The first structural study on a cyclic tricoordinate phosphorochloridite and a pentacoordinate phosphorane based on 1,2,3,5-protected myo-inositol-a new conformation of 1,3,2-dioxaphosphorinane ring

Article abstract of DOI:10.1016/j.carres.2007.02.031

Treatment of the phosphoramidite {myo-C₆H₆-2-[OC(O)Ph]-1,3,5-(O₃CH)-4,6-(O₂P-NH-i-Pr)} with o-chloranil affords the first example of inositol-based pentacoordinate phosphorane {myo-C₆H₆-2-[

Full text of DOI:10.1016/j.carres.2007.02.031

Carbohydrate Research 342 (2007) 1182–1188
The first structural study on a cyclic tricoordinate
phosphorochloridite and a pentacoordinate phosphorane based
on 1,2,3,5-protected myo-inositol—a new conformation of
1,3,2-dioxaphosphorinane ring
K. V. P. Pavan Kumar and K. C. Kumara Swamy*
School of Chemistry, University of Hyderabad, Hyderabad 500 046, AP, India
Received 4 December 2006; received in revised form 23 February 2007; accepted 23 February 2007
Available online 1 March 2007
Abstract—Treatment of the phosphoramidite {myo-C6H6-2-[OC(O)Ph]-1,3,5-(O3CH)-4,6-(O2P-NH-i-Pr)} with o-chloranil affords
the first example of inositol-based pentacoordinate phosphorane {myo-C6H6-2-[OC(O)Ph]-1,3,5-(O3CH)-4,6-(O2P-NH-i-Pr)(1,2-
O2C6Cl4)} (9) (X-ray structure) with a trigonal bipyramidal geometry at phosphorus. The six-membered 1,3,2-dioxaphosphorinane
ring with the inositol residue has an unusual boat conformation in 9 which is quite different from that found in unrestrained rings
investigated before, but is similar to that of its PIII chloro precursor {myo-C6H6-2-[OC(O)Ph]-1,3,5-(O3CH)-4,6-(O2PCl)} (X-ray
structure). Also, a convenient and chromatography-free procedure for the protected myo-inositol derivative {myo-C6H6-2-
[OC(O)Ph]-1,3,5-(O3CH)-4,6-(OH)2} is reported.
ꢀ 2007 Elsevier Ltd. All rights reserved.
Keywords: myo-Inositol; Conformation; Phosphoranes; Pentacoordinate; X-ray structure
1. Introduction
mechanism for the phosphatidylinositol cleavage cata-
lyzed by phosphatidylinositol-specific phospholipase
(PI-PLC) also takes place via a pentacoordinate transi-
tion state species (3, Chart 1).7
Phosphorus, in the form of either a phosphate or a phos-
phonate is ubiquitous in nature, and c-AMP, inositol
phosphates, RNA, and alkylphosphonic acids represent
a few examples wherein it exhibits a significant role in
metabolic processes.1 Several partially substituted myo-
inositol (1) phosphates with the phosphate at (1,3,4,5)-,
(1,2,4,5,6)-, (1,2,3,5,6)-, (1,3,4)-positions occur in nat-
ure, in addition to 1D-myo-inositol 1,4,5-trisphosphate
[Ins(1,4,5)P3] (2) which acts as a second messenger in
linking the spatially separated events of receptor simula-
tion and release of intramolecular calcium from internal
stores.2–6 All these derivatives therefore have significant
therapeutic potential and hence developing new syn-
thetic routes to them may be beneficial. The proposed
In the above context, the structural characterization of
biologically relevant amino acid and thymidine based
phosphoranes 4 and 5 are of some significance.8,9 Also,
in the metabolic reactions involving cyclic adenosine
monophosphate (c-AMP), featuring a saturated 1,3,2-
dioxaphosphorinane ring, it is not clearly known whether
in the transition state the six-membered ring assumes a
diequatorial e–e or a–e disposition or if the conformation
is enzyme dependent.10 Studies on a large number of neu-
tral pentacoordinate compounds during 1990’s revealed
that in a majority of cases similar rings assume an a–e
disposition with a boat conformation (I).11–13 By con-
trast, such a ring in the precursor P(III) compounds
adapts a chair conformation of type II.13–16 Thus there
is interest in pentacoordinate phosphorus compounds
formed with biologically relevant molecules17 and this
*
Corresponding author. Tel.: +91 40 23134856; fax: +91 40
23012460; e-mail: kckssc@uohyd.ernet.in
0008-6215/$ - see front matter ꢀ 2007 Elsevier Ltd. All rights reserved.
