Synthesis of phosphorus- and selenium-containing macrocycles and their complexation with Pd(II)Cl2

Article abstract of DOI:10.1039/b005045h

A one-pot reaction was developed to synthesize phosphorus- and selenium-containing macrocycles starting from selenium via reduction with KBH₄, treatment with bis[o-(bromomethyl)phenyl]phenylphosphine oxide 1 and reduction with KBH₄ followed by the addition of an appropriate dibromide. Thus, ten-to seventeen-membered macrocycles 3 having one phosphorus and two selenium atoms were synthesized. In this synthesis an eight-membered heterocycle 4 was also obtained. In addition, the condensation of compound 1 with selenium-containing diols 7 and 8 in the presence of sodium tert-butoxide gave macrocyclic ligands 9 and 10, respectively. Reaction of these macrocycles with palladium(n) chloride gave 1: 1 complexes, except 9 which gave a 2: 1 complex. The molecular structures of the macrocycles 3c, 3f and 10 as well as the 2: 1 palladium(II) complex 21 of related 2-(p-methyl-phenoxy)-2-oxo-1,3,6,2-dioxaselenaphosphocane 20 have been established by X-ray diffraction.

Full text of DOI:10.1039/b005045h

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Synthesis of phosphorus- and selenium-containing macrocycles and
their complexation with Pd(II)Cl2
J. L. Li, J. B. Meng,* Y. M. Wang, J. T. Wang and T. Matsuura
1
Department of Chemistry, Nankai University, Tianjin, 300071, China
Received (in Cambridge, UK) 23rd June 2000, Accepted 5th March 2001
First published as an Advance Article on the web 5th April 2001
A one-pot reaction was developed to synthesize phosphorus- and selenium-containing macrocycles starting from
selenium via reduction with KBH4, treatment with bis[o-(bromomethyl)phenyl]phenylphosphine oxide 1 and
reduction with KBH4 followed by the addition of an appropriate dibromide. Thus, ten- to seventeen-membered
macrocycles 3 having one phosphorus and two selenium atoms were synthesized. In this synthesis an eight-membered
heterocycle 4 was also obtained. In addition, the condensation of compound 1 with selenium-containing diols 7
and 8 in the presence of sodium tert-butoxide gave macrocyclic ligands 9 and 10, respectively. Reaction of these
macrocycles with palladium() chloride gave 1 : 1 complexes, except 9 which gave a 2 : 1 complex. The molecular
structures of the macrocycles 3c, 3f and 10 as well as the 2 : 1 palladium() complex 21 of related 2-(p-methyl-
phenoxy)-2-oxo-1,3,6,2-dioxaselenaphosphocane 20 have been established by X-ray diffraction.
The chemistry of phosphorus-containing macrocycles as well as
that of selenium-containing macrocycles has attracted great
attention in recent years.1–4 To the best of our knowledge, the
simultaneous introduction of phosphorus and selenium atoms
into the ring system of macrocycles has not been reported.
Phosphine oxides have been demonstrated to serve as strong
hydrogen-bond acceptors and good ligands for alkali,5 alkaline-
earth6 and actinide7 metal salts and selenium-containing
macrocycles4 exhibit excellent ligands for transition metals
owing to the low electronegativity of selenium. Thus macro-
cycles incorporating a hard phosphine oxide group and soft
selenium atoms into the ring system may act as potential
heterodinucleating macrocyclic ligands, which will be used
for future studies of bimetallic catalysis and formation of
supramolecular systems.8,9
In our preliminary work, we have reported the synthesis of
medium-sized heterocycles incorporating a phosphoryl group
and a selenium atom in the ring.10 Here, we report the synthesis
of a series of macrocycles incorporating a phosphine oxide
group and selenium atoms into the cycle. Complexation of
these macrocycles with palladium chloride as well as the X-ray
structure determination of macrocycles 3c, 3f, 10 and a related
palladium complex 21 has also been investigated.
Results and discussion
Synthesis of the P- and Se-containing macrocycles
A facile synthetic method for a series of macrocycles containing
a phosphine oxide group and selenium atoms was developed.
Macrocycles 3a, 3c–3l were obtained by a one-pot reaction
Scheme 1
a
as shown in Scheme 1. Pulverized selenium metal was reduced
with potassium borohydride in absolute alcohol to produce
potassium diselenide which reacted with bis[o-(bromomethyl)-
phenyl]phenylphosphine oxide 1 to give an intermediate,
13-phenyl-7,13-dihydro-5H-13λ5-dibenzo[d,g][1,2,6]diselena-
phosphonin-13-one 2. Without isolating 2, the mixture was
treated with potassium borohydride and sodium hydroxide to
form a diselenide anion 2Ј, which was allowed to react with
various α,ω-dibromides (Br–R–Br) to give macrocycles 3 via an
intermediate 2Ј. The yield of this one-pot reaction was moder-
ate as shown in Table 1. In every case a side product, 12-phenyl-
7,12-dihydro-5H-12λ5-dibenzo[c,f][1,5]selenaphosphocin-12-one
Table 1 Yields (%) of compounds 3a–k and 4
a
b
c
d
e
f
g
h
i
j
k
l
3
4
24
0
22 25 12 19 30 21
25.6 16 35 15
nd nd nd 23 44 33 37
7.3 8.6 14 nd nd
a nd: not determined.
