1
333
isomerization
P
Me
Me
1a ! 2a
6a ! 7a
O
Rf
Rf
O
A: Rf = CF3
Rf
Rf
(Martin ligand)
B: Rf = C2F5
1a: Rf = CF3
6a: Rf = C2F5
2a: Rf = CF3
7a: Rf = C2F5
Scheme 3
RESULTS AND DISCUSSION
Reaction with a nucleophile
We first briefly examined the reactivity of the O-equatorial phosphoranes (6a and 6b) toward a
nucleophile. When the O-equatorial 6a was treated with 3 equiv. of MeLi for 3 h at room temperature, the
phosphorane 7a, which is the more stable isomer of 6a, was obtained in 76% yield (Scheme 4). In this
reaction, the monocyclic phosphorane 8a could not be observed. Similarly, in the case of the n-butyl
derivative (6b), the O-apical isomer 7b was mainly obtained (6b : 7b = 1 : 8). On the other hand, for the
O-apical phosphoranes (7a and 7b), no reactions were observed under similar conditions as expected.

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HETEROCYCLES, Vol. 73, 2007
The nucleophilic reactions at the pentacoordinate phosphoranes are generally considered to take place
within the equatorial plane, i.e., the nucleophile attacks a σ*orbital of one of the three equatorial bonds
from the rear side.4 For the Martin ligand system, our group proved this assumption, i.e., the O-equatorial
1b reacted with MeLi to give the monocyclic phosphorane 3b accompanying the breaking of one of the
P—O bonds (Scheme 1).4 However, the experimental result that 6 does not react with MeLi implies that
the steric bulk of the pentafluoroethyl group could prevent the nucleophile (i.e., MeLi) from attacking the
σ*P-O orbital. The relatively rapid isomerization of 6 to 7 could be catalyzed by the lithium cation. Figure
2 shows the space filling models for the crystal structures of two O-equatorial n-butylphosphoranes 1b3
and 6b. It is clear that the reaction space toward the σ*P-O orbital of 6b is narrower than that of 1b.
Though the apical P—O bond of 6b (1.802(2) Å) is slightly (0.03 Å) longer than that of 1b (1.768(3) Å),
this small difference should not affect the crowding around the σ*P-O orbital.
F3CF2C
CF2CF3
CF2CF3
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
substrate
result
HO
O
CF2CF3
6a
8a: 0%
MeLi
+
P
P
R
P
R
7a: 76%
O
R
F3CF2C
F3CF2C
6a: R = Me
O
Me
6b
8b: 0%
F3CF2C
CF2CF3
6b:7b = 1:8
8a: R = Me
8b: R = n-Bu
7a: R = Me
7b: R = n-Bu
6b: R = n-Bu
F3CF2C
CF2CF3
O
P
MeLi
No reaction
R
O
F3CF2C
CF2CF3
7a: R = Me
7b: R = n-Bu
Scheme 4
Figure 2. Space-filling representation of the crystal structure of n-butylphosphoranes (left: 1b,3 right: 6b)
viewed along the equatorial P—O bond.

HETEROCYCLES, Vol. 73, 2007
809
Generation of an α-carbanion from O-equatorial methylphosphorane 6a
The result that no reaction between the σ*P-O orbital of 6a and MeLi was observed gave us a chance to
generate an α-carbanion adjacent to the phosphorus atom without suffering from any nucleophilic side
reactions. Therefore, we next examined the deprotonation at the methyl group of 6a (Scheme 5 and Table
1). Using conventional strong bases (n-BuLi, t-BuLi, LDA, and NaHMDS), after quenching the reaction
with D2O, the starting material 6a was recovered without being deuterated along with undeuterated
O-apical phosphorane 7a (Table 1). The ratio of 7a ranged from 50 to 11% based on the 1H NMR results.
Apparently, such bases do not have the ability to deprotonate 6a. Instead, they accelerated the
stereomutation of 6a to 7a. It may imply that the lithium or sodium cation interacts with the oxygen
atoms of 6a to elongate the P—O bonds, and this might accelerate the isomerization of 6a to 7a.
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
1) Base
2) D2O
+
P
CH3
P
CH3
P
CH3
O
O
F3CF2C
F3CF2C
F3CF2C
F3CF2C
O
F3CF2C
CF2CF3
6a
6a
7a
Base = n-BuLi, t-BuLi, LDA, or NaHMDS
Scheme 5
Table 1. Attempted deprotonation of 6a using convensional strong bases.
entry
base
solvent condition
Et2O rt, 0.25 h
resulta
1
2
3
4
t-BuLi (1.2 eq.)
n-BuLi (1.2 eq.)
LDA (1.2 eq.)
6a : 7a = 50 : 50
THF 0 °C, 0.5 h 6a : 7a = 73 : 27
THF rt, 0.5 h
6a : 7a = 87 : 13
NaHMDS (1.2 eq.) THF rt, 0.5 h
6a : 7a = 89 : 11
a: Product ratio was calculated on the basis of the integral values in 1H NMR.
Next, we chose the much stronger base, "Superbase",7 which is a mixture of t-BuOK and n-BuLi (Scheme
6). When 6a was treated with 1.5 equiv. of the Superbase prepared using solid t-BuOK, followed by the
addition of MeI, 6a was completely recovered (entry 1 in Table 2).8 On the other hand, using 2 equiv. of
the Superbase prepared using a THF solution of t-BuOK, a mixture of 9a and 6a (9a : 6a = 83 : 17 based
31
on P NMR) was obtained (entry 2). These results obviously show that THF as the co-solvent is crucial
for the deprotonation of 6a, indicating that activation of the Superbase is needed.
The quantity of Superbase and the reaction time were examined in order to optimize the yield of 9a. We
found that 2 equiv. of Superbase and a 1 h reaction time were suitable for the generation of the