doi:10.1016/j.carres.2007.02.031

K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
1183
OH
OH
OH
OH
OH
2
OH
2
4
OH
1
O3PO
5
HO
HO
6
6
2
2
3
OPO3
O3PO
HO
3
OH
HO
5
2
HO
4
1
HO
2
1
OH
1D-myo-inositol 1,4,5-trisphosphate
myo-inositol
Arg-69
N
H2N
+
NH
His-82
H
N
O
O
O
N
Asp-33
H
O
O
R
P
O
O
Asp-274
O
O
H
H
N
''''''''''''''
N
OH
OH
OH
His-32
HO
Transition state proposed for the phosphatidylinositol cleavage by PI-PLC
3
Chart 1.
is a subject in which we have been interested.18–20 We
were interested in systems with the (1,3,5) positions
blocked so that (4,6) positions can be effectively utilized
for phosphorylation. In doing so, we were curious to see
whether the generally observed structural features of
1,3,2-dioxaphosphorinane systems are seen in such com-
pounds or not. Although we are not aware of reports on
such cyclic inositol phosphates in biosystems, it is possi-
ble that they may have some role as transition state
species in metabolic processes. Herein we report a
chromatography-free synthesis of 2-benzoylated 1,3,5-
protected inositol (6), and structural features of some
of its phosphorus (tri- and penta-coordinate) derivatives.
2. Results and discussion
The monobenzoylated inositol diol 6 was prepared by a
modification of the literature procedure,21 which used
column chromatography for purification of the com-
H
O
N
O
N
O
O
P
O
H
P
O
O
O
O
H
O
Me
O
N
H
N
H3C
CH3
F
H
5
4
C
(apical in TBP)
O
C
P
O
C
C
C
C
O
(equatorial in TBP)
O
P
(II)
(I)
O
O
1
O
5
6
BzO
3
2
4
HO
6
OH

1184
K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
OH
OH
CH(OEt)3
OH
O
1
O
5
O
O
6
O
C6H5C(O)Cl
Pyridine
4-Me-C6H4-SO3H (cat)
O
(i)
HO
3
DMF, 100 oC
HO
2
4
HO
BzO
HO
O
OH
HO
myo-inositol
OH
OH
6
O
O
O
O
O
O
PCl3
Neat
O
2 H2N-
i-Pr
O
(ii)
+
BzO
BzO
- [H3N-
i-Pr][Cl]
BzO
-2HCl
O
HO
O
O
7 [δ(P): 140.0]
OH
O
P
Cl
P
NH-
i-Pr
8 [δ(P): 140.6]
6
Scheme 1.
pound. In our case, after removal of most of the pyri-
dine [Scheme 1i], ethyl acetate was added; the organic
layer was washed with dilute hydrochloric acid (to
remove traces of pyridine) and solvent removed
completely. Upon addition of dichloromethane, the
monobenzoylated compound 6 crashed out, leaving
behind the dibenzoylated derivative in soln. Thus the
tedious column chromatography is avoided. This
compound was then reacted with PCl3 under neat condi-
tion to lead to the phosphorochloridite 7 in good yield.
Further treatment of 7 with isopropylamine gave the
corresponding phosphoramidite 8 [Scheme 1ii]. It is pos-
sible that the orientation of the NH-i-Pr group is oppo-
site to that of chlorine in 7, but we have not studied this
aspect in the current study.
six-membered 1,3,2-dioxaphosphorinane rings with
phosphorus in tri-, tetra-, penta- or hexa-coordinate
state.13,22–26 We succeeded in getting the crystals of 7,
but not of 8.