4 was inevitably formed (Table 1). The formation of heterocycle
4 might occur along either of two routes (Scheme 1): one involv-
ing the reaction of 1 with potassium selenide which was formed
1140
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146
This journal is © The Royal Society of Chemistry 2001
DOI: 10.1039/b005045h

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together with potassium diselenide, and the other involving the
elimination reaction of a selenium atom from an intermediate
monoanion 2Ј with the simultaneous formation of cyclic
selenide 5. The former route is supported by the fact that 4 was
isolated as one of the products when the reaction was inter-
rupted before the KBH4 reduction of 2. The proof for the latter
is that, when 1,2-dibromoethane was used for the attempted
synthesis of 3b (R = -CH2CH2-), no 3b was obtained but
instead the production of 4 was observed with the deposition of
red selenium metal which resulted from the decomposition of
unstable ethylene selenide. A similar phenomenon has been
reported by Batchelor et al.11
An alternative synthesis of 3c was carried out by the reduc-
tion of 1,2-diselenacyclopentane 6 with potassium borohydride
followed by the condensation of the resulting potassium
diselenide with 1 in 27% yield (Scheme 2). Two related macro-
Fig. 1 The ORTEP plot (30% probability level) for macrocycle 3c.
1185 cmϪ1 for P᎐O, 1431–1433 cmϪ1 for P–Ph and at 570–580
᎐
cmϪ1 and 529–541 cmϪ1 for C–Se. The 1H NMR spectra exhibit
two doublets characteristic of two equivalent ArCH2 groups at
δ 3.50–5.50 ppm with ∆δ of about 1.0 ppm and the geminal
coupling constant of about 12 Hz. The eight-membered com-
pound 4 showed two AB quartets of two nonequivalent ArCH2
due to the restricted rotation of the three benzene rings on the
phosphorus atom. A 31P NMR signal appears between δ 34.7
and 37.4 ppm as a singlet for macrocycles 3, 9 and 10 except 3l
which has two singlets at 37.40 and 36.95 ppm due to the exist-
ence of a cis–trans equilibrium between the P᎐O and CH–OH
᎐
group. On the other hand, the 31P NMR signal of 4 appears up-
field at δ 27.54 ppm, which could be ascribed to the increase of
ring strain. The electron impact mass spectra of these macro-
cycles 3, 4, 9 and 10 exhibited a molecular ion isotopic cluster as
expected, among which the molecular ion peak calculated as
80Se was highest.
X-Ray crystallographic analysis of macrolides 3c, 3f and 10
The structures of 3c, 3f and 10 were finally established by X-ray
crystallographic analyses (Table 2). Fig. 1 shows the molecular
structure of 3c in which the phosphoryl P᎐O bond is directed
᎐
upwards to the inside of the macrocyclic ring. The unit cell
contains four sets of two independent molecules (I and II)
which cannot be transformed into one another by either a
symmetrical or translational operation. There are no significant
differences in the bonding parameters between I and II. The
selected bond lengths and bond angles are listed in Table 3 and
Table 4. The only difference between the two molecules is seen
in the dihedral angles between the benzene ring planes, which
are given in Table 5.
Scheme 2
The molecular structures of 3f and 10 are shown in Fig. 2
and Fig. 3, respectively. The geometrical arrangements of the
triphenylphosphine oxide group in 3f and 10 are similar to that
cycles 9 and 10 containing two ethereal oxygen atoms in the
cycle (Scheme 2) were also synthesized by the condensation of
1 with 3-selenapentane-1,5-diol 7 and 3,7-diselenanonane-1,9-
diol 8 in the presence of sodium tert-butoxide in yields of 26%
and 22%, respectively.
of 3c, so that the phosphoryl P᎐O bond is directed upwards
᎐
to the inside of the macrocyclic ring. Table 5 also shows the
dihedral angles between the three benzene ring planes in the
crystals of 3f and 10.
Spectral properties of the macrocycles
Complexation of the macrolides with palladium(II) chloride
All the macrolides 3a, 3c–3l, 4, 9 and 10 were characterized by
their elemental analyses and IR, 1H NMR, 31P NMR and mass
spectral measurements. IR absorption bands appear at 1170–
Two solvent systems were used for the preparation of palladium
chloride complexes of the macrolides. (1) Method A. Com-
plexes 11, 12, 13 and 21 were prepared in 26, 48, 86 and 99%
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146
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Table 2 X-Ray data collection parameters for compounds 3c, 3f, 10 and 21
Macrocycle
3c
3f
10a
21
Chemical formula
Formula Weight
C23H23OPSe2
504.30
C26H29OPSe2
546.38
C27H31O3PSe2
592.44
C22H30Cl2O10 P2PdSe2
819.26
Crystal system
Monoclinic
P21/n (No. 14)
3.600
Triclinic
P1(No. 2)
3.153
Orthorhombic
Pbca (No. 61)
2.9127
Triclinic
P1(No.2)
3.499
¯
¯
Space group
µ/mmϪ1
R
Rw
0.1628
0.1876
0.1133
0.1913
0.083
0.088
0.0838
0.1774
a/Å
b/Å
c/Å
α/deg
13.524(3)
22.784(5)
14.838(3)
90.00(0)
112.98(3)
90.00(0)
8.294(2)
8.305(2)
18.438(4)
100.38(3)
96.14(3)
102.78(3)
1204(1)
16.012(3)
17.047(3)
18.176(4)
90.00(0)
90.00(0)
90.00(0)
4961(1)
7.655(2)
15.047(3)
20.023(4)
72.73(3)
83.49(3)
80.64(3)
2168(1)
β/deg
γ/deg
V/Å3
4209(2)
T/K
Z
293(2)
8
293(2)
2
298(1)
8
293(2)
3
Measured/
independent reflections
5930/5680 [Rint = 0.0859]
4156/4015 [Rint = 0.0452]
4967/3516
6040/5836 [Rint = 0.0854]
a Refinement on F.
