Designed synthesis of metal-organic frameworks containing gold(I) cations supported in phosphazene-phosphine polymeric matrices

Article abstract of DOI:10.1016/j.jorganchem.2008.10.034

The reaction of the polyphosphazenes {[NP(O₂C₁₂H₈)]_1-x [NP(OC₆H₄PPh₂)₂]_x }_n, x = 0.15 (1a), 0.25 (1b), 0.35 (1c), with [Au(THT)Cl] (THT = tetrahy

Full text of DOI:10.1016/j.jorganchem.2008.10.034

Journal of Organometallic Chemistry 694 (2009) 249–252
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Designed synthesis of metal-organic frameworks containing gold(I) cations
supported in phosphazene-phosphine polymeric matrices
*
Gabino A. Carriedo , Alejandro Presa, M.L. Valenzuela, Marc Ventalon
Departamento de Química, Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, C/Julián Clavería S/N, Oviedo 33071, Spain
a r t i c l e i n f o
a b s t r a c t
Article history:
8 1ꢀx 6 4 2 2 x n
The reaction of the polyphosphazenes {[NP(O2C12H )] [NP(OC H PPh ) ] } , x = 0.15 (1a), 0.25 (1b),
Received 9 September 2008
Received in revised form 16 October 2008
Accepted 16 October 2008
Available online 25 October 2008
0
.35 (1c), with [Au(THT)Cl] (THT = tetrahydrothiophene) in dichloromethane gave the polymers
[NP(O )]1ꢀx[NP(OC PPh AuCl) , x = 0.15, (2a), 0.25 (2b), 0.35 (2c), respectively. The reaction
of (1a) with [Au(PPh ]PF in refluxing THF led to the replacement of the PPh ligands giving a metal-
organic framework of idealized formula {[NP(O )]1ꢀx[NP(OC PPh (AuPF , x = 0.15, (3a),
–] cross-linking sites. The insoluble polymeric matrix
groups, was reacted with [Au(THT)Cl] to give the new polymeric framework
)]0.85[NP(OC PPh (AuPF 0.5(AuCl)0.5 (4).
Ó 2008 Elsevier B.V. All rights reserved.
{
2
C
12
H
8
6
H
4
2
2 x n
] }
3
)
2
6
3
2
C
12
H
8
H
6 4
2
)
2
6 0.5 x n
) ] }
+
2 2
0.25 (3b) containing cationic [–Ph P–Au –PPh
Keywords:
Polymers
Polyphosphazenes
Supported phosphines
Gold(I)
(3a), having pendant PPh
2
of composition {[NP(O
2
C
12
H
8
6
H
4
2
)
2
6
)
0.15 n
] }
1
. Introduction
The polymers having pendant MLn transition metal complexes
uble polymeric complexes with Au(I) having well defined compo-
sitions and regular structures. Herein we wish to report the
+
preparation of two polymeric matrices containing –PPh
2
–Au –
coordinated to a ligand that is attached to a polymeric chain by
an appropriate spacer [1] may be useful to design new catalysts
PPh
PPh
2
– cationic sites and neutral AuCl groups together with free
ligands available for further coordination, that can be in-
2
[
2]. In this respect, polyphosphazenes [3], that are convenient
cluded in the coordination polymers category of the general hybrid
inorganic–organic framework materials [8].