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HETEROCYCLES, Vol. 73, 2007
α-carbanion (entry 2). In these experiments, the starting material 6a was recovered in all the experiments,
and a longer reaction time provided a greater amount of 6a. This should result from the proton abstraction
of the α-carbanion from THF as the co-solvent. During these examinations, the O-apical isomers (7a or
10a) were not observed at all (Scheme 6). This implies that the O-equatorial α-carbanion (11-K) is
stabilized due to strong nC→σ*P-O interaction, therefore, 11-K does not isomerize into the corresponding
O-apical isomer (12-K) at room temperature.
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
t-BuOK/n-BuLi
MeI
P
CH3
P
CH2
P
CH2CH3
O
O
O
n-hexane/THF
rt.
F3CF2C
F3CF2C
F3CF2C
F3CF2C
F3CF2C
F3CF2C
K
6a
11-K
9a
F3CF2C
CF2CF3
F3CF2C
CF2CF3
O
O
P
MeI
CH2
P
CH2CH3
O
O
K
F3CF2C
CF2CF3
12-K
F3CF2C
CF2CF3
10a
Scheme 6
Table 2. Examination of α-carbanion (11-K) generation using Superbase in n-hexane.
entry Superbasea (eq.) THFd (%) time (h)e resultf
1
2
3
4
5
6
1.5b
2c
0.0
3.0
3.0
3.0
4.5
4.5
1
1
3
5
1
3
6a : 9a = 100 : 0
6a : 9a = 17 : 83
6a : 9a = 30 : 70
6a : 9a = 48 : 52
6a : 9a = 26 : 74
6a : 9a = 51 : 49
2c
2c
3c
3c
a: A 1 : 1 mixture of t-BuOK and n-BuLi. b: Solid t-BuOK was used. c: A THF (1 M)
solution of t-BuOK was used. d: Content of the co-solvent THF. e: Reaction time for the
1
deprotonation. f: Product ratio was calculated on the basis of the integral values in H
NMR.
Reactions of α-anion 11-K with electrophiles
The α-anion (11-K) reacted with several electrophiles to afford new phosphoranes (Scheme 7, Table 3).

HETEROCYCLES, Vol. 73, 2007
811
When the α-anion 11-K was treated with BrCF2CF2Br, the O-apical bromomethylphosphorane 10b was
obtained in 50% yield, however, the corresponding O-equatorial isomer (9b) was not observed (entry 1 in
Table 3). As already described, the O-equatorial α-anion 11-K does not isomerize into the corresponding
O-apical isomer (12-K) even after 6 h at room temperature. Thus, the O-equatorial 9b would be generated
just after the addition of BrCF2CF2Br and rapidly isomerizes into the O-apical 10b. Using ICH2CH2I or
PhSeBr as an electrophile, both the O-equatorial and O-apical phosphoranes were obtained. For the
iodomethyl derivative, the O-equatorial 9c gradually isomerized to the O-apical isomer 10c at room
temperature in solution, indicating that the assumption for the bromomethyl derivative should be valid.
The yield of 9c was found to be highly dependent on the temperature. Therefore, the reaction and the
workup including extraction, washing and evaporation, were carried out at 0 °C, and the purification time
using HPLC needed to be as short as possible for preventing the isomerization. On the other hand, the
O-equatorial phenylselenomethyl derivative (9d) is stable in solution at room temperature.
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
O
Electrophile
P
CH2R'
P
CH2
P
CH2R'
+
O
O
F3CF2C
F3CF2C
F3CF2C
F3CF2C
O
F3CF2C
CF2CF3
K
11-K
9b: R' = Br
9c: R' = I
9d: R' = SePh
10b: R' = Br
10c: R' = I
10d: R' = SePh
Scheme 7
Table 3. Reaction of α-anion 11-K with electrophiles.
entry electrophile temp., time R’
yield
1
2
3
BrCF2CF2Br 0 ˚C, 1 h
Br
I
9b: 0%, 10b: 50%
9c: 52%, 10c: 5%
ICH2CH2I
PhSeBr
0 ˚C, 2 h
r.t., 2.5 h
SePh 9d: 18%, 10d: 14%
Qualitatively, the isomerization rates (6a to 7a5 < 9d to 10d < 9c to 10c < 9b to 10b) depend on the order
of the electronegativity of substituent R’ {Pauling's electronegativity scale: H (2.20) < Se (2.55) < I (2.66)
< Br (2.96)}.9,10 As previously proposed by our group,11 during the stereomutation from 9 to 10, the
highest energy isomer bearing a more electronegative substituent at the apical site (13) becomes more
stable; therefore, this reduces the activation free energy (ΔG≠) of the stereomutation of 9 to 10 (Scheme 8).
It should be noted that such O-equatorial compounds with an electronegative substituted methyl group
were isolated for the first time in the C2F5 series, whereas in the CF3 system, even the O-equatorial
methylphosphorane (1a) was not stable to isomerization.12

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HETEROCYCLES, Vol. 73, 2007
CF2CF3
F3CF2C
O
CF2CF3
P
O
CF2CF3
CH2R'
F3CF2C
CF2CF3
O
13b: R' = Br
13c: R' = I
13d: R' = SePh
P
CH2R'
O
F3CF2C
CF2CF3
O
F3CF2C
F3CF2C
P
CH2R'
!G!
9b: R' = Br
9c: R' = I
9d: R' = SePh
O
F3CF2C
CF2CF3
10b: R' = Br
10c: R' = I
10d: R' = SePh
Scheme 8
Figure 3. The ORTEP drawings of phosphoranes (9a, 9c, 9d, 10b, 10c and 10d) showing the thermal
ellipsoids at the 30% probability level. The hydrogen atoms are omitted for clarity.