Table 3 The selected bond lengths of macrocycle 3c (Å)
Se(1)–C(1)
Se(1)–C(2)
Se(2)–C(4)
Se(2)–C(5)
P(1)–O(1)
P(1)–C(11)
P(1)–C(21)
P(1)–C(31)
2.002(16)
1.929(17)
1.930(19)
1.941(14)
1.478(8)
1.786(14)
1.830(11)
1.819(14)
Se(3)–C(6)
Se(3)–C(7)
Se(4)–C(9)
Se(4)–C(10)
P(2)–O(2)
P(2)–C(41)
P(2)–C(51)
P(2)–C(61)
1.983(15)
1.967(19)
1.941(24)
1.934(14)
1.452(9)
1.803(14)
1.795(12)
1.823(14)
Table 4 The selected bond angles of macrocycle 3c (Њ)
C(1)–Se(1)–C(2)
C(4)–Se(2)–C(5)
C(11)–P(1)–C(21)
C(11)–P(1)–C(31)
C(21)–P(1)–C(31)
101.0(7)
98.6(7)
103.7(6)
107.2(7)
108.9(5)
C(6)–Se(3)–C(7)
C(9)–Se(4)–C(10)
C(41)–P(2)–C(51)
C(41)–P(2)–C(61)
C(51)–P(2)–C(61)
100.2(7)
98.3(8)
103.6(6)
105.8(7)
107.2(5)
Table 5 The dihedral angles between the benzene ring planes in the
macrocycles 3c, 3f and 10 (Њ)
Molecule in
crystal state
1 and 2
1 and 3
2 and 3
Fig. 2 The ORTEP plot (30% probability level) for macrocycle 3f.
3c(I)
3c(II)
3f
81.8
91.9
79.0
96.8
92.4
85.0
91.6
106.6
107.6
92.3
10
107.1
84.5
yields, respectively, by heating a solution of palladium chloride
and 3c, 9, 10 and 20 in 50 : 2 acetone–water for 26 h. (2)
Method B. Complexes 14, 15, 16, 17, 18 and 19 were prepared
in 83–95% yields by heating a solution of palladium chloride
and 3d, 3e, 3f, 3g, 3j and 3l, respectively, in acetonitrile. Some
properties of these palladium complexes are shown in Table 6.
Except for 12 and 13, the palladium complexes were so
sparingly soluble in deuterated solvents that the NMR spectra
were not measured. The elemental analyses indicated that the
palladium complexes having two selenium atoms in the ring
were 1 : 1 complexes, while complex 12 having one selenium
atom was a 2 : 1 complex.
Although we were not successful in obtaining a single crystal
for X-ray crystallography from any of these palladium
complexes, we succeeded in obtaining a single crystal of the
2 : 1 palladium complex 21 of a related selenium-containing
phosphocane 20 which was previously synthesized in our
laboratory.10,12 Fig. 4 shows (a) the molecular structure and
(b) the crystal packing of complex 21. In the unit cell, three
Fig. 3 The ORTEP plot (30% probability level) for macrocycle 10.
tetracoordinate palladium complexes are arranged in a centro-
symmetric manner to form square planar structures. The
central palladium atom is coordinated by two Pd–Se bonds and
two Pd–Cl bonds with equal bond lengths of 2.442 and 2.289
1142
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146

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Table 6 Some properties of Pd()Cl2 complexes
Parent macrocycle
Pd() complex
λmax/nm (solvent)
εmax/dm3 molϪ1cmϪ1
Ligand : Pd ratio
3c
9
11
12
13
325 (DMSO)
300 (CHCl3)
301 (CHCl3)
405 (CHCl3)
nda
325 (CHCl3)
325 (DMSO)
327 (DMSO)
nda
450
11400
88600
16300
nda
2470
2820
4720
nda
1 : 1
2 : 1
1 : 1
10
3d
3e
3f
14
15
16
17
18
19
21
1 : 1
1 : 1
1 : 1
1 : 1
1 : 1
1 : 1
2 : 1
3g
3k
3l
327 (DMSO)
325 (CHCl3)
5300
10100
20
a nd: because of its low solubility, the UV spectrum of this compound was not determined.
Scheme 3
The same types of down-field shifts were observed in the
cases of the 1 : 1 palladium complex 13. Thus, the signals of the
proton α to the selenium atom in 10 (δ 2.45–2.27 ppm) are
shifted 0.1–1.0 ppm to lower field (δ 3.49–2.37 ppm) for 13
suggesting the coordination of selenium atoms to palladium.
On the other hand, the proton signals of Ar–CH2–O– at 4.50
and 5.30 ppm and of –O–CH2– at 3.68–3.61 ppm for 10 were
shifted 0–0.2 ppm and 0.2–0.6 ppm, respectively, to lower field
(δ 4.47–5.49 ppm and 3.75–4.25 ppm, respectively) for 13. The
down-field shift occurring with the –O–CH2– protons suggested
that the partial coordination of palladium chloride to the
ethereal oxygen atoms of 10 might occur. Further proof was
obtained from the UV spectrum of 13 with λmax/nm at 405
(ε/dm3 molϪ1 cmϪ1 16300) and 301 (ε 88600), of which the
former was absent in complex 12. All other 1 : 1 palladium
complexes 11, 15, 16, 17 and 19 exhibit λmax near 325 nm with
Fig. 4 (a) The ORTEP plot (30% probability level) for Pd complex 21
(b) The crystal packing of Pd complex 21.
relatively low ε
similar type of structure.
(Table 6), suggesting that they may have a
Å, respectively, and the Cl–Pd–Cl and Se–Pd–Se angles are
both 180Њ. On the other hand, the outer two palladium atoms
are coordinated by two Pd–Se bonds and two Pd–Cl bonds with
different bond lengths of 2.434 and 2.429 Å (Pd–Se) and 2.291
and 2.284 Å (Pd–Cl), respectively, and the Cl–Pd–Cl and
Se–Pd–Se angles are 179.5Њ and 174.9Њ, respectively.
max
Experimental
All synthetic manipulations were carried out under a nitrogen
atmosphere using the conventional Schlenk technique. Tetra-
hydrofuran (THF) was distilled from sodium–benzophenone
immediately prior to use. Column chromatography and pre-
parative TLC were carried out on silica gel (Qing Dao 300 and
GF254, respectively). Melting points were measured with open
capillaries and are uncorrected. IR spectra were recorded on a
Bio-Rad FTS 3000 spectrometer. 1H and 31P NMR spectra were
recorded on a Bruker AC-P 200 spectrometer using SiMe4 as
internal standard and 85% phosphoric acid as external stand-
ard, respectively. Mass spectra were recorded at an ionizing
voltage of 70 eV. Elemental analyses were performed on a
Yanaco CHN CORDER MT-3 analyzer.