The X-ray structure of 7 (Fig. 1) clearly shows that the
six membered 1,3,2-dioxaphosphorinane ring containing
phosphorus adapts a boat conformation with the phos-
phorus and C(5) atoms above the mean plane containing
˚
the other four atoms in the ring by 0.391 and 0.695 A,
respectively. This is quite interesting because for the pre-
viously determined structures containing unconstrained
phosphorinane rings,
a
chair conformation was
found.13–16,22–25 The unusual boat conformation found
in 7 is probably formed because in the chair conforma-
tion the phosphorus (or chlorine) may have unfavorable
steric interactions with O(7) or C(2)–H (see Fig. 1).
Although not investigated herein, it is interesting to note
that the molecule crystallizes in the chiral space group
P21 and the structure determined shows C(1) and C(3)
having the configuration (S) and (R), respectively. In
soln, there was no observable optical rotation.
The 1H, 13C, and 31P NMR spectra are consistent with
the structure as written; in its 13C NMR spectrum
(1100 MHz), 7 exhibits a total of six peaks in the region
d 60–70 for the inositol ring carbons. Since these com-
pounds constitute the first examples of inositol based
cyclic phosphites, we were curious to look at the confor-
mational features of this compound vis-a-vis the penta-
coordinate derivatives (vide infra). Also, we have been
interested in learning about the conformation of the
That the 1,3,2-dioxaphosphorinane ring system pre-
pared from the protected inositol diol 6 has a different
conformation compared to the unrestrained ones is also
C13
C7
C12
C11
O3
C3
O5
Cl
O1
C4
C14
C5
O2
C8
C9
C1
O4
C5
C2
C6
O6
C10
O4
O6
C4
Cl
O7
P
C6
P
Figure 1. Left: Molecular structure of 7 showing the numbering scheme on selected atoms. Right: Drawing showing the conformation of the
˚
phosphorinane ring. Selected bond parameters: P–O(4) 1.6127(16), P–O(6) 1.6024(16), P–Cl 2.1227(9) A, O(4)–P–O(6) 102.12(8), O(4)–P–Cl
100.72(7), O(6)–P–Cl 100.38(6)ꢁ.

K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
1185
shown by the structure of a cyclic inositol phosphate as
C13
C12
C11
C7
O1
C4
O3
C3
a trihydrate of its potassium-18-crown-6 salt, viz. [K-
(18-crown-6)]+{myo-C6H6-2-[OC(O)Ph]-1,3,5-(O3CH)-
[O2P(O)O]}ꢀÆ3H2O (10) reported previously from our
laboratory.26
C14
C8
O7
O5
C5
O2
C9
C10
C1
O4
C2
C6
O6
O9
Cl4
C22
P
O
O
O
O
C15
C17
C23
O
O
O
O
C16
+
Cl3
C21
PhOCO
.3H2O
O8
N
K
C18
Cl1
O
O
O
C20
O
O P
C19
Cl2
10
Figure 2. Molecular structure of 9ÆCH2Cl2 showing all non-hydrogen
atoms. The symmetry (inversion) related molecule in the unit cell is not
shown. Solvent molecule is also not shown. Selected bond parameters
We treated the protected inositol phosphite 7 with
diisopropyl azodicarboxylate (DIAD) as well as o-
chloranil at room temperature, but there was no appar-
ent reaction in either case [31P NMR]. Then we reacted 8
with o-chloranil (which is more reactive) and obtained
the pentacoordinate phosphorane 9 (Scheme 2). Com-
pound 9 is the first example of a pentacoordinate phos-
phorus compound with the inositol residue. Its 31P
NMR spectrum shows a peak at d ꢀ53.1 consistent with
pentacoordination in soln.13,19,20,27–32
The molecular structure of 9ÆCH2Cl2 along with the
bond parameters is shown in Figure 2. The more electro-
negative oxygen atoms occupy the apical positions while
the less electronegative nitrogen is equatorial in the tri-
gonal bipyramidal (TBP) structure, as expected from
Bent’s rule.33 The P–O bond distances for apical substit-
uents in TBP structures are expected to be longer than
the equatorial ones. In compound 9, one of the P–O(api-
˚
(A, ꢁ): P–O(4) 1.6306(14), P–O(6) 1.5985(15), P–O(8) 1.7907(15), P–
O(9) 1.6546(15), P–N 1.616(2); O(4)–P–O(6) 98.84(7), O(4)–P–O(8)
176.50(8), O(4)–P–O(9) 89.44(7), O(4)–P–N 92.27(9), O(6)–P–O(8)
84.64(8), O(6)–P–O(9) 112.46(8), O(6)–P–N 121.18(9), O(8)–P–O(9)
88.87(7), O(8)–P–N 86.20(9), O(9)–P–N 125.30(10).