HETEROCYCLES, Vol. 73, 2007
813
Table 4. Selected bond lengths (Å) and angles (deg) for the phosphoranes.
Compound
9a
9c
9d
10b
10c
10d
Bond lengths (Å)
P1—O1
1.7775(17) 1.787(4) 1.772(3)
1.6585(19) 1.657(4) 1.655(3)
1.746(4) 1.747(3)
1.746(4) 1.748(3)
1.829(5) 1.829(4)
1.829(5) 1.824(3)
1.855(11) 1.823(4)
1.745(4)
1.754(4)
1.830(5)
1.830(5)
1.815(5)
P1—O2
P1—C1
1.828(2)
1.874(3)
1.839(3)
1.870(6) 1.825(4)
1.830(5) 1.886(4)
1.836(5) 1.845(4)
P1—C2
P1—C3
Bond angles (deg)
O1—P1—O2
O1—P1—C1
O1—P1—C2
O1—P1—C3
O2—P1—C1
O2—P1—C2
O2—P1—C3
C1—P1—C2
C1—P1—C3
C2—P1—C3
83.57(9)
86.23(9)
82.96(18) 82.77(13) 171.70(4) 171.89(13) 171.15(18)
86.30(2) 86.47(15) 87.40(2) 87.10(14) 87.20(2)
170.72(11) 171.00(2) 170.56(15) 89.70(2) 89.94(15) 90.10(2)
89.37(11) 87.70(2) 89.84(18) 94.12(15) 94.30(15) 94.40(2)
119.54(10) 121.40(2) 122.52(16) 89.50(3) 89.49(15) 89.40(2)
87.27(11) 88.30(2) 87.79(15) 87.40(2) 87.43(15) 86.60(2)
120.40(14) 116.70(2) 115.37(17) 94.12(15) 93.77(16) 94.50(2)
99.63(11) 100.50(3) 98.91(17) 139.10(4) 136.24(16) 135.30(2)
118.87(14) 120.10(2) 120.89(18) 110.50(2) 109.15(16) 112.00(2)
94.01(13) 94.00(3) 93.97(19) 110.50(2) 114.62(16) 112.60(2)
The structures of the pentacoordinate phosphoranes 9a, 9c, 9d, 10b, 10c and 10d were confirmed by
X-ray analysis (Figure 3), showing that all the structures were regarded as having a distorted trigonal
bipyramidal (TBP) geometry. The selected bond lengths and angles are summarized in Table 4.
Novel conversion of the O-apical phosphorane to the O-equatorial isomer via hexacoordinate
phosphates
We also synthesized an isomeric pair of β-hydroxyethylphosphoranes 14 and 15 by the reaction of the
α-carbanion derived from 6a and 7a with paraformaldehyde (Scheme 9). The structures of these
phosphoranes were confirmed by a single crystal X-ray analysis (Figure 4).
The treatment of 14 and 15 with KH afforded a hexacoordinate phosphate bearing an oxaphosphetane
ring 16 (31P NMR: δ = –97.3 ppm in THF) and 17 (–104.4 ppm), respectively. These highly
upfield-shifted 31P signals were similar to those of the reported hexacoordinate oxaphosphetane
anions.4,13-15 Surprisingly, when a THF solution of 17 was heated at 60 ˚C, 17 gradually isomerized to 16
(Scheme 10 and Figure 5). This means that the O-apical phosphorane can be converted into the
O-equatorial isomer under basic conditions. Actually, when a mixture of 15 and KH was heated at 60 ˚C

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HETEROCYCLES, Vol. 73, 2007
for 8.5 h, followed by the addition of NH4Cl aq., we could obtain the O-equatorial phosphorane 14 in
77% yield. As expected, the thermal conversion of 14 to 15 occurred almost quantitatively. These results
indicate that 14 and 15 are capable of interconverting with each other in this system.
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
1) t-BuOK/n-BuLi
2) (CH2O)n
O
P
OH
P
CH3
O
O
n-hexane/THF
rt
F3CF2C
F3CF2C
F3CF2C
F3CF2C
6a
14
F3CF2C
CF2CF3
O
F3CF2C
CF2CF3
1) t-BuOK/n-BuLi
2) (CH2O)n
O
P
OH
P
CH3
n-hexane/THF
rt
O
O
F3CF2C
CF2CF3
F3CF2C
CF2CF3
7a
15
Scheme 9
Figure 4. The ORTEP drawings of β-hydroxyethylphosphoranes (14 and 15) showing the thermal
ellipsoids at the 30% probability level. The hydrogen atoms, except for the hydroxyl proton, are omitted
for clarity.

HETEROCYCLES, Vol. 73, 2007
815
Figure 5. Time course of the 31P NMR for the conversion of 17 to 16 at 60 ˚C in THF.
F3CF2C
CF2CF3
F3CF2C
CF2CF3
O
P
O
O
P
KH/18-crown-6
H+
OH
O
O
F3CF2C
F3CF2C
K (18-crown-6)
F3CF2C
F3CF2C
14
16
80 ˚C, 9 h
97%
60 ˚C, 8.5 h
77% (15 to 14)
F3CF2C
CF2CF3
F3CF2C
CF2CF3
O
P
O
O
P
OH KH/18-crown-6
H+
O
O
K (18-crown-6)
F3CF2C
CF2CF3
F3CF2C
CF2CF3
15
17
Scheme 10