We looked at the expected down-field shift of the resonance
of the protons α to the selenium atom occurring on the trans-
formation of macrolides 20 and 9 into the 2 : 1 palladium com-
plexes 21 and 12 (Scheme 3). The signals (δ 2.86 and 3.12 ppm)
of the protons α to the selenium atom for 20 are shifted 0.5–0.6
ppm to lower field (δ 3.50 and 3.60 ppm) for 21, while those
(δ 2.15 and 2.79 ppm) for 9 are shifted 0.6–0.7 ppm to lower
field (δ 2.89 and 3.46 ppm) for 12. This down-field shift resulted
from the decrease of electron density on the selenium atom
after complexation. It should be noted that only small down-
field shifts (0–0.2 ppm) were observed for the protons α to the
oxygen atoms of 12 and 21, indicating that no coordination of
palladium() occurs on the oxygen atoms. Furthermore, com-
plexes 12 and 21 had similar UV absorptions with λmax/nm at
300 (ε/dm3 molϪ1 cmϪ1 11400) and 325 (ε 10100), respectively.
All the above facts indicate that the 2 : 1 palladium complex 12
has the same type of structure as 21.
Bis[o-(bromomethyl)phenyl]phenylphosphine oxide 1,13 1,2-
diselenacyclopentane 6,14 3-selenapentane-1,5-diol 7,12 3,7-
diselenanonane-1,9-diol 815 and 2-(p-methylphenoxy)-2-
oxo-1,3,6,2λ5-dioxaselenaphosphocane 2010,12 were prepared
according to the literature methods.
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146
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General procedure for preparing macrocycles 3
yield; mp 135–136 ЊC; δH(CDCl3) 7.75–6.77(13H, m), 4.75(2H,
d, J 11.8), 3.78(2H, d, J 11.8), 2.78–2.48(4H, m), 1.88–1.29(8H,
m); δP(CDCl3) 36.02; m/z(EI) 548 (M+, 2%), 385 (22), 304 (100),
178 (76), 165 (80); νmax(KBr)/cmϪ1 3050(ArH), 2905(ws, CH2),
A 250 mL three-necked flask was charged with selenium
powder (0.49 g, 6.2 mmol), potassium borohydride (0.24 g, 4.4
mmol) and absolute ethanol (50 mL). Nitrogen gas was intro-
duced with a glass inlet tube to the bottom of the flask. The
mixture was stirred under reflux for 2 h. Then compound 1
(0.93 g, 2 mmol) dissolved in THF (60 mL) was added during a
period of 1.5 h. After the mixture was stirred under reflux for
another 4 h, sodium hydroxide (0.24 g, 6.0 mmol) and potas-
sium borohydride (0.32 g, 6.0 mmol) were added. When the
mixture turned clear and colourless, a solution of an appropri-
ate dihaloalkane (2 mmol) in THF (60 mL) was added dropwise
over 3 h. After the mixture was refluxed for another 12 h, the
reaction mixture was cooled and solid materials removed by
filtration and the evaporation of the filtrate gave a white solid,
which was mixed with chloroform (50 mL) and water (50 mL)
under shaking. The organic phase was separated and washed to
neutral with water (2 × 20 mL), dried with anhydrous mag-
nesium sulfate and evaporated. The residue was purified by
preparative TLC to give macrocycles 3a, 3c–3l and the eight-
membered heterocycle 4. The yields of 3 and 4 are given in
Table 1.
1433(P–Ph), 1170(P᎐O), 570, 530(C–Se); Anal. C H OPSe
᎐
26 29
2
(MW 546.38): Calcd. C, 57.15; H, 5.35. Found, C, 57.23; H,
5.45%.
5-Phenyl-5,12,13,15,16,18-hexahydro-10H-5ꢀ5-dibenzo[ f,i]-
[1,4,12,8]oxadiselenaphosphacyclotetradecin-5-one 3g. Colour-
less crystals (from dichloromethane and petroleum ether), 30%
yield; mp 176–180 ЊC; δH(CDCl3) 7.74–6.82(13H, m), 4.93(2H,
d, J 12.4), 3.81(2H, d, J 12.4), 3.89–3.78(2H, m), 3.39–3.26(2H,
m), 3.20–3.06(2H, m), 2.60–2.46(2H, m); δP(CDCl3) 36.43;
m/z(EI) 536 (M+, 1%), 385 (14), 303 (100), 179 (73), 165 (77),
91 (36); νmax(KBr)/cmϪ1 3050(ArH), 2920, 2840, 2820(CH2),
1433(P–Ph), 1179(P᎐O), 570, 538(C–Se); Anal. C H O PSe
᎐
24 25
2
2
(MW 534.33): Calcd. C, 53.94; H, 4.72. Found, C, 54.06; H,
5.06%.
5-Phenyl-5,12,13,15,16,18,19,21-octahydro-10H-5ꢀ5-dibenzo-
[i,l][1,4,7,15,11]dioxadiselenaphosphacycloheptadecin-5-one 3h.