and versatile materials to support catalysts, have not been suffi-
ciently explored [2a,4]. In earlier studies, we have reported simple
synthetic methods to obtain a variety of polyphosphazene random
copolymers containing functional repeating units of the types
2
. Experimental
[
2 n
N@P(OR-L-MLn) ] carrying transition metal complexes [5a]. In
2.1. Materials and general techniques
general, the polymeric phosphazene complexes may be prepared
by two different routes: (a) the macromolecular-substitution of a
labile ligand (S) from a precursor complex MLn(S) using a polymer
carrying the coordinating group L; (b) the macromolecular-substi-
tution of Cl from a chlorine containing polyphosphazene with phe-
nolic complexes HO-R-L-MLn in the presence of caesium carbonate
All the reactions were carried out under dry nitrogen. The THF
was treated with KOH and distilled twice from Na in the presence
of benzophenone. Petroleum ether refers to that fraction with boil-
ing point in the range 60–65 °C. KPF (Aldrich) was used as pur-
6
chased. The complex [Au(THT)Cl] (THT = tetrahydrothiophene)
[
5b]. A variation of the first method may include also not labile li-
was prepared as described in the literature [9]. The well known
gands taking advantage of the macroligand effect of the polymers
[
10] [Au(PPh
using KPF instead of TlPF
phine HO-C -PPh was synthesized as described elsewhere
5b]. The phosphine containing polyphosphazenes {[NP(O
NP(OC PPh , x = 0.15 (1a), 0.25 (1b), 0.35 (1c) were
3
2
) ][PF
6
] complex was prepared by a modified method
to form insoluble cross-linked materials. Examples are the
6
6
as described below. The phenol-phos-
6
Ru(II)(g
-p-cymene) complexes supported on poly(spirophospha-
H
6 4
2
zene-pyridine) copolymers [6].
[
[
2 12 8
C H )]1ꢀx-
Although several Au(I) complexes have been considered as use-
ful catalysts for a variety of organic reactions [7], the incorporation
of Au(I) derivatives to polyphosphazenes, that begun very early
6
H
4
2 2 x n
) ] }
prepared by the same procedures previously described for the
analogous with x = 0.15 [11], 0.35 [5b] and 0.4 [12]. Significant data
[
4b], remains insufficiently explored. Therefore, we considered of
31
are: P NMR (CDCl
3
, ppm): ꢀ6.6 [NP(O
), with the expected intensity ratios. The spectra also
showed very weak bands at 28.7 (Ph P@O sites) indicating that
the fraction of oxidized PPh groups (less than 4%) can be ne-
glected. The H NMR showed broad signals at 7.1 and 6.7 for the
2
C
12
H
8
)], ꢀ22.3 [NP(OC
6 4 2
H -) ],
interest the design of new synthetic methods for soluble or insol-
ꢀ
6.2 (PPh
2
2
2
*
Corresponding author.
1
E-mail address: gac@uniovi.es (G.A. Carriedo).
0
022-328X/$ - see front matter Ó 2008 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2008.10.034

2
50
G.A. Carriedo et al. / Journal of Organometallic Chemistry 694 (2009) 249–252
aromatic rings and the practically absence of trapped solvents
maximum less that 2% in weight). Therefore the functionalization
degrees (FD in mmol of PPh ligand per gram of material), used for
determining the stoichiometric amounts of reactants, were the cal-
culated for the idealized composition: 0.3/284.6 = 1.05 mmol/g
32.7 [PPh
2
–Au], ꢀ4.8 m [NP(O
H NMR (CDCl , d ppm): 7.4, 7.2, 6.9 m, br. (arene rings). Solvents
retained (as hexanes) were 2–3%. C { H} NMR (CDCl
154, 135, 122, [OC P], 134, 132, 130, [PPh ] 148, 130 (hidden),
126, 122s [O
2
C
12
H
8
], ꢀ23.7 m [NP(OC
6 4 2 2
H PPh ) ].
1
(
3
1
3
1
2
3
, d ppm):
6
H
4
2
2
C
12
H
8
]. TGA: ꢀ3.3% from the beginning up to 270 °C
(
(
1a), 0.5/322.5 = 1.5 mmol/g (1b), and 0.7/358.5 = 1.9 mmol/g
1c). The average Mw of 1 could not be accurately measured by
(evaporation of solvents), then a continuous loss with maxima at
400 and 485 °C. Residue at 800 °C 54% (teor. AuCl gold content
26.4%). Further heating for ½ h at 800 °C caused an extra loss of
3.6%. DSC: T
similarly obtained in 88% yield. The T
GPC, but they were estimated to be of the order of 700000. The
glass transition temperatures (by DSC) were = 126 °C
= 0.22 J/g K) (1b); 109 °C
= 0.31) (1c). NOTE: Those values may differ in ca. 10 °C
T
g
g
= 176 °C (
D
C
p
= 0.23 J/g K). Complexes 2a and 2c were
(
D
C
C
p
p
= 0.18 J/g K) (1a) [11]; 111 °C (
D
C
p
g
’s were not clearly observed.