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HETEROCYCLES, Vol. 73, 2007
F3C
CF3
O
F3C
CF3
O
Ph
Ph
Slow
O
+
P
O
P
O
> 60 ˚C in THF
F3C
F3C
Ph
O
Ph
F3C
F3C
CF3
K (18-crown-6)
18
CF3
O
F3C
CF3
O
Ph
Ph
Fast
O
+
P
O
P
> –60 ˚C in THF
Ph
O
O
Ph
F3C
CF3
F3C
CF3
19
Na
Scheme 11
We have already clarified that the O-apical phosphoranes are more stable than the O-equatorial isomers.
All the O-equatorial phosphoranes that we isolated so far irreversibly isomerized into the O-apical
counterparts, and the diffirence in energy was estimated to be more than 12 kcal mol–1 for the
n-butylphosphoranes.3 On the other hand, as for the stability of the hexacoordinate species, our group
have demonstrated that the phosphate 18 derived from the O-equatorial phosphorane shows a higher
stability toward decomposition than 19 derived from the O-apical phosphorane (Scheme 11).4,15 The
phosphate 18 has one oxygen atom trans to the oxygen of the four-membered ring, indicating that the
trans influence is highly related to the stability of the phosphates bearing an oxaphosphetane ring. This is
in good agreement with the relative stability in the present system (16 > 17). Since both 16 and 17 were
not thermally decomposed upon heating at 60 ˚C, unlike the case of 18 or 19, we could directly observe
the stereomutation of 17 to 16, giving rise to determining the thermodynamic relative stability of the two
isomeric hexacoordinate phosphates.
In conclusion, we presented some reactions of the O-equatorial and O-apical spirophosphoranes (6a and
7a). No nucleophilic reaction at the phosphorus atom was observed in both cases. We found that the
reaction of 6a with the Superbase afforded the α-carbanion adjacent to the phosphorus atom (11-K),
which was treated with some electrophiles (BrCF2CF2Br, ICH2CH2I, and PhSeBr) to produce new
phosphorane derivatives. Using the β-hydroxyethylphosphoranes (14 and 15), we found a novel
interconversion between the O-apical and O-equatorial phosphoranes. The vequatorial 14 was almost
quantitatively converted into the O-apical 15 under neutral conditions, whereas the O-apical 15 could be
converted into the O-equatorial 14 in 77% yield under anionic conditions involving the hexacoordinate
intermediates 16 and 17.

HETEROCYCLES, Vol. 73, 2007
817
EXPERIMENTAL
General.
1
The melting points were measured using a Yanaco micro melting point apparatus. The H NMR (400
19 31
MHz), F NMR (376 MHz), and P NMR (162 MHz) spectra were recorded using a JEOL EX-400 or a
1
JEOL AL-400 spectrometer. The H NMR chemical shifts (δ) are given in ppm downfield from Me4Si,
19
31
determined by residual chloroform (δ 7.26). The F and P NMR chemical shifts (δ) are given in ppm
downfield from the external CFCl3 and 85% H3PO4, respectively. The elemental analyses were performed
using a Perkin-Elmer 2400 CHN elemental analyzer. All reactions were carried out under N2 or Ar.
Tetrahydrofuran (THF) and diethyl ether (Et2O) were freshly distilled from Na-benzophenone, n-hexane
was distilled over Na, and the other solvents were distilled over CaH2. Merck silica gel 60 was used for
the column chromatography.
Reaction of α-anion of 6a with MeI
~
Synthesis of [TBPY-5-12]-1-Ethyl-3,3,3',3'-
tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole] (9a).
Under N2, n-BuLi (1.56 M n-hexane solution, 0.24 mL, 0.37 mmol) was added to a mixture of 6a (250 mg,
0.34 mmol) and t-BuOK (1.0 M THF solution, 0.37 mL, 0.37 mmol) suspended in n-hexane (12 mL) at
0 °C. The mixture was then stirred for 1 h at rt. MeI (0.20 mL, 3.21 mmol) was added at 0 °C and the
mixture was again stirred for 1 h at rt. The mixture was extracted with ether (2 x 60 mL), and the brown
organic layer was washed with brine (2 x 40 mL) and dried over anhydrous MgSO4. After removing the
solvents by evaporation, the crude mixture was separated by column chromatography (CH2Cl2 : n-hexane
= 1 : 4), followed by reversed-phase HPLC (MeCN) to afford 9a (RT = 28.8 min.: 79.6 mg, 31%) as a
white solid. The colorless crystals of 9a suitable for X-ray analysis were obtained by recrystallization
from CH3CN: mp 98.7-99.3 °C (decomp);1H NMR (CDCl3) δ = 7.79-7.74 (m, 4H, aromatic), 7.64-7.57
2
3
3
3
(m, 4H, aromatic), 2.46 (dq, JH-P = 19, JH-H = 8 Hz, 2H, PCH2), 1.13 (dt, JH-P = 24, JH-H = 8 Hz, 3H,
CH3); 19F NMR (CDCl3) δ = –79.1 (s, 12F, CF2CF3), –115.6 (br s, 4F, CF2CF3), –116.3 (br s, 4F,
CF2CF3); 31P NMR (CDCl3) δ = –0.5; Anal. Calcd for C24H13F20O2P: C, 38.73; H, 1.76. Found: C, 39.05;
H, 1.71.
Reaction of α-anion of 6a with BrCF2CF2Br ~ Synthesis of [TBPY-5-11]-1-Bromomethyl-
3,3,3',3'-tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole] (10b).
To an α-anion prepared from 6a (29.7 mg, 0.040 mmol) by the above-described procedure was added
BrCF2CF2Br (0.02 mL, 0.16 mmol) at –78 °C. The mixture was stirred for 1 h at rt. The mixture was
extracted with ether (2 x 40 mL), and the brown organic layer was washed with brine (2 x 30 mL) and
dried over anhydrous MgSO4. After removing the solvents by evaporation, the resulting crude was