bonds in pentacoordinate phosphorus.34 Although this
feature has been observed before, a satisfactory bonding
model has not emerged so far. The sum of the bond
angles at nitrogen is 357.6ꢁ, suggesting that it is
essentially planar.
The six-membered ring in 9, which is more rigid be-
cause of the adamantane moiety of the inositol residue,
has a boat conformation [Fig. 3a] slightly flattened at the
phosphorus end. This is in line with that observed for
several other pentacoordinate compounds with 1,3,2-
dioxaphosphorinane ring (Fig. 3b).13 However, it should
be noted that in those cases, the precursor PIII com-
pound had a chair conformation (e.g., 1113) while our
inositol derived PIII compound 7 has a boat conforma-
tion (discussed above). A more important point of inter-
est is that the observed boat conformation in 9 [Fig. 3a]
is actually different from that observed in other pentaco-
ordinate compounds in that for the latter, one oxygen
and a CH2 carbon are above the mean plane of the other
four atoms (e.g., 12;13 Fig. 3b). In 9, the phosphorus and
˚
˚
cal) bonds [P–O(4) 1.6306(14) A] is actually 0.02 A
shorter than P–O(equatorial) bonds [P–O(9)
˚
1.6546(15) A]. Although one can say that O(4) is con-
nected to an aliphatic residue and O(9) belongs to a 5-
membered catecholate residue, the fact remains that api-
cal one is shorter. Why is it that apical P–O(4) bond is
shorter than even the equatorial P–O(9) bond is not sat-
isfactorily explained by the 3c–4e model for the apical
O
O
BzO
O
O
O
Cl
O
O
O
Cl
Cl
Toluene, rt
12 h
O
BzO
+
O
i-Pr
-HN
P
O
O
Cl
O
Cl
NH-
i-Pr
P
O
Cl
Cl
8 [δ(P): 140.6]
9 [δ(P): -53.1]
Cl
Scheme 2.

1186
K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
Figure 3. Plots showing the conformation of the six-membered ring in (a) compound 9 and (b) other pentacoordinate compounds (e.g., 12) with
apical–equatorial disposition of the ring.
a carbon atom of the inositol residue are above the mean
plane of the remaining four atoms.
were recorded on a JASCO FT/IR 5300 FT-IR
spectrometer. Melting points were determined by using
a local hot-stage melting point apparatus and are
uncorrected. Microanalyses were performed using a
Thermo Finnigan EA1112 analyzer.