(D
depending on the oxidation degree of the phosphines.
2 12 8 6 4 2 2 6 0.5 x n
2.4. Preparation of {[NP(O C H )]1ꢀx[NP(OC H PPh ) (AuPF ) ] }
The IR spectra were recorded with a Perkin–Elmer Paragon
000 spectrometer. Wavenumbers are in cm . NMR spectra were
(3a, 3b)
ꢀ1
1
recorded at room temperature on Bruker NAV-400, DPX-300, AV-
To a solution of 1b (0.25 g, 0.78 mmol, 0.38 mmol PPh
2
) in THF
1
13
1
4
00 and AV-600 instruments H and C{ H} NMR are given in d
(20 mL), [Au(PPh ]PF (0.08 g, 0.09 mmol) was added and the
3
)
2
6
3
1
1
relative to TMS. P{ H} NMR are given in d relative to external
5% aqueous H PO . The C, H, N, analyses were performed with
mixture was refluxed for 15 h. The solvent was evaporated in vac-
uum and the residue was washed with diethyl ether (5 ꢁ 20 mL)
to extract the triphenylphosphine (0.047 g, 0.18 mmol, 98% of the
expected value). The residue was dried overnight in vacuum to give
8
3
4
an Elemental Vario Macro. GPC were measured with a Perkin–El-
mer equipment with a model LC 250 pump, a model LC 290 UV,
and a model LC 30 refractive index detector. The samples were
eluted with a 0.1% by weight solution of tetra-n-buthylammonium
a
white material with idealized formula {[NP(O
[NP(OC PPh (AuPF , (3b, x = 0.25). Yield 0.25 g (88%).
Anal. Calc. for C18
2 12 8
C H )]0.75
6
H
4
2
)
2
6
)
0.5
0.25 n
] }
5
4
bromide in THF through Perkin–Elmer PLGel (Guard, 10 , 10 and
H
13NP1.5
O
2
(AuPF
6
)
0.12 (363.1): C, 59.5; H, 3.61;
3
ꢀ1
1
0 Å) at 30 °C. Approximate molecular weight calibration was ob-
tained using narrow molecular weight distribution polystyrene
standards. T values were measured with a Mettler DSC Toledo
22 differential scanning calorimeter equipped with a TA 1100
N, 3.86. Found: C, 57.6; H, 3.59; N, 3.88%. IR (in cm ; KBr pellets).
ꢀ1
ꢀ
31
1
Like 2 plus two new bands at 837s, 556m, cm ðPF Þ. P{ H}NMR
6
g
(gel state in THF) d (ppm): 42 very broad [PPh
2
–Au], ꢀ4, ꢀ6, ꢀ24
ꢀ
8
broad [NP(O
2
C
12
H8), and OC
H
6 4
PPh
2
], ꢀ144 heptet [PF ]. Weak
6
computer. Thermal gravimetric analysis were performed on a Met-
tler Toledo TG 50 TA 4000 instrument. The polymer samples were
heated at a rate of 10 °C/min from ambient temperature to 800 °C
under constant flow of nitrogen.
sharp signals at ca. 29 were due to the presence of some oxidized
6 4 2
[N@P-OC H P(O)Ph ] units. Those tend to be much intense with
the permanence in solution. TGA: from R.T. to 800 °C a continuous
loss (ꢀ62%) centred at 433 °C. Residue at 800 °C: 38%. Additional
g p
loss 30 min at 800 °C: 1.8%. DSC: T = 159 °C (DC = 0.14 J/g K).
2.2. Preparation of [Au(PPh ) ]PF
3 2 6
The compound 3a was similarly prepared in a 2 grams scale and
9
8% yield from the corresponding phosphazene-phosphine (1a).