818
HETEROCYCLES, Vol. 73, 2007
separated by TLC (CH2Cl2 : n-hexane = 1 : 4) to afford 10b (16.5 mg, 50%) as a white solid. The
colorless crystals of 10b suitable for X-ray analysis were obtained by recrystallization from
CH2Cl2/n-hexane: mp 141.0-141.6 °C; 1H NMR (CDCl3) δ = 8.50-8.46 (m, 2H, aromatic), 7.78 (br s, 2H,
aromatic), 7.76-7.68 (m, 4H, aromatic), 3.65 (dd, 2JP-H = 6.6 Hz, 2JH-H = 11.2 Hz, 1H, PCH2Br), 3.54 (dd,
2JP-H = 6.6 Hz, 2JH-H = 11.2 Hz, 1H, PCH2Br); 19F NMR (CDCl3) δ = –78.4 (s, 6F, CF2CF3), –79.4 (dd, 3JF-F
= 19 Hz, 5JF-F = 6 Hz, 6F, CF2CF3), –116.4 (dq, 2JF-F = 287 Hz, 3JF-F = 19 Hz, 2F, CF2CF3), –116.6 (s, 2F,
CF2CF3), –116.7 (s, 2F, CF2CF3), –121.4 (dm, 2JF-F = 287 Hz, 2 F, CF2CF3); 31P NMR (CDCl3) δ = –22.7.
MS (EI(+)): m/z = 807 [M]+, 808 [M+1]+, 809 [M+2]+, 715 [M–CH2Br]+; Anal. Calcd for C23H10F20BrO2P:
C, 34.14; H, 1.25. Found: C, 34.35; H, 1.35.
Reaction of α-anion of 6a with ICH2CH2I ~ Synthesis of [TBPY-5-12]-1-Iodomethyl-
3,3,3',3'-tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole]
(9c)
and
[TBPY-5-11]-1-Iodomethyl-3,3,3',3'-tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphos-
phole] (10c).
To an α-anion prepared from 6a (183 mg, 0.251 mmol) by the above-described procedure was added
ICH2CH2I (284 mg, 1.0 mmol) at 0 °C. The mixture was stirred for 2 h at 0 °C. The mixture was extracted
with n-hexane cooled to 0 °C (2 x 60 mL), and the brown organic layer was washed with brine cooled to
0 °C (2 x 40 ml) and dried over anhydrous MgSO4. After filtering the organic layer through SiO2 and
removing the solvents by evaporation at 0 °C, the residue was separated by reversed-phase HPLC
(CH3CN) at rt to afford 9c (RT = 30.4 min.: 113 mg, 52%) and 10c (RT = 36.8 min.: 10.8 mg, 5%) as
white solids. The colorless crystals of 9c and 10c suitable for X-ray analysis were obtained by
1
recrystallization from n-hexane. 9c: mp 85.6-86.4 °C (decomp); H NMR (CDCl3) δ = 8.20 (br s, 2H,
19
aromatic), 7.78-7.59 (m, 6H, aromatic), 3.51 (br s, 2H, PCH2I); F NMR (CDCl3) δ = –79.1 (s, 12F,
31
CF2CF3), –115.1 (br s, 4F, CF2CF3), –115.9 (br s, 4F, CF2CF3); P NMR (CDCl3) δ = –8.0; Anal. Calcd
1
for C23H10F20IO2P: C, 32.27; H, 1.18. Found: C, 31.95; H, 1.14. 10c: mp 107.0-107.7 °C ; H NMR
(CDCl3) δ = 8.51-8.43 (m, 2H, aromatic), 7.80-7.72 (m, 6H, aromatic), 3.53 (dd, 2JH-P = 8, 2JH-H = 11 Hz,
1H, PCH2I), 3.37 (dd, 2JH-P = 4, 2JH-H = 11 Hz, 1H, PCH2I); 19F NMR (CDCl3) δ = –78.5 (s, 6F, CF2CF3),
3
–79.2 (dd, JF-F = 19.7 Hz, JF-F = 7.4 Hz, 6F, CF2CF3), –116.4 (dq, JF-F = 288 Hz, JF-F = 19.7 Hz, 2F,
5
2
3
2
5
CF2CF3), –116.4 (s, 2F, CF2CF3), –116.5 (s, 2F, CF2CF3), –121.3 (dq, JF-F = 288 Hz, JF-F = 7.4 Hz, 2F,
CF2CF3); 31P NMR (CDCl3) δ = –22.5; Anal. Calcd for C23H10F20IO2P: C, 32.27; H, 1.18. Found: C, 31.96;
H, 1.09.
Reaction of α-anion of 6a with PhSeBr ~ Synthesis of [TBPY-5-12]-1-Phenylselenomethyl-

