Positioning of transition metal centres at the upper rim of cone-shaped calix[4]arenes. Filling the basket with an organometallic ruthenium unit

Article abstract of DOI:10.1039/b110884k

A series of calix[4]arenes bearing diphenylphosphino groups tethered at the upper rim have been prepared by treatment of 5,11,17,23-tetrabromo-25,26,27,28-tetrapropoxycalix[4]arene with Bu^tLi (or BuⁿLi) followed by reaction with PPh₂Cl. The tetraphosphinated derivative 3 was found suitable for the formation of tetranuclear species, notably [3·(AuCl)₄], [3·{RuCl₂(p-cymene)}₄], and [3·{PdCl(o-C₆H₄CH₂NMe₂)} ₄], all possessing an apparent C_4v-symmetry in solution. Reaction of [RuCl₂(p-cymene)]₂ with the diphosphines 5,17-di-X-11,23-bis(diphenylphosphino)-25,26,27,28-tetrapropoxycalix[4]arene (X = H, 1; X = Br, 4) afforded the C_2v-symmetrical dinuclear complexes [1·{RuCl₂(p-cymene)}₂] and [4·{RuCl₂(p-cymene)}₂], respectively. Reaction of the non-brominated diphosphine 1 with [PdCl(o-C₆H₄CH₂NMe₂)]₂ gave the complex [1·{PdCl(o-C₆H₄CH₂NMe₂)} ₂]. Reaction at high dilution of [PtCl₂(1,5-cyclooctadiene)] with 4 or 1 resulted in quantitative formation of the corresponding cis-chelate complexes [4·PtCl₂] (12) and [1·PtCl₂] (13), respectively. The trans version of 13 could also be obtained, provided that [PtCl₂-(PhCN)₂] was used as starting complex. In the solid state, the PtCl₂ unit of 12 is directed towards one bromine atom, resulting in a highly unsymmetrical calixarene structure where the metal plane is nearly parallel to the calix reference plane. The NMR spectra of 12 and 13 show an apparent C_2v-symmetrical structure, suggesting a fast fan-like motion in solution of the metal plane about the P···P axis. Similar dynamics are likely to occur in the related cationic complexes [1·Rh(norbornadiene)]BF₄ (15) and [1·Pd(Me-allyl)]BF₄ (16). As shown by variable temperature studies carried out on 12 and 16, these dynamics couple with a concomitant, restricted rotation of the two PPh₂ units about their coordination axis. The latter motion is probably a result of steric interactions within the phosphorus environment, two PPh rings being in competition for occupation of the cavity entrance. Reaction of the expanded cavity 5,11,17-tribromo-23-diphenylphosphino-25,26,27,28-tetrapropoxycalix[4]arene 5 with [RuCl₂(p-cymene)]₂ afforded the monophosphine complex [5·RuCl₂(p-cymene)]. In solution as well in the solid state, the p-cymene ligand fills the calixarene basket.