To a solution of [Au(THT)Cl] (0.3 g, 0.936 mmol) in THF (30 mL),
PPh (0.59 g, 2.25 mmol) and KPF (0.69 g, 3.75 mmol) were added
and the mixture stirred and refluxed for 2 h. The resulting mixture
was filtered and concentrated to 10 mL. The diethyl ether was
2 6
Anal. Calc. for C15.6H11NP1.38O (AuPF )0.08 (310.35): C, 60.3; H,
3
6
3.54; N, 4.50. Found C, 57.2; H, 3.00; N, 4.36%. TGA: from R.T. to
320 °C a loss of 3% (solvents retained). From 310 to 800 °C a contin-
uous loss (ꢀ53%) centered at 464 °C. Residue at 800 °C: 44%. Addi-
added with stirring to form [Au(PPh
that was washed with ether and dried in vacuo 2 h. Yield: 0.73 g
90%). The compound can be obtained as colourless crystals by
3
)
2
][PF
6
] as a white precipitate
tional loss 30 min at 800 °C: 4%. DSC: T
g
= 170 °C ( = 0.27 J/g K).
D
C
p
(
2.5. Preparation of {[NP(O
(AuPF (4)
C
2 12
H
8
)]0.85[NP(OC PPh ) (AuCl)0.5
6
H
4
2 2
slow diffusion of hexane into a very concentrated dichloromethane
solution in the dark. This procedure avoids the more hazardous
6 0.5 0.15 n
) ] }
TlPF
6
reagent used previously [10].
To a solution of AuCl(THT) (0.039 g, 0.121 mmol) in THF
50 mL), solid 3a (0.5 g, 1.61 mmol, 0.24 mmol of free PPh ) and
the mixture was stirred at room temperature for 2. The H NMR
spectrum of the liquid showed only the presence of un-coordinated
THT. The volatiles were evaporated in vacuum for 1 h to give (4) as
an off-white solid. Yield: 0.52 g (ca. 98%). Anal. Calc. for
(
2
1
2.3. {[NP(O
2
C
H
12 8
)]1ꢀx[NP(OC
6
H
4
PPh
2
2
AuCl) ]
x
}
n
, x = 0.15 (2a), 0.25
(2b), 0.35 (2c)
To a solution of 1b (x = 0.25) (1.5 g, 4.65 mmol, 2.3 mmol of
PPh ) in CH Cl (60 mL), [Au(THT)Cl] (0.70 g, 2.2 mmol) was added
2
2
2
C
15.6
H
11NP1.38
O
2
(AuPF
6
)0.08(AuCl)0.08 (327.8): C, 57.1; H, 3.36; N,
ꢀ1
and the mixture was stirred at room temperature for 15 min. The
mixture was filtered, concentrated in vacuum to about 5 ml and
poured drop wise into hexane (0.5 L) with stirring. The crème-
white precipitate was dried at room temperature in the vacuum
for 3 days to give 2b. Yield 2.0 g (98%). NOTE: Attempts of drying
at 70 °C may cause the formation of small gold nanoclusters as evi-
denced by a pink to violet coloration that, occasionally, may be not
noticed until the compound is dissolved in chloroform. It was also
observed that, as many other Au(I) species, the compound is light
sensitive, specially in chloroform solutions. Anal. Calc. for
4.27. Found: C, 54.7; H, 3.32; N, 4.04%. IR (in cm ; KBr pellets).
ꢀ1
ꢀ
31
Like 3 including the bands at 837s, 556m, cm ðPF Þ. P NMR
6
+
spectrum (gel-suspension in THF): 42 ppm (cationic –Ph
2
P–Au –
PPh
2
– sites), 29 ppm (PPh
2
–AuCl), ꢀ10 ppm, ꢀ25 ppm (P@N units)
ꢀ
and ꢀ145 ppm ðPF Þ.
6
TGA: from R.T. to 273 °C a loss of 4% (solvents retained). From
273 to 800 °C a continuous loss (ꢀ49%) centered at 482 °C. Residue
at 800 °C: 47%. Additional loss 30 min at 800 °C: 4%. DSC:
g p
T = 176 °C (DC = 0.26 J/g K).