Colourless crystals (from dichloromethane and petroleum
ether), 21% yield; mp 119–120 ЊC; δH(CDCl3) 7.74–6.89(13H,
m), 4.60(2H, d, J 12.6), 3.97(2H, d, J 12.6), 3.75–3.55(8H, m),
2.80(4H, m); δP(CDCl3) 35.57; m/z(EI) 580 (M+, 2%), 383 (28),
303 (100), 178 (62), 165 (66); νmax(KBr)/cmϪ1 3053(ArH),
5-Phenyl-5,14-dihydro-10H-5ꢀ5-dibenzo[e,h][1,3,7]diselena-
phosphecin-5-one 3a. Colourless crystals (from dichloro-
methane and petroleum ether), 24% yield; mp 176–178 ЊC;
δH(CDCl3) 7.53–7.20(13H, m), 5.31(2H, d, J 12.2), 4.50(1H, d,
J 11.5), 4.03(1H, d, J 11.5), 3.94(2H, d, J 12.2); δP(CDCl3)
34.70; m/z(EI) 478 (M+, 2%), 384 (17), 303 (60), 213 (16), 179
(96), 165 (100), 91 (46); νmax(KBr)/cmϪ1 3060(ArH), 2940
2926, 2854(CH ), 1439(P–Ph), 1178(P᎐O), 1114(C–O), 578,
᎐
2
547(C–Se); Anal. C26H29O3PSe2 (MW 578.38): Calcd. C, 53.79;
H, 5.05. Found, C, 54.04; H, 4.96%.
(CH ), 1433(P–Ph), 1179(P᎐O), 571, 539(C–Se); Anal. C H -
OPSe2 (MW 476.25): Calcd. C, 52.96; H, 4.02. Found, C, 53.03;
H, 4.06%.
12-Phenyl-5,12,17,19-tetrahydro-7H-12ꢀ5-tribenzo[c,h,k]-
[1,9,5]diselenaphosphacyclotridecin-12-one 3i. White powder,
25.6% yield; mp 186–187 ЊC; δH(CDCl3) 7.50–6.90(17H, m),
4.97(2H, d, J 11.4), 4.23(2H, d, J 11.9), 4.05(2H, d, J 11.4),
3.84(2H, d, J 11.9); δP(CDCl3) 35.27; m/z(EI) 568 (M+, 3%), 487
(3), 385 (21), 303 (48), 178 (62), 104 (100); ν max(KBr)/cmϪ1
᎐
2
21 19
5-Phenyl-5,13,14,16-tetrahydro-10H,12H-5ꢀ5-dibenzo[g, j ]-
[1,5,9]diselenaphosphacyclododecin-5-one 3c. Colourless crys-
tals (from dichloromethane and petroleum ether), 22% yield;
mp 206–208 ЊC; δH(CDCl3) 7.80–6.80(13H, m), 5.50(2H, d,
J 10.8), 3.90(2H, d, J 10.8), 2.92–1.80(6H,m); δP(CDCl3) 36.53;
m/z(EI) 506 (M+, 2%), 304 (100), 202 (5); νmax(KBr)/cmϪ1
3050(ArH), 2920(CH ), 1433(P–Ph), 1181(P᎐O), 571, 545,
᎐
2
535(C–Se); Anal. C28H25OPSe2 (MW 566.37): Calcd. C, 59.37;
H, 4.45. Found, C, 59.44; H, 4.40%.
11-Phenyl-11,16-dihydro-4H,6H,18H-11ꢀ5-tribenzo[c,f,kl]-
[1,9,5]diselenaphosphacyclotetradecin-11-one 3j. White powder,
16% yield; mp 169–170 ЊC; δH(CDCl3) 7.76–6.66(17H, m),
4.75(2H, d, J 13.5), 3.87(2H, d, J 12.9), 3.71(2H, d, J 13.5),
3.63(2H, d, J 12.9); δP(CDCl3) 36.32; m/z(EI) 568 (M+, 1%), 385
(12), 303 (60), 179 (100), 104 (45); νmax(KBr)/cmϪ1 3050(ArH),
3050(ArH), 2920(CH2), 1433(P–Ph), 1181(P᎐O), 571,
533(C–Se); Anal. C23H23OPSe2 (504.31): Calcd. C, 54.77; H,
4.60. Found, C, 54.50; H, 4.63%.
᎐
5-Phenyl-5,12,13,14,15,17-hexahydro-10H-5ꢀ5-dibenzo[c, f ]-
[1,9,5]diselenaphosphacyclotridecin-5-one 3d. Colourless crys-
tals (from dichloromethane and petroleum ether), 25% yield;
mp 171–173 ЊC; δH(CDCl3) 7.57–6.75(13H, m), 5.12(2H, d,
J 11.2), 3.69(2H, d, J 11.2), 3.23–3.12(2H, m), 2.49–2.36(2H,
m), 1.58(4H, m); δP(CDCl3) 37.36; m/z(EI) 520 (M+, 1%), 385
(8), 304 (100), 178 (54), 165 (55); νmax(KBr)/cmϪ1 3050(ArH),
2930(CH ), 1439, 1431(P–Ph), 1170(P᎐O), 575, 536(C–Se);
᎐
2
Anal. C28H25OPSe2 (MW 566.37): Calcd. C, 59.37; H, 4.45.
Found, C, 59.74; H, 4.31%.
10-Phenyl-3,10,15,17-tetrahydro-5H-tribenzo[c,f,klm][1,9,5]-
diselenaphosphacyclopentadecin-10-one 3k. White powder, 35%
yield; mp 209–212 ЊC; δH(CDCl3) 7.85–6.56(17H, m), 4.44(2H,
d, J 13.7), 3.81(4H, ABq, J 11.5), 3.53(2H, d, J 13.7); δP(CDCl3)
35.66; m/z(EI) 568 (M+, 2%), 464 (1), 383 (11), 304 (67),
179 (50), 165 (47), 104 (100); νmax(KBr)/cmϪ1 3040(ArH),
2920(CH ), 1433(P–Ph), 1179(P᎐O), 570, 532(C–Se); Anal.