Full text of DOI:10.1039/b110884k

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Positioning of transition metal centres at the upper rim of cone-
shaped calix[4]arenes. Filling the basket with an organometallic
ruthenium unit
Manuel Lejeune,a Catherine Jeunesse,a Dominique Matt,*a Nathalie Kyritsakas,b
Richard Welterc and Jean-Pierre Kintzingerd
a Université Louis Pasteur, Laboratoire de Chimie Inorganique Moléculaire, UMR 7513,
1 rue Blaise Pascal, F-67008 Strasbourg Cedex, France. E-mail: dmatt@chimie.u-strasbg.fr
b Université Louis Pasteur, Service de Cristallographie, 4 rue Blaise Pascal,
F-67008 Strasbourg Cedex, France
c Université Louis Pasteur, Laboratoire DECMET, Institut Le Bel, 4 rue Blaise Pascal,
F-67000 Strasbourg Cedex, France
d Université Louis Pasteur, Laboratoire de RMN de la matière condensée, Institut Le Bel,
4 rue Blaise Pascal, F-67070 Strasbourg Cedex, France
Received 27th November 2001, Accepted 26th February 2002
First published as an Advance Article on the web 18th March 2002
A series of calix[4]arenes bearing diphenylphosphino groups tethered at the upper rim have been prepared by
treatment of 5,11,17,23-tetrabromo-25,26,27,28-tetrapropoxycalix[4]arene with ButLi (or BunLi) followed by reaction
with PPh2Cl. The tetraphosphinated derivative 3 was found suitable for the formation of tetranuclear species, notably
[3ؒ(AuCl)4], [3ؒ{RuCl2(p-cymene)}4], and [3ؒ{PdCl(o-C6H4CH2NMe2)}4], all possessing an apparent C4v-symmetry
in solution. Reaction of [RuCl2(p-cymene)]2 with the diphosphines 5,17-di-X-11,23-bis(diphenylphosphino)-
25,26,27,28-tetrapropoxycalix[4]arene (X = H, 1; X = Br, 4) afforded the C2v-symmetrical dinuclear complexes
[1ؒ{RuCl2(p-cymene)}2] and [4ؒ{RuCl2(p-cymene)}2], respectively. Reaction of the non-brominated diphosphine
1 with [PdCl(o-C6H4CH2NMe2)]2 gave the complex [1ؒ{PdCl(o-C6H4CH2NMe2)}2]. Reaction at high dilution of
[PtCl2(1,5-cyclooctadiene)] with 4 or 1 resulted in quantitative formation of the corresponding cis-chelate complexes
[4ؒPtCl2] (12) and [1ؒPtCl2] (13), respectively. The trans version of 13 could also be obtained, provided that [PtCl2-
(PhCN)2] was used as starting complex. In the solid state, the PtCl2 unit of 12 is directed towards one bromine atom,
resulting in a highly unsymmetrical calixarene structure where the metal plane is nearly parallel to the calix reference
plane. The NMR spectra of 12 and 13 show an apparent C2v-symmetrical structure, suggesting a fast fan-like motion
in solution of the metal plane about the P ؒ ؒ ؒ P axis. Similar dynamics are likely to occur in the related cationic
complexes [1ؒRh(norbornadiene)]BF4 (15) and [1ؒPd(Me-allyl)]BF4 (16). As shown by variable temperature studies
carried out on 12 and 16, these dynamics couple with a concomitant, restricted rotation of the two PPh2 units
about their coordination axis. The latter motion is probably a result of steric interactions within the phosphorus
environment, two PPh rings being in competition for occupation of the cavity entrance. Reaction of the expanded
cavity 5,11,17-tribromo-23-diphenylphosphino-25,26,27,28-tetrapropoxycalix[4]arene 5 with [RuCl2(p-cymene)]2
afforded the monophosphine complex [5ؒRuCl2(p-cymene)]. In solution as well in the solid state, the p-cymene
ligand fills the calixarene basket.
Calixarene-derived phosphine ligands have led to an extremely
rich coordination chemistry.1–4 One current development rests
on the anticipation that the covalent linking of such a receptor
to a transition metal centre could lead to supramolecular
catalysts of industrial relevance.4,5 As a first step to this goal we
have recently synthesized a series of complexes in which a metal
unit is fixed in a rigid manner near the upper rim of a calix-
[4]arene kept in the so-called cone conformation. This has led
to several metallo-cavitands where the metal first coordination
sphere is partly sequestered inside the calixarene core.6
Structures of this type were first reported for the 5,17-
diphosphinated calix[4]arene 1, a ligand which readily forms
chelate complexes having trans-arranged phosphorus atoms.
Thus for example, we found that diphosphine 1 reacts with
units were recently used for the partial or total encapsulation of
metal-bonded substrates.7–9 This topic has also been extended
to metallo-cyclodextrins.10
[RuCl2(CO)2]n resulting in a calixarene that contains an
᎐
entrapped Ru–C᎐O fragment. An X-ray study showed that the
In the present study we report on the synthesis and coordin-
ative properties of calixarenes containing one, two or four
phosphino groups tethered at the upper rim of a calix[4]arene.
The directed positioning of transition metal fragments at the
᎐
carbonyl nested inside the cavity is sandwiched between two
facing phenol units separated by only 5.5 Å. Note, other calix-
arene complexes containing non-phosphorus complexing
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J. Chem. Soc., Dalton Trans., 2002, 1642–1650
This journal is © The Royal Society of Chemistry 2002
DOI: 10.1039/b110884k

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cavity entrance is described for some of these ligands, including
a monophosphine derivative which was shown to be suitable
for hosting a (p-cymene)–ruthenium moiety. Furthermore, this
work demonstrates, for the first time, that diphosphine 1 as well
as a related ligand allow cis-chelation across the cavity, resulting
in the formation of highly unsymmetrical calix[4]arenes. It
should be mentioned that related upper-rim phosphinated
calixarenes have been reported recently,5,11,12 but with none of
them was entrapment of metal–organic fragments inside the
cavity achieved. All calixarenes reported herein adopt a cone
conformation. Conformational assignments were made using
well-established rules based on 1H and 13C NMR data.6,13,14
Results and discussion
Introducing P(III) centres on the upper rim of calix[4]arenes
We recently reported a straightforward preparation of tetra-
phosphine 3 which is based on the following two steps: (i)
introduction of four phosphoryl units by reaction of 2 with
Ph2POEt/NiBr2 in refluxing benzonitrile; (ii) reduction of the
thus formed phosphine oxide with PhSiH3.15,16 The phosphoryl-
ation step was inspired by a method originally developed by
Tavs.17 We have now found that 3 may also be prepared in a
convenient one-pot synthesis by stepwise addition to 2 of two
equiv. of ButLi and two equiv. of Ph2PCl, then by repeating
this sequence after 10 h reaction time [eqn. (1)]. This one-pot
procedure afforded 3 in 78% yield (after workup). Attempts to
achieve a direct tetraphosphination using four equiv. of the
reagents (ButLi, PPh2Cl) were not satisfactory, since these
afforded a mixture of compounds in which only small amounts
of 3 were present. Similar observations were recently made by
Harvey et al.18 It is likely that tetralithiation cannot take place
due to steric congestion about the partially lithiated cone inter-
mediate(s) formed once the first amounts of ButLi have been
added. This situation contrasts with the results of Hamada19
and Tsuji20 who found that tetraphosphination using BunLi/
PPh2Cl can be achieved in one step when starting from conform-
ationally non-rigid analogues of 2. However, in this case the
end-product is a mixture of equilibrating conformers. The
molecular structure of tetraphosphine 3 was reported in our
preliminary work.15 Consistent with our findings, the diphos