18 2
C H13NP1.5O Cl0.5Au0.5 (438.7): C, 49.2; H, 2.96; N, 3.41. Found:
ꢀ
1
C, 48.7; H, 3.19; N, 3.11%. IR (in cm ; KBr pellets) 3057m (
nes), 1588w, 1493m, 1478m, 1436s, 1380–1373m.br., 1263s, sh
PO–C), 1245vs ( NP), 1193vs, 1172vs,sh ( NP), 1096vs (
045w, 1014w, 924vs, br (dPOC), 834m, 785s (dPNP), 750s, 716m,
m
CH, are-
3. Results and discussion
(
1
m
m
m
m
P–OC),
2 12 8
The reaction of the polyphosphazenes {[NP(O C H )]1ꢀx
[NP(OC x = 0.15 (1a), 0.25 (1b), 0.35 (1c)
6
H
4
PPh
2
0
)
2
]
x
}
n
,
ꢀ1
31
1
6
91s, 608m. 586sh, 541s, br cm
.
P{ H}NMR (CDCl
3
, d ppm):
2 12 8
(O C H = 2,2 -dioxybiphenyl), with [Au(THT)Cl] (THT = tetrahy-

G.A. Carriedo et al. / Journal of Organometallic Chemistry 694 (2009) 249–252
251
drothiophene) (1 mmol of Au per mmol of available PPh
in CH Cl at room temperature led to the fast replacement of the
labile THT ligand giving the polymers {[NP(O
NP(OC PPh AuCl) (2a–2c), containing the AuCl group
linked to the main chain by strong phosphine–Au(I) bonds
Scheme 1). The complex 2a (x = 0.15) had been previously
2
groups)
sities of the 31P NMR signals and that could be eliminated by stir-
ring a dichloromethane solution of the complex with mercury. It
was also noticed that, as many other Au(I) species, the compound
is light sensitive, specially in solution, turning pink to violet after
some time.
2
2
2 12 8
C H )]1ꢀx
[
6
H
4
2
2 x n
] }
(
The DSC curves for the polymeric complexes, scanned from 0 °C
to 200 °C did not show a distinct heat capacity jump corresponding
reported [11].
All the data confirmed the composition of the new polymers.
g
to a glass transition except for 2b. As expected, the T value
(176 °C) was higher than those observed for the corresponding
un-coordinated phosphine polymer (111 °C).
Most significantly, the 31P NMR spectra showed, together with
the broad signals of the [NP(O
NP(OC PPh
groups at ca. 33 ppm (that was at ꢀ6.6 ppm in the spectra of the
un-coordinated phosphine polymers). The 13C NMR (Section 2) also
showed the coordination of the gold(I) chloride because the peak
2
C
12
H
8
)] units (near ꢀ5 ppm), and
[
H
6 4
2
] units (near ꢀ24 ppm), the signal of the PPh
2
The use of substoichiometric amounts of [Au(THT)Cl] with re-
2
spect the PPh contents gave the expected partially loaded prod-
ucts in which both phosphine coordinated AuCl and free PPh
2
sites were present. Stirring a dichloromethane solution of those
polymers for 15 min (15 h gave identical results) at room temper-
1 2
corresponding to the C carbon of phenyl rings of the PPh frag-
ment appeared at 132 ppm, while in the free ligand 1 their chem-
ical shift is 138 ppm. The presence of the AuCl in the coordinated
polymers was also evidenced in the solid state IR spectra (KBr pel-
lets) by an slight but noticeable increase of the intensity of the
medium band near 1436 cm relative to that at 1478 cm , as
compared with the found in the spectra of the polymeric free li-
gands 1. The effect can probably be attributed to the influence of
ature in the presence of KPF
6
, lead to the precipitation of insoluble
white materials the IR spectra of which showed the strong absorp-
ꢀ1
ꢀ1
tion at 837 cm and the weak to medium band at 556 cm , cor-
ꢀ
responding to the PF anion. This proves the formation of cationic
6
ꢀ1
ꢀ1
+
sites –Ph
2
P–Au –PPh
2
– giving cross-linked polymeric materials.