᎐
2
C24H25OPSe2 (MW 518.33): Calcd. C, 55.61; H, 4.86. Found, C,
55.80; H, 4.94%.
5-Phenyl-5,13,14,15,16,18-hexahydro-10H,12H-5ꢀ5-dibenzo-
[c, f ][1,9,5]diselenaphosphacyclotetradecin-5-one 3e. Colourless
crystals (from dichloromethane and petroleum ether), 12%
yield; mp 147–148 ЊC; δH(CDCl3) 7.66–6.79(13H, m), 4.84(2H,
d, J 12.6), 3.77(2H, d, J 12.6), 2.88–2.74(2H, m), 2.47–2.33(2H,
m), 1.87–1.76(4H, m), 1.54–1.18(2H, m); δP(CDCl3) 36.45;
m/z(EI) 534 (M+, 1%), 385 (10), 304 (100), 178 (55), 165
(60); νmax(KBr)/cmϪ1 3060(ArH), 2908(CH2), 1433(P–Ph),
2910(CH ), 1433(P–Ph), 1174(P᎐O), 570, 529(C–Se); Anal.
᎐
2
C28H25OPSe2 (MW 566.37): Calcd. C, 59.37; H, 4.45. Found, C,
59.71; H, 4.61%.
5-Phenyl-13-hydroxy-5,13,14,16-tetrahydro-10H,12H-5ꢀ5-
dibenzo[g,j ][1,5,9]diselenaphosphacyclododecin-5-one 3l.
Colourless crystals (from dichloromethane and petroleum
ether), 15% yield; mp 210–2 ЊC; δH(CDCl3) 7.60–6.91(13H, m),
5.35(2H, d, J 10.5), 4.33(1H, br s, OH), 3.80(2H, d, J 10.5),
1180(P᎐O), 570, 537(C–Se); Anal. C H OPSe (532.36):
᎐
25 27
2
Calcd. C, 56.40; H, 5.11. Found, C, 56.41; H, 5.14%.
3
2
3.67(1H, br s, CH), 3.12(2H, dd, J 4.2, J 13.8), 2.72(2H, dd,
3J 6.9, 2J 13.8); δP(CDCl3) 37.40, 36.95; m/z(EI) 522 (M+, 0.3%),
464 (0.6), 384 (10), 303 (40), 213 (15), 179 (84), 165 (58), 58
(100); νmax(KBr)/cmϪ1 3350(ws, O–H), 3050(ArH), 2910(CH2),
5-Phenyl-5,12,13,14,15,16,17,19-octahydro-10H-5ꢀ5-dibenzo-
[c, f ][1,9,5]diselenaphosphacyclopentadecin-5-one 3f. Colourless
crystals (from dichloromethane and petroleum ether), 19%
1144
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146

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1433(P–Ph), 1170(P᎐O), 575, 535(C–Se); Anal. C H O PSe
2
(MW 520.30): Calcd. C, 53.09; H, 4.45. Found, C, 53.14; H,
4.40%.
3.61(4H, m), 2.45–2.27(8H, m), 2.01–1.79(2H, m); δPNMR-
᎐
23 23
2
(CDCl3) 35.13; m/z(EI) 594 (M+, 6%), 335 (62), 319 (100),
289 (43), 134 (14), 107 (11); νmax(KBr)/cmϪ1 1441(P–Ph),
1189(P᎐O), 545(C–Se). Anal. C H O PSe : Calcd. C, 54.74;
H, 5.28. Found, C, 54.48; H, 5.24%.
᎐
27 31
3
2
12-Phenyl-7,12-dihydro-5H-12ꢀ5-dibenzo[c, f ][1,5]selena-
phosphocin-12-one 4. White powder, mp 195–6 ЊC; δH(CDCl3)
8.12–7.02(13H, m), 3.98(2H, ABq, J 13.6), 3.63(2H, ABq,
J 12.5); m/z(EI) 384 (M+, 18%), 303 (33), 213 (11), 179 (100),
165 (65), 137 (13); δP(CDCl3) 27.54; νmax(KBr)/cmϪ1 1433(P–
Synthesis of palladium(II) complexes
Method A:. A solution of the macrocycle 3c (0.10 mmol), 9
(0.20 mmol), 10 (0.20 mmol) or 2010,12 (0.20 mmol) and pal-
ladium chloride (0.10 mmol) in acetone (50 mL) and water
(2 mL) was stirred under reflux for 36 h. The solvent was
removed and a yellow powder was obtained which was washed
thoroughly with acetone to give complexes 11, 12, 13 or 21
respectively.
Ph), 1185(P᎐O), 580, 541, 517(C–Se); Anal. C H OPSe (MW
᎐
20 17
383.27): Calcd. C, 62.67; H, 4.47; Found, C, 62.97; H, 4.50%.
Alternative synthesis of 5-phenyl-5,13,14,16-tetrahydro-10H,
12H-5ꢀ5-dibenzo[g,j ][1,5,9]diselenaphosphacyclododecin-5-one
3c
Dichloro(5-phenyl-5,13,14,16-tetrahydro-10H,12H-5λ5-
dibenzo[g,j][1,5,9]diselenaphosphacyclododecin-5-one-κ2Se,
SeЈ)palladium 11. Yellow powder, 26% yield; mp 240 ЊC dec.;
νmax(KBr)/cmϪ1 3150, 1433, 1181, 1174, 571, 535; λmax(DMSO)/
nm 325 (ε/dm3 molϪ1 cmϪ1 450); Anal. C23H23OPSe2ؒPdCl2:
Calcd. C, 40.53; H, 3.40. Found, C, 40.86; H, 3.60%.