HETEROCYCLES, Vol. 73, 2007
819
3,3,3',3'-tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole] (9d) and [TBPY-5-
11]-1-Phenylselenomethyl-3,3,3',3'-tetrakis(pentafluoroethyl)-1,1'-spirobi[3H,2,1,λ5-benzoxaphos-
phole] (10d).
To an α-anion prepared from 6a (102.8 mg, 0.141 mmol) by the above-described procedure was added
PhSeBr (129.6 mg, 0.538 mmol) at 0 °C. The mixture was stirred for 2.5 h at rt. The mixture was
extracted with Et2O (2 x 50 mL), and the brown organic layer was washed with brine (2 x 40 mL) and
dried over anhydrous MgSO4. After filtering the organic layer through SiO2 and removing the solvents by
evaporation, the residue was separated by reversed-phase HPLC (MeCN) to afford 9d (RT = 31 min.:
22.4 mg, 0.0253 mmol, 18%) and 10d (RT = 38.6 min.: 18.5 mg, 0.0208 mmol, 14%) as white solids. The
colorless crystals of 9d and 10d suitable for X-ray analysis were obtained by recrystallization from
n-hexane and CHCl3, respectively. 9d: mp 94.1-95.0 °C (decomp); 1H NMR (CDCl3) δ = 8.03 (t, 3JH-H = 8
3
Hz, 2H, aromatic), 7.75 (br d, JH-H = 8 Hz, 2H, aromatic), 7.64 (t, JH-H = 8 Hz, 2H, aromatic), 7.55 (d,
3
3
3JH-H = 8 Hz, 2H, aromatic), 7.51 (d, JH-H = 8 Hz, 2H, aromatic), 7.28-7.26 (m, 1H, aromatic), 7.19 (dd,
3
19
3JH-H = 8 Hz, 4JH-H = 2 Hz, 2H, aromatic), 3.64 (br d, JH-P = 11 Hz, 2H, PCH2Se); F NMR (CDCl3) δ =
31
–78.8 (s, 6F, CF2CF3), –79.0 (s, 6F, CF2CF3), –115.3 (br s, 4F, CF2CF3), –116.1 (br s, 4F, CF2CF3); P
1
NMR (CDCl3) δ = –6.3. 10d: mp 97.0-98.0 °C; H NMR (CDCl3) δ = 8.51 (m, 2H, aromatic), 7.76-7.71
2
(m, 6H, aromatic), 7.25-7.23 (m, 1H, aromatic), 7.16-7.10 (m, 4H, aromatic), 3.56 (dd, JH-P = 12, 2JH-H
=
12 Hz, 1H, PCH2Se), 3.29 (dd, 2JH-P = 8, 2JH-H = 12 Hz, 1H, PCH2Se); 19F NMR (CDCl3) δ = –78.5 (s, 6F,
CF2CF3), –79.3 (dd, 3JF-F = 19.9 Hz, 5JF-F = 7.5 Hz, 6F, CF2CF3), –116.5 (dq, 2JF-F = 288 Hz, 3JF-F = 19.9 Hz,
2F, CF2CF3), –116.6 (s, 2F, CF2CF3), –116.7 (s, 2F, CF2CF3), –121.3 (dq, 2JF-F = 288 Hz, 5JF-F = 7.5 Hz, 2F,
31
CF2CF3); P NMR (CDCl3) δ = –20.5; Anal. Calcd for C29H15F20O2PSe: C, 39.34; H, 1.71. Found: C,
39.42; H, 1.69.
Synthesis of O-equatorial 14 ([TBPY-5-12]-1-(2-Hydroxyethyl)-3,3,3',3'-tetrakis(pentafluoroethyl)-
1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole]).
To an α-anion prepared from 6a (374 mg, 0.513 mmol) by the above-described procedure was added
paraformaldehyde (64 mg, 2.0 mmol) at 0 °C. The mixture was stirred for 21 h at rt. The reaction was
quenched with aqueous NH4Cl (50 mL). The mixture was extracted with Et2O (2 x 80 mL), and the brown
organic layer was washed with brine (2 x 50 mL) and dried over anhydrous MgSO4. After filtering the
organic layer through SiO2 and removing the solvents by evaporation, the resulting crude mixture was
separated by reversed-phase HPLC (MeCN) to afford 14 (RT = 41 min.: 275 mg, 70%) as a white solid.
The colorless crystals of 14 suitable for X-ray analysis were obtained by recrystallization from
1
n-hexane/CH2Cl2: mp 112.0-112.9 °C (decomp); H NMR (CDCl3) δ = 7.78-7.74 (m, 4H, aromatic),
7.65-7.57 (m, 4H, aromatic), 3.89 (dt, 2JH-P = 17, 3JH-H = 8 Hz, 2H, PCH2), 2.75 (br s, 2H, PCH2CH2); F
19