However, the yields of the products finally isolated where rather
low (30–50%) and the possibility of incomplete substitution leav-
ing unreacted AuCl sites could not be ruled out. It is very likely,
that the replacement of the Cl ligand at the Au(I) centres, that
might be favoured by the macroligand effect of the polymeric ma-
trix, might be handicapped by the early precipitation of the
product.
the gold atom on the C@C vibrations of the Ph rings of the PPh
2
groups.
Although the AuCl-supported polymers 2 were rather thermally
stable a soft heating at 70 °C under vacuum may cause the forma-
tion of small gold nanoclusters, as evidenced by a pink to violet col-
oration, that occasionally may be unnoticed until the compound is
dissolved in chloroform. We observed that the presence of the
metallic colloidal gold did not alter significantly the relative inten-
Better defined cross-linked polymers with the same cationic
+
–Ph
2
P–Au –PPh
2
–
connections between the chains could be
obtained by the direct reaction of 1, with the gold complex
AuCl
Ph2P
AuCl
PPh2 PPh2
PPh2
O
O
O
O
[
AuCl(THT)]
P
P
P
P
CH Cl . r.t.
N
N
2
2
N
N
1-x
x
n
1-x
x
n
x = 0.15 (1a), 0.25 (1b), x=0.35 (1c)
.
x = 0 15 (2a), 0.25 (2b), 0.35 (2c)
Scheme 1.
N
N
N
P
N
1
-x
P
x
P
O
1
-x
P
x
O
O
O
O
O
O
O
PPh2
PPh
2
PPh2
[
Au(PPh ) ]PF
PPh2
3
2
6
Au PF6-
AuCl(THT)
THF
1
THF reflux
PPh3
ClAu
Au PF6-
-
PPh2
PPh2
O
PPh2
PPh2
O
O
O
O
O
O
O
P
P
P
N
P
N
x
1
-x
N
n
N
x
1
-x
n
3
a (x = 0.15), 3b (x = 0.25)
4
(x = 0.15)
Scheme 2.

2
52
G.A. Carriedo et al. / Journal of Organometallic Chemistry 694 (2009) 249–252
[
Au(PPh
3
)
2
]PF
6
(1 mmol per 4 mmol of available PPh
2
) in refluxing
li-
observed in all the cases, centred in the region of 450 °C. The final
residues at 800 °C (38–47%), that were almost stabilized (further
heating for 30 min resulted in small additional losses of ca. 2–4%)
changed very slightly with the gold contents. As for many other
polyphosphazenes, the main loss is due to the volatilization of or-
ganic compounds during the decomposition [15], and, considering
earlier results [11], the final residues should contain all the gold as
nanoparticles. The high char residues left at 800 °C may also ac-
count for the relative low carbon found in some of the experimen-
tal analysis, which is not unusual with phosphazene materials.
THF (Scheme 2). This process led to the elimination of the PPh
gands and the formation of insoluble materials that were charac-
terized (Section 2) as the polymeric solid matrices of
3
composition
x = 0.15, (3a), 0.25 (3b). The idealized structure proposed for 3
Scheme 2), is based on the regular distribution of the two phosp-
2 12 8 6 4 2 2 6 0.5 x n
{[NP(O C H )]1ꢀx[NP(OC H PPh ) (AuPF ) ] } ,
(
hazenic units present in the starting copolymeric chains of 1. It has
been previously demonstrated that the polymers of this type,
resulting from a macromolecular step-wise substitution from
[
2 n
NPCl ] , behave as perfectly randomized copolymers and the aver-
age chain can be considered as perfectly alternating [13]. As a re-
sult, in the average, the cross-linking sites are regularly
separated by circa 9 units in an open tridimensional matrix that
can be included in the coordination polymers category of the gen-
Acknowledgements
We are grateful to the FYCYT, Project PB-EXPO1-15, and DGI-
CYT, Projects CTQ2004-01484, and CTQ2007-6118, and MAEC-AECI
(M. L. Valenzuela) for financial support.
eral hybrid inorganic–organic framework materials [8].