A stirred mixture of 1,2-diselenacyclopentane 6 (1.0 g, 5 mmol),
sodium hydroxide (0.6 g, 15 mmol), potassium borohydride
(0.81 g, 15 mmol) and absolute ethanol (100 mL) was heated
under reflux until the solution became clear and colourless. To
this solution was slowly added over 8.5 h a solution of
bis[o-(bromomethyl)phenyl]phenylphosphine oxide 1 (2.32 g,
5 mmol) in absolute ethanol (50 mL). The mixture was refluxed
for another 12 h. The solid deposited was removed by filtration.
After removal of the solvent, the residue was distributed
between methylene chloride (100 mL) and water (100 mL). The
aqueous layer was extracted with methylene chloride (2 × 50
mL). The organic phases were combined, washed with brine,
dried over MgSO4, and evaporated in vacuo. The crude product
was purified by chromatography on silica gel eluting with
CH2Cl2 and recrystallized from absolute ethanol to give 0.67 g
(27%) of pure 3c as pale yellow crystals.
Dichlorobis(5-phenyl-5,12,13,15,16,18-hexahydro-10H-5λ5-
dibenzo[i,l][1,7,4,11]dioxaselenaphosphacyclotetradecin-5-one)-
palladium 12. Yellow powder, 48% yield; mp 238 ЊC dec.;
δH(CDCl3) 7.69–6.92(13H, m), 5.17(2H, br s), 4.58(2H, d,
J11.1), 4.13–3.75(4H, br d), 3.55–3.37(2H, br d), 3.13–2.64(2H,
br d); νmax(KBr)/cmϪ1 1435, 1191, 545; λmax(CHCl3)/nm 300
(ε/dm3 molϪ1 cmϪ1 11400); Anal. (C24H25O3PSe)2ؒPdCl2 Calcd.
C, 51.47; H, 4.50. Found, C, 51.41; H, 4.55%.
Dichloro(5-phenyl-5,12,13,16,17,19,20,22,-octahydro-10H,
15H-5λ5-dibenzo[m,p][1,11,4,8,15]dioxadiselenaphosphacyclo-
octadecin-5-one-κ2Se,SeЈ)palladium 13. Yellow powder, 89%
yield; mp 259 ЊC dec.; δH(CDCl3) 7.90–6.67(m, 13H), 5.49(1H,
d, J 11.4), 5.28(1H, d, J 11.5), 4.56(1H, d, J 11.5), 4.47(1H, d,
J 11.5), 4.25–4.10(1H, m), 4.05–3.86(1H, m), 3.82–3.75(2H, m),
3.49–3.24(1H, m), 3.17–2.95(1H, m), 2.85–2.37(6H, m), 2.25–
1.66(2H, m); νmax(KBr)/cmϪ1 3058, 2923, 1439, 1183, 1092 and
547; λmax(CHCl3)/nm 301 (ε/dm3 molϪ1 cmϪ1 88600) and 405
(16300); Anal. C27H31O3PSe2ؒPdCl2 Calcd. C, 42.13; H, 4.05.
Found, C, 41.99; H, 4.32%.
Synthesis of 5-phenyl-5,12,13,15,16,18-hexahydro-10H-5ꢀ5-
dibenzo[i,l][1,7,4,11]dioxaselenaphosphacyclotetradecin-5-one 9
To a 250 mL three-necked flask was added sodium (0.10 g, 4.34
mmol) and tBuOH (20 mL). The mixture was refluxed until the
sodium disappeared. To the mixture was added a solution of
3-selenapentane-1,5-diol 7 (0.34 g, 2 mmol) in THF (50 mL).
After the addition was completed, the reaction mixture was
refluxed for 1 h. Then a solution of bis[o-(bromomethyl)-
phenyl]phenylphosphine oxide 1 in THF (50 mL) was added
slowly over 8 h. The reaction mixture was refluxed for another
24 h. The solid deposited was filtered off and the solvent was
evaporated from the filtrate to leave a solid material which
was dissolved in chloroform (50 mL). The chloroform solution
was washed to neutral with water, dried over MgSO4 and evap-
orated in vacuo. The crude product was purified by chrom-
atography on silica gel eluting with CH2Cl2–Et2O 10 : 1 and
recrystallized from Et2O to give 0.25 g (26%) of pure 9 as
colourless crystals, mp 115–116 ЊC; δH(CDCl3) 7.59–6.69(13H,
m), 5.42(2H, d, J 11.5), 4.39(2H, d, J 11.5), 4.12–3.97(2H, m),
3.80–3.63(2H, m), 2.90–2.68(2H, m), 2.24–2.05(2H, m);
δP(CDCl3) 34.98; m/z(EI) 472 (M+, 12%), 365 (21), 335 (79), 319
(95), 165 (100), 134 (45), 107 (29). νmax(KBr)/cmϪ1 1438(P–Ph),
Dichlorobis[2-(p-methylphenoxy)-2-oxo-1,3,6,2-dioxaselena-
phosphocane]palladium 21. Reddish brown crystals, 99% yield;
mp 192–4 ЊC; δH (CDCl3) 7.10(s, 4H, ArH), 4.72(br t, 2H,
OCH2), 4.42(br m, 2H, OCH2), 3.60(br s, 2H, SeCH2), 3.50(br s,
2H, SeCH2), 2.30(s, 3H, ArCH3); m/z(EI). 322 (20+, 4%), 215
(12), 134 (100); νmax(KBr)/cmϪ1 1276(s, P᎐O), λmax(CHCl3)/nm
᎐
325 (ε/dm3 molϪ1 cmϪ1 10100); Anal. C22H30Cl2O10P2PdSe2
(819.63). Calcd.: C, 32.24; H, 3.69. Found, C, 31.86; H, 3.86%.