820
HETEROCYCLES, Vol. 73, 2007
NMR (CDCl3) δ = –78.9 (s, 6F, CF2CF3), –79.4 (s, 6F, CF2CF3), –116.1 (br d, 2JF-F = 290 Hz, 4F, CF2CF3),
2 31
–117.4 (br d, JF-F = 290 Hz, 4F, CF2CF3); P NMR (CDCl3) δ = –2.8; Anal. Calcd for C24H13F20O3P: C,
37.91; H, 1.72. Found: C, 37.76; H, 1.77.
Synthesis of O-apical 15 ([TBPY-5-11]-1-(2-Hydroxyethyl)-3,3,3',3'-tetrakis(pentafluoroethyl)-
1,1'-spirobi[3H,2,1,λ5-benzoxaphosphole]).
To an α-anion prepared from 7a (118 mg, 0.162 mmol) by the above-described procedure was added
paraformaldehyde (29 mg, 0.91 mmol) at 0 °C. The mixture was stirred for 2 h at rt. The reaction was
quenched with aqueous NH4Cl (30 mL). The mixture was extracted with Et2O (2 x 50 mL), and the brown
organic layer was washed with brine (2 x 30 mL) and dried over anhydrous MgSO4. After filtering the
organic layer through SiO2 and removing the solvents by evaporation, the resulting crude mixture was
separated by reversed-phase HPLC (MeCN) to afford 15 (RT = 24 min.: 38.1 mg, 30%) as a white solid.
The colorless crystals of 15 suitable for X-ray analysis were obtained by recrystallization from n-hexane:
1
mp 146.6-147.6 °C; H NMR (CDCl3) δ = 8.46-8.41 (m, 2H, aromatic), 7.77-7.68 (m, 6H, aromatic),
3.91-3.87 (m, 1H, PCH2), 3.45-3.41 (m, 1H, PCH2), 2.51-2.42 (m, 2H, PCH2CH2); 19F NMR (CDCl3) δ =
5
2
–78.4 (s, 6F, CF2CF3), –79.5 (dd, 3JF-F = 19, JF-F = 6 Hz, 6F, CF2CF3), –116.4 (dq, JF-F = 290, 3JF-F = 19
2
2
Hz, 2F, CF2CF3), –117.2 (d, JF-F = 290 Hz, 4F, CF2CF3), –121.1 (dm, JF-F = 290 Hz, 2F, CF2CF3); P
31
NMR (CDCl3) δ = –21.5; Anal. Calcd for C24H13F20O3P: C, 37.91; H, 1.72; Found: C, 37.95; H, 1.71.
Synthesis of hexacoordinate phosphate 16.
A THF (0.6 mL) solution of 14 (12.2 mg, 0.016 mmol) and 18-crown-6 ether (7.5 mg, 0.028 mmol) was
added to a THF (0.6 mL) suspension of KH (excess), then the mixture was stirred for 10 min at 0 °C.
After removing the THF in vacuo, dry CD3CN (0.6 mL) was added. The solution was transferred to an
NMR tube under N2, and the NMR spectra of 16 were recorded. 1H NMR (CD3CN) δ = 8.05 (t, 3JH-H = 6.8
3
4
4
Hz, 1H, aromatic), 7.52 (tdd, JH-H = 6.8, JH-P = 2.4, JH-H = 1.2 Hz, 2H, aromatic) 7.35-7.40 (m, 2H,
aromatic), 7.12 (tdd, 3JH-H = 6.8, 4JH-P = 2.4, 3JH-H = 1.2 Hz, 1H, aromatic), 6.94 (dd, 3JH-P = 12.9, 3JH-H = 6.8
3
Hz, 1H, aromatic), 6.53 (dd, JH-P = 13.9, JH-H = 6.8 Hz, 1H, aromatic), 3.56 (br s, 24H, 18-crown-6),
3
19
3
3.35-3.42 (m, 2H, PCH2), 2.03-2.12 (m, 2H, PCH2CH2); F NMR (CD3CN) δ = –76.9 (br d, JF-F = 18.4
Hz, 3F, CF2CF3), –77.3 (br s, 3F, CF2CF3), –75.5 (br s, 3F, CF2CF3), –77.8 (dd, 3JF-F = 18.4, 5JF-F = 9.8 Hz,
3F, CF2CF3), –109.3 (d, 2JF-F = 290 Hz, 1F, CF2CF3), –109.5 (br d, 2JF-F = 290 Hz, 1F, CF2CF3), –112.6 (d,
2JF-F = 290 Hz, 1F, CF2CF3), –112.7 (d, 2JF-F = 290 Hz, 1F, CF2CF3), –113.2 (ddq, 2JF-F = 290, 4JF-F = 18.4,
2
2
3JF-F = 18.4 Hz, 1F, CF2CF3), –113.8 (dm, JF-F = 290 Hz, 1F, CF2CF3), –114.7 (dm, JF-F = 290 Hz, 1F,
CF2CF3), –114.9 (ddq, 2JF-F = 290, 4JF-F = 18.4, 5JF-F = 9.8 Hz, 1 F, CF2CF3); 31P NMR (CD3CN): δ = –98.2.

HETEROCYCLES, Vol. 73, 2007
821
Synthesis of hexacoordinate phosphate 17.
A THF (0.6 mL) solution of 15 (20.0 mg, 0.027 mmol) and 18-crown-6 ether (8.8 mg, 0.033 mmol) was
added to a THF (0.6 mL) suspension of KH (excess), then the mixture was stirred for 10 min at 0 °C.
After removing the THF in vacuo, dry CD3CN (0.6 mL) was added. The solution was transferred to an
3
NMR tube under N2, and the NMR spectra of 17 were recorded. 1H NMR (CD3CN) δ = 7.95 (dd, JH-P
=
3
12.4, JH-H = 7.2 Hz, 1H, aromatic), 7.75 (dd, JH-P = 12.9, JH-H = 7.2 Hz, 1H, aromatic), 7.45 (br s, 2H,
3
3
aromatic), 7.35-7.42 (m, 2H, aromatic), 7.24-7.29 (m, 2H, aromatic), 3.56 (br s, 24H, 18-crown-6),
19
3.13-3.25 (m, 2H, PCH2), 2.05-2.13 (m, 2H, PCH2CH2); F NMR (CD3CN) δ = –78.3 - –78.4 (m, 3F,
CF2CF3), –78.7 - –78.8 (m, 3F, CF2CF3), –79.3 - –79.4 (m, 3F, CF2CF3), –79.6 - –79.7 (m, 3F, CF2CF3),
–108.8 (d, 2JF-F = 290 Hz, 1F, CF2CF3), –109.4 (d, 2JF-F = 290 Hz, 1F, CF2CF3), –113.6 (dm, 2JF-F = 290 Hz,
4F, CF2CF3), –114.4 (d, 2JF-F = 290 Hz, 2F, CF2CF3); 31P NMR (CD3CN) δ = –105.2.
Synthesis of 15 from 14 under neutral conditions.
A C6D6 (0.5 mL) solution of 14 (14.0 mg, 0.0184 mmol) was heated at 80 °C for 9 h. After concentration
in vacuo, 15 was obtained (13.6 mg, 97%) as a white solid. The spectral data were consistent with those
of the product obtained in the synthesis of 15.
Synthesis of 14 from 15 under anionic conditions.
A THF (0.6 mL) solution of 15 (35.7 mg, 0.0469 mmol) and 18-crown-6 ether (12.4 mg, 0.0469 mmol)
was added to a THF (0.5 mL) suspension of KH (excess), then the mixture was stirred for 10 min at 0 °C.
The supernatant was transferred to an NMR tube under N2, and the mixture was heated for 8.5 h at 60 ˚C.
31
The reaction was monitored by P NMR. The mixture was treated with aqueous NH4Cl (10 mL). The
mixture was extracted with Et2O (2 × 20 mL) and the organic layer was washed with brine (2 × 20 mL)
and dried over anhydrous MgSO4. After removing the solvents by evaporation, the resulting crude was
separated by column chromatography (CH2Cl2 : n-hexane = 1 : 3) to afford 14 (27.7 mg, 77%) as a white
solid. The spectral data were consistent with those of the same product obtained as the product in the
synthesis of 14.
Single crystal X-ray analysis of 9a, 9c, 9d, 10b, 10c, 10d, 14 and 15.
Crystals suitable for the X-ray structural determination were mounted on a Mac Science DIP2030
imaging plate diffractometer and irradiated with graphite monochromated Mo-Kα radiation (λ = 0.71073
Å) for the data collection. The unit cell parameters were determined by separately autoindexing several
images in each data set using the DENZO program (MAC Science).16 For each data set, the rotation