ꢀ
The IR spectrum confirmed the presence of the PF ion and,
6
3
1
even thought the P NMR spectra (measured in a THF saturated
gel-suspension state) were not well resolved, the presence of a
References
broad weak signal at ca. 42 ppm, evidenced the cationic –Ph
2
P–
– sites. The other less broad signals observed were the
6 4
expected ones for the phosphorus of the NP(O ), NP-OC H -
+
Au –PPh
2
[
1] F. Ciardelli, E. Tsuchida, D. Wöhrle, Macromolecule–Metal Complexes,
Springer, Berlin, 1996.
C
2 12
H
8
and PPh
2
moieties (ꢀ4, ꢀ24 and ꢀ6 ppm, respectively) and the
[2] (a) B.M.L. Dioos, I.F.J. Vankelecom, P.A. Jacobs, Adv. Synth. Catal. 348 (2006)
1413–1446;
ꢀ
[
PF ] anion (ꢀ144 heptet). It was also noticed that, on standing
6
(
b) P.E. Garrou, B.C. Gates, in: D.C. Sherrington, P. Hodge (Eds.), Synthesis and
in solution (but not in the solid state) a sharp signal at 29 ppm ap-
Separation using Functional Polymers, Wiley, New York, 1988, pp. 123–147
(Chapter 3);
peared due to the formation of the oxidized [N@P-OC
units, showing that 3 is rather sensitive to oxygen.
6 4 2
H P(O)Ph ]
(
c) C.U. Pittman Jr., in: G. Wilkinson, F.G.A. Stone, E.W. Abel (Eds.),
Comprehensive Organometallic Chemistry, vol. 8, Pergamon Press, London,
982, pp. 553–611 (Chapter 55).
The DSC of 3 exhibited well defined glass transitions at 170 °C
3a) and 159 °C (3b), showing the expected increase with the frac-
1
(
[3] (a) H.R. Allcock, Chemistry and Applications of Polyphosphazenes, Wiley, New
York, 2003;
tion of the [NP(O
tively). Also consistently, the T
higher than those of the starting linear polymeric phosphines
1a) (126 °C) and (1b) (111 °C) showing the effects of the cationic
C
2 12
H
8
)] groups (1 ꢀ x = 0.85 and 0.75, respec-
(
b) M. Gleria, R. de Jaeger (Eds.), Phosphazenes, Nova Science Publications,
004.
[4] (a) R.A. Dubois, P.E. Garrou, K.D. Lavin, H.R. Allcock, Organometallics 5 (1986)
60–466;
b) H.R. Allcock, K.D. lavin, N.M. Tollefson, T.L. Evans, Organometallics 2 (1983)
65–275;
(c) E. Blaz, J. Pielichowski, Pol. J. Chem. Tech. 8 (2006) 70–72;
d) E. Blaz, J. Pielichowski, Pol. Polimery 51 (2006) 301–304.
5] (a) G.A. Carriedo, J. Chil. Chem. Soc. 52 (2007) 1190–1195;
b) G.A. Carriedo, F.J. García Alonso, P.A. González, P. Gómez Elipe, Polyhedron
8 (1999) 2853–2859.
[6] G.A. Carriedo, F.J. García Alonso, A. Presa, J. Inorg. Organomet. Polym. 14 (2004)
9–37.
7] (a) X. Huang, L. Zhang, Org. Lett. 9 (2007) 4627–4630;
b) B. Guan, D. Xing, G. Cai, X. Wan, N. Yu, Z. Fang, L. Yang, Z. Shi, J. Am. Chem.
g
’s of the solid matrices were
2
4
(
2
(
cross-linking sites.
The reaction leading to 3 is based on the fast free/coordinated
phosphine interchange process that the cationic [Au(PR
plexes undergo in the presence of excess PR
of the polymeric phosphine ligands 2 might be directed to 3 by the
precipitation of these insoluble cross-linked materials.