Method B:. 50 mg of macrocycles 3d, 3e, 3f, 3g, 3k or 3l and
an equimolar amount of palladium chloride in deoxygenated
acetonitrile (20 mL) were stirred under reflux for 2 h to give a
yellow powder, which was collected by filtration and washed
sufficiently with ether to give complexes 14, 15, 16, 17, 18 or 19
respectively.
Dichloro(5-phenyl-5,12,13,14,15,17-hexahydro-10H-5λ5-
dibenzo[c,f][1,9,5]diselenaphosphacyclotridecin-5-one-κ2Se,
SeЈ)palladium 14. Yellow powder, 85% yield; mp >230 ЊC dec.;
νmax(KBr)/cmϪ1 1432, 1181, 1179, 1119, 1111, 540; Anal.
C24H25OPSe2ؒPdCl2 (MW 695.64) Calcd. C, 41.13; H, 3.62.
Found, C, 41.50; H, 3.86%.
1188(P᎐O), 545(C–Se). Anal. C H O PSe: Calcd. C, 61.15; H,
᎐
24 25
3
5.35. Found, C, 60.95; H, 5.48%.
Synthesis of 5-phenyl-5,12,13,16,17,19,20,22,-octahydro-10H,
15H-5ꢀ5-dibenzo[m,p][1,11,4,8,15]dioxadiselenaphosphacyclo-
octadecin-5-one 10
Dichloro(5-phenyl-5,13,14,15,16,18-hexahydro-10H,12H-5λ5-
dibenzo[c,f][1,9,5]diselenaphosphacyclotetradecin-5-one-κ2Se,
SeЈ)palladium 15. Yellow powder, 90% yield; mp 219–220 ЊC
dec.; νmax(KBr)/ 1433, 1178, 1115, 535 cmϪ1; λmax(DMSO)/nm
325 (ε/dm3 molϪ1 cmϪ1 2470); Anal. C25H27OPSe2ؒPdCl2 (MW
709.674) Calcd. C, 42.31; H, 3.84. Found, C, 41.92; H, 3.67%.
Dichloro(5-phenyl-5,12,13,14,15,16,17,19-octahydro-10H-
5λ5-dibenzo[c,f][1,9,5]diselenaphosphacyclopentadecin-5-one-
κ2Se,SeЈ)palladium 16. Yellow powder, 83% yield; mp >230 ЊC
Following the method for preparing macrocycle 9, macrocycle
10 was synthesized from 3,7-diselenanonane-1,9-diol 8 (0.58 g,
2 mmol), bis[o-(bromomethyl)phenyl]phenylphosphine oxide 1
(0.93 g, 2 mmol). The crude product was purified by chrom-
atography over silica gel eluting with CH2Cl2–Et2O 10 : 1 and
recrystallized from Et2O to give 0.26 g (22%) of pure 10 as
colourless prismatic crystals, mp 131–132 ЊC; δH(CDCl3) 7.71–
6.96(13H, m), 5.30(2H, d, J 12.8), 4.50(2H, d, J 12.8), 3.68–
J. Chem. Soc., Perkin Trans. 1, 2001, 1140–1146
1145

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dec.; νmax(KBr)/cmϪ1 1433, 1185, 1181, 1175, 1119, 1111, 540;
λmax(DMSO)/nm 325 (ε/dm3 molϪ1 cmϪ1 2820); Anal. C26H29-
OPSe2ؒPdCl2 (MW 723.69) Calcd. C, 43.14; H, 3.52. Found, C,
43.05; H, 3.80%.
structures were solved by direct method and developed by using
full-matrix least-squares refinement. The raw data were cor-
rected for absorption using DIFABS. All non-H atoms were
refined anisotropically, while H atoms were added theoretically
and refined with riding model position parameters and fixed
isotropic thermal parameters. A summary of the crystallo-
graphic data and data collection and refinement parameters are
given in Table 2.
Dichloro(5-phenyl-5,12,13,15,16,18-hexahydro-10H-5λ5-
dibenzo[f,i][1,4,12,8]oxadiselenaphosphacyclotetradecin-5-one-
κ2Se,SeЈ)palladium 17. Yellow powder, 85% yield; mp >221 ЊC
dec.; νmax(KBr)/cmϪ1 1435, 1180, 1175, 1119, 1111, 539;
λmax(DMSO)/nm 327 (ε/dm3 molϪ1 cmϪ1 4720); Anal. C24H25-
O2PSe2ؒPdCl2 (MW 711.64) Calcd. C, 40.50; H, 3.54. Found, C,
40.47; H, 3.52%.
Acknowledgements
Dichloro(10-phenyl-3,10,15,17-tetrahydro-5H-tribenzo-
[c,f,klm][1,9,5]diselenaphosphacyclopentadecin-10-one-κ2Se,
SeЈ)palladium 18. Yellow powder, 95% yield; mp 239.5 ЊC dec.; -
νmax(KBr)/cmϪ1 1433, 1191, 1179, 1118, 539; Anal. C24H25O2-
PSe2ؒPdCl2 (MW 743.68) Calcd. C, 45.22; H, 3.39. Found, C,
45.00; H, 3.39%.
Dichloro(5-phenyl-13-hydroxy-5,13,14,16-tetrahydro-10H,
12H-5λ5-dibenzo[g,i][1,5,9]diselenaphosphacyclododecin-5-
one-κ2Se,SeЈ)palladium 19. Yellow powder, 83% yield; mp
>208 ЊC dec.; νmax(KBr)/cmϪ1 1435, 1180, 1175, 1115, 539;
λmax(DMSO)/nm 327 (ε/dm3 molϪ1 cmϪ1 5300); Anal. C23H23-
O2PSe2ؒPdCl2 (MW 697.61) Calcd. C, 39.60; H, 3.32. Found, C,
39.92; H, 3.43%.
Financial support from the National Natural Science
Foundation of China is gratefully acknowledged.
References
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