822
HETEROCYCLES, Vol. 73, 2007
images were collected in 3 degree increments with a total rotation of 180 deg about the φ axis. The data
were processed using SCALEPACK. The structure was solved by a direct method with the SHELX-97
program.17 Refinement on F2 was carried out using the full-matrix leat-squares by the SHELX-97
program.17 All non-hydrogen atoms were refined using the anisotropic thermal parameters. The hydrogen
atoms were included in the refinement along with the isotropic thermal parameters. The crystallographic
data are summarized in Table 5.
CCDC-652179 (9a), 652180 (9c), 652181 (9d), 652182 (10b), 652183 (10c), 652184 (10d), 652185 (14)
and 652186 (15) contain the supplementary crystallographic data for this paper. These data can be
obtained free of charge from the Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
Table 5. Crystallographic data for 9a, 9c, 9d, 10b, 10c, 10d, 14 and 15.
Compound
Formula
Mol wt
9a
9c
9d
10b
C24H13F20O2P
744.31
monoclinic
P21/c
C23H10F20IO2P
856.18
C29H15F20O2PSe
885.34
C23H10F20BrO2P
809.19
Cryst syst
Space group
Color
monoclinic
P21/a
monoclinic
P21/c
orthorhombic
Pbcn
colorless
plate
colorless
plate
colorless
plate
colorless
plate
Habit
Cryst dimens, mm
a, Å
0.40 x 0.40 x 0.20 0.30 x 0.30 x 0.10 0.50 x 0.50 x 0.15 0.50 x 0.30 x 0.20
9.3210(2)
17.5280(3)
16.8660(4)
90
9.7040(3)
14.6860(5)
19.6440(8)
90
20.2180(3)
8.3780(10)
20.9830(6)
90
18.6030(8)
8.6890(2)
17.1930(6)
90
b, Å
c, Å
α, deg
β, deg
95.6980(10)
90
95.3130(10)
90
117.6400(10)
90
90
γ, deg
V, Å3
90
2741.93(10)
4
2787.50(17)
4
3148.62(11)
4
2779.10(17)
4
Z
Dcalc, g cm–3
Abs coeff, mm–1
F(000)
1.803
2.040
1.868
1.934
0.261
1.364
1.392
1.695
1472
1648
1736
1576
Radiation; λ, Å
Temp, K
Data, collcd
Data/restrains/param
R1 [I > 2σ(I)]
wR2 (all data)
GOF
Mo Kα, 0.71073
298(2)
Mo Kα, 0.71073
298(2)
Mo Kα, 0.71073
298(2)
Mo Kα, 0.71073
298(2)
+h, +k, +l
3111/0/218
0.0780
+h, +k, ±l
6080/0/425
0.0655
+h, +k, ±l
6177/0/424
0.0548
+h, +k, ±l
7007/0/478
0.0629
0.2275
0.2151
0.2117
0.2865
1.076
1.196
1.104
1.175
Solv for crystallization CH3CN
n-hexane
CH3CN
CH2Cl2/n-hexane

HETEROCYCLES, Vol. 73, 2007
823
14
15
Compound
Formula
Mol wt
10c
10d
C24H13F20O3P
760.31
C24H13F20O3P
760.31
monoclinic
P21/c
C23H10F20IO2P
856.18
triclinic
P–1
C29H15F20O2PSe
885.34
monoclinic
P21/c
Cryst syst
Space group
Color
monoclinic
P21/n
colorless
plate
colorless
plate
colorless
plate
colorless
plate
Habit
0.50 x 0.40 x 0.30 0.40 x 0.25 x 0.20
Cryst dimens, mm
a, Å
0.35 x 0.20 x 0.15 0.60 x 0.40 x 0.15
8.7220(2)
17.0420(3)
18.4890(3)
90
9.79100(10)
19.2970(4)
14.4780(4)
90
9.8110(2)
9.8770(3)
15.1740(5)
82.7890(10)
81.2620(10)
79.243(2)
1420.64(7)
2
13.2410(3)
13.4470(4)
18.9800(5)
90
b, Å
c, Å
α, deg
94.5790(10)
90
95.0350(10)
90
β, deg
107.6330(2)
90
γ, deg
V, Å3
2739.44(9)
4
2724.87(10)
4
3220.64(15)
4
Z
Dcalc, g cm–3
Abs coeff, mm–1
F(000)
2.002
1.826
1.843
1.853
0.266
0.267
1.338
1.361
1504
1504
824
1736
Mo Kα, 0.71073
298(2)
Mo Kα, 0.71073
298(2)
Radiation; λ, Å
Temp, K
Data, collcd
Data/restrains/param
R1 [I > 2σ(I)]
wR2 (all data)
GOF
Mo Kα, 0.71073
298(2)
Mo Kα, 0.71073
298(2)
+h, +k, ±l
6530/0/434
0.0467
+h, +k, ±l
6227/0/434
0.0458
+h, ±k, ±l
6047/0/424
0.0497
+h, +k, ±l
7520/0/478
0.0734
0.1716
0.1313
0.1561
0.2348
1.154
1.019
1.098
1.144
CH2Cl2/n-hexane
n-hexane
Solv for crystallization n-hexane
CHCl3
ACKNOWLEDGEMENTS
This work was supported by two Grants-in-Aid for Scientific Research on Priority Areas (Nos. 14340199,
17350021) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
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