+
(
3
)
2
] com-
[
3
[14], that, in the case
(
1
2
The insoluble polymeric matrix (3a), that has free PPh
available (functionalization degree FD = 0.48 mmol PPh
2
groups
/gram),
[
2
(
was used to coordinate AuCl groups. Thus, when solid 3a was
Soc. 127 (2005) 18004–18005;
(c) J.J. Kennedy-Smith, S.T. Staben, F.D. Toste, J. Am. Chem. Soc. 126 (2004)
added to a solution of [AuCl(THT)] in THF the 1HNMR spectrum
4
(
526–4527;
d) B.D. sherry, F.D. Toste, J. Am. Chem. Soc. 126 (2004) 15978–15979;
(e) R. Casado, M. Contel, M. Laguna, P. Romero, S. Sanz, J. Am. Chem. Soc. 125
of the liquid revealed the disappearance of the coordinated THT
and the presence of only free THT molecules in solution. The new
insoluble solid obtained had analytical and IR data consistent with
(
(
(
2003) 11925–11935;
f) E. Mizushima, K. Sato, T. Hayashi, M. Tanaka, Angew. Chem., Int. Ed. 41
2002) 4563–4565;
the idealized formula {[NP(O
Cl)0.5(AuPF (4).
Significantly, the IR spectrum showed that a clear increase of
2 12 8 6 4 2 2
C H )]0.85[NP(OC H PPh ) (Au-
6
)
0.5
]
0.15
}
n
(g) E. Boring, Y.V. Geletii, C.L. Hill, J. Am. Chem. Soc. 123 (2001) 1625–1635.
8] A.K. Cheetham, C.N.R. Rao, R.K. Feller, Chem. Commun. (2006) 4780.
[9] R. Usón, A. Laguna, M. Laguna, Inorg. Synth. 26 (1989) 86.
10] R.J. Staples, C. King, M.N.I. Khan, R.E.P. Winpenny, J.P. Fackler Jr., Acta
Crystallogr. Sect C., Cryst. Struct. Commun. C49 (1993) 472–475.
[11] C. Diaz, M.L. Valenzuela, G.A. Carriedo, F.J. García Alonso, A. Presa, Polym. Bull.
57 (2006) 913–920.
[
ꢀ
1
the intensity of the band at 1428 cm
relative to that at
occurred when 3 was transformed in 4, paralleling
the effect of the transformation of 1 in 2 mentioned above. Also
[
ꢀ1
1
478 cm
3
1
consistently, the
P NMR spectrum (gel-suspension in THF)
showed the peaks at 42 ppm (cationic –Ph
[
12] G.A. Carriedo, P. Crochet, F.J. García Alonso, J. Gimeno, A. Presa-Soto, Eur. J.
Inorg. Chem. (2004) 3668–3674.
+
2
2
P–Au –PPh – sites),
2
9 ppm (PPh
2
–AuCl), ꢀ10 ppm and ꢀ25 ppm (P@N units) and
[13] G.A. Carriedo, J.I. Fidalgo, F.J. García Alonso, A. Presa-Soto, C. Diaz Valenzuela,
M.L. Valenzuela, Macromolecules 37 (2004) 9431–9437.
ꢀ
ꢀ
145 ppm ðPF Þ. However, the possibility that some PPh
2
units
6
[
14] R.J. Puddephatt, Gold, in: G. Wilkinson, R.D. Gillard, J.A. McCleverty (Eds.),
Comprehensive Coordination Chemistry, vol. 5, Pergamon Press, Oxford, 2004,
p. 833 (Chapter 55).
were oxidized during the process cannot be completely ruled out.
The thermal stability of the new polymeric materials was stud-
ꢀ1
[15] (a) H.R. Allcock, G.S. Mc Donnell, G.H. Riding, I. Manners, Chem. Mater. (1990)
25;
b) M.T.R. Laguna, M.P. Tarazona, G.A. Carriedo, F.J. García Alonso, J.I. Fidalgo,
E. Saíz, Macromolecules 35 (2002) 7505–7515.
ied by TGA at a heating rate of 10 °C min . A part from a small
occasional first loss (2–4%) centred near 250 °C, corresponding to
the evaporation of solvents retained, a continuous loss was
4
(