O
O
O
O
P
NHC6H11
P
NHC6H11
O
3.1. Preparation of 8,9-dihydroxy-6-phenylcarbonyloxy-
2,4,10-trioxa-tricyclo[3.3.1.13,7]decane (6): modified
procedure
O
Cl
Cl
Cl 12
11
Cl
Myo-inositol (2.70 g, 15.0 mmol), triethylorthoformate
(2.40 g, 22.5 mmol), p-toluenesulfonic acid monohydrate
(0.25 g, 1.31 mmol) and dry DMF (20 mL) were mixed
and heated at 100 ꢁC with stirring for 3 h. The clear soln
was cooled to room temperature. Then triethylamine
(1.0 mL) was added to the mixture and low boiling com-
ponents were removed under diminished pressure. Dry
toluene was added and the solvent again removed under
diminished pressure (2 · 5 mL). This operation was use-
ful in removing traces of DMF. The residue was cooled
to 0 ꢁC and then pyridine (10 mL) followed by benzoyl
chloride (2.20 g, 15.0 mmol) were added drop-wise over
a period of 30 min. The reaction mixture was brought
to room temperature and stirred for 8 h. After removal
of most of the pyridine, ethyl acetate was added; the or-
ganic layer was washed with dil HCl (to remove traces
of pyridine) and solvent removed completely. Upon addi-
tion of dichloromethane, the monobenzoylated com-
pound 6 precipitated out. Yield: 0.22 g (50%). [Mp:
206–208 ꢁC; lit. 209 ꢁC;21 1H NMR (Me2SO-d6
(0.3 mL)-CD3OD (0.1 mL), 400 MHz): d 7.46–8.05 (m,
5H, Ar-H), 5.69 (br s, 2H, –OH), 5.49 and 5.52 (2 br s,
2H, inositol-H), 4.41 (br s, 2H, inositol-H), 4.28 (br s,
1H, inositol-H), 4.19 (br s, 1H, inositol-H)]. We did not
observe any optical rotation for this compound in soln.
The extent of distortion from TBP to square pyrami-
dal (SQP) or tetragonal pyramidal (RP) geometry in 9 is
calculated by the dihedral angle method of Holmes35
and this value is 15.4% TBP!SQP (RP). Thus, for all
practical purposes, phosphorus in compound 9 can be
considered to be having trigonal bipyramidal geometry.
2.1. Summary
To summarize, we have provided a convenient chroma-
tography-free synthesis of the 1,2,3,5-protected inositol
that could be utilized as a convenient 4,6-diol. X-ray
structures of the first examples of a cyclic phosphite
(7) and a pentacoordinate phosphorane (9) based on this
protected inositol are reported. The 1,3,2-dioxaphos-
phorinane ring in these compounds adopts a boat con-
formation, which is different from those normally
observed for other analogous dioxaphosphorinane rings
that exhibit either a chair conformation or a boat form
different from that observed here.
3. Experimental
Chemicals were purchased from Aldrich or local manu-
facturers; they were purified when required according to
standard procedures.36 All reactions, unless stated
otherwise, were performed in a dry nitrogen atmo-
sphere. 1H, 13C, and 31P{H} NMR spectra were re-
corded using a 200 or a 400 MHz spectrometer in
CDCl3 (unless stated otherwise) with shifts referenced
to SiMe4 (d = 0) or 85% H3PO4 (d = 0). Infrared spectra
3.2. 4-Chloro-12-phenylcarbonyloxy-3,5,8,10,13-penta-
oxa-4-phosphatetracyclo[7.3.1.02,7.06,11]tridecane (7)
An excess of phosphorus trichloride (20 mL) was added
to 6 (1.20 g, 4.08 mmol) and the mixture heated under
reflux for 1 d. Unreacted phosphorus trichloride was re-
moved by distillation to obtain a white solid. This was
crystallized from toluene to give 7. Yield 1.16 g (80%).

K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
1187
Mp: 130–132 ꢁC. IR (KBr): 1726, 1603, 1454, 1408,
1277, 1165 cmꢀ1 1H NMR (CDCl3, 400 MHz): d
(br s, 1H, NH), 3.21 (m, 1H, NHCH(CH3)2), 1.23 (br
s, 6H, NHCH(CH3)2); 13C NMR (CDCl3, 100 MHz):
d 165.7 (s, Ph–C(O)O–),133.5, 129.9, 129.2, 128.9,
128.4, 128.1, 127.9, 127.8, 127.4, 125.2, 101.9 (s,
O3CH), 70.0, 63.4, 61.7, 61.5, 47.3 (s, NCH(CH3)2),
20.8 and 21.3 (2 s, NCH(CH3)2); 31P NMR (CDCl3,
160 MHz): d ꢀ53.1; Anal. calcd for C23H20Cl4NO9P:
C, 44.05; H, 3.21; N, 2.23. Found: C, 44.09; H, 3.25;
N, 2.38. We did not observe any optical rotation for this
compound in soln.
;
7.45–8.18 (m, 5H, Ar-H), 5.75 (s, 1H, O3CH), 5.62 (m,
1H, inositol-H), 5.46 (m, 1H, inositol-H), 5.23 (m, 2H,
inositol-H), 4.61 (m, 2H, inositol-H); 13C NMR (CDCl3,
100 MHz): d 165.8 (Ph–C(O)O–), 133.7, 130.0, 129.2,
129.0, 128.6, 128.2, 102.2, 69.0, 68.9, 68.8, 63.3, 61.1,
60.9; 31P NMR (CDCl3, 160 MHz): d 140.0. Anal. calcd
for C14H12ClO7P: C, 46.88; H, 3.37. Found: C, 46.79; H,
3.37. We did not observe any optical rotation for this
compound in soln.
X-ray crystallography: Single crystal X-ray data were
collected on a Bruker AXS-SMART diffractometer,
˚
3.3. 4-Isopropylamino-12-phenylcarbonyloxy-3,5,8,10,13-
pentaoxa-4-phosphatetracyclo[7.3.1.02,7.06,11]tridecane
(8)
using Mo-Ka (k = 0.71073 A) radiation. The structures
were solved by direct methods and refined by full-matrix
least squares method using standard procedures.37 All
non-hydrogen atoms were refined anisotropically;
hydrogen atoms were fixed by geometry using a riding
model.
To a stirred soln of 7 (0.60 g, 1.60 mmol) in toluene
(20 mL) at room temperature (25 ꢁC) was added isopro-
pylamine (0.20 g, 3.30 mmol) drop-wise over a period of
10 min. After stirring for 12 h, filtration followed by the
removal of solvent afforded 8 as a white solid. Yield:
0.52 g (82%); mp: 114–116 ꢁC; IR (KBr): 3414, 1620,
Crystal data for 7: C14H12ClO7P, Mr = 358.66, mono-
˚
clinic, space group P21, a = 7.4207(8) A, b =
˚
3
˚
10.9150(12) A, c = 9.2807(10) A, b = 100.854(2), V =
˚
738.26(14) A , Z = 2,
q
calcd = 1.613 Mg mꢀ3
,
l =
1408, 1167 cmꢀ1
;
1H NMR (CDCl3, 400 MHz): d
0.402 mmꢀ1
,
F(000) = 368,
Flack
data/restraints/para-
7.48–8.20 (m, 5H, Ar-H), 5.93 (m, 1H, O3CH), 5.56
(m, 1H, inositol-H), 5.18 (m, 1H, inositol-H), 5.07 (m,
2H, inositol-H), 4.50 (m, 2H, inositol-H), 3.79 (br s,
1H, NH), 2.87 (m, 1H, NHCH(CH3)2), 1.22 (d, 6H,
3JH–H = 6.2 Hz, NHCH(CH3)2); 13C NMR (CDCl3,
100 MHz): d 166.0 (Ph–C(O)O–), 133.4, 130.0, 129.6,
129.0, 128.5, 128.2, 102.6 (O3CH), 70.0, 68.9, 64.8,
meters = 3393/1/208.
[absolute configuration at C(1) is S and at C(3) is R],
parameter = ꢀ0.01(6)
R
indices (I > 2r(I)): R1 = 0.0326, wR2 = 0.0819,
GOF = 1.046, max./min. residual electron density
ꢀ3
˚
0.284/ꢀ0.222 eA
.
Crystal data for 9ÆCH2Cl2: C24H22Cl6NO9P,
Mr = 712.10, triclinic, space group P1, a =
9.8167(8) A, b = 10.2887(9) A, c = 15.3489(13) A, a =
89.190(1), b = 83.788(1), c = 72.999(1)ꢁ, V =
1473.6(2) A , Z = 2, qcalcd = 1.605 Mg mꢀ3, l = 0.689
mmꢀ1
F(000) = 724, data/restraints/parameters =
ꢀ
2
˚
˚
˚
64.4, 64.1, 42.0 (d, JP–C = 12.0 Hz, PNHC(CH3)2),
3
26.7 (d, JP–C = 4.0 Hz, PNCH(CH3)2); 31P NMR
3
˚
(CDCl3, 160 MHz):
d
140.6; Anal. calcd for
C17H20NO7P: C, 53.55; H, 5.29; N, 3.67. Found: C,
53.59; H, 5.28; N, 3.75. We did not observe any optical
rotation for this compound in soln.
,
6868/0/376, R indices (I > 2r(I)): R1 = 0.0432, wR2 =
0.1230, GOF = 1.054, max./min. residual electron
ꢀ3
˚
density 0.408/ꢀ0.300 e A
.
3.4. Synthesis of dichloromethane solvate of the
o-chloranil adduct of 4-isopropylamino-12-phenylcarbon-
yloxy-3,5,8,10,13-pentaoxa-4-phosphatetracyclo-
[7.3.1.02,7.06,11]tridecane {myo-C6H6-2-[OC(O)Ph]-1,3,5-
(O3CH)-4,6-{O2P[NHCH(CH3)2][1,2-
4. Supplementary data
Complete crystallographic data for the structural analy-
sis have been deposited with the Cambridge Crystallo-
graphic Data Centre, CCDC nos. 629164 and 629165.
Copies of this information may be obtained free of
charge from the Director, Cambridge Crystallographic
Data Centre, 12 Union Road, Cambridge, CB2 1EZ,
UK (fax: +44 1223 336033, e-mail: deposit@ccdc.cam.
ac.uk or via: www.ccdc.cam.ac.uk).
O2C6Cl4]}ÆCH2Cl2} (9)
To a soln of 8 (0.40 g, 1.04 mmol) in toluene (10 mL), o-
chloranil (0.25 g, 1.04 mmol) was added and the soln
heated at 50–60 ꢁC for 10 min. Later the reaction mix-
ture was allowed to come to room temperature and stir-
red overnight. The solvent was removed and the residue
crystallized from dichloromethane and traces of hexane.
Yield: 0.46 g (70%); mp: 150–152 ꢁC; IR (KBr): 3383,
1
1726, 1232, 1107 cmꢀ1; H NMR (after drying for 2 h
Acknowledgements
in vacuum) (CDCl3, 400 MHz): d 7.50–8.19 (m, 5H,
Ar-H), 5.71 (br s, 1H, O3CH), 5.58 (br s, 1H, inositol-
H), 5.30 (s, CH2Cl2), 5.03 (br s, 2H, inositol-H), 4.82
(br s, 1 H, inositol-H), 4.63 (br s, 2H, inositol-H), 3.84
We thank the Council of Scientific and Industrial
research (CSIR, New Delhi), for financial support.
K.V.P.P.K. also thanks CSIR, for a fellowship. The

1188
K. V. P. Pavan Kumar, K. C. Kumara Swamy / Carbohydrate Research 342 (2007) 1182–1188
Quin, L. D., Eds.; Deerfield Beach: VCH, 1987; Chapter
11, pp 365–389.
17. Timosheva, N. V.; Chandrasekaran, A.; Holmes, R. R.
Inorg. Chem. 2006, 45, 10836–10848.
18. Kumara Swamy, K. C.; Satish Kumar, N. Acc. Chem. Res.
2006, 39, 324–333.
National Single Crystal Diffractometer Facility at the
University of Hyderabad funded by DST (New Delhi)
as well as CAS and UPE programmes of the UGC are
also gratefully acknowledged.
19. Kommana, P.; Kumaraswamy, S.; Vittal, J. J.; Kumara
Swamy, K. C. Inorg. Chem. 2002, 41, 2356–2363.
20. Pavan Kumar, K. V. P.; Satish Kumar, N.; Kumara
Swamy, K. C. New J. Chem. 2006, 30, 717–728.
21. Samanta, U.; Puranik, V. G.; Chakrabarti, P.; Thoniyot,
P.; Shashidhar, M. S. Acta Cryst. 1998, C54, 1289–
1291.
22. Said, M. A.; Kumara Swamy, K. C.; Irmer, R.-H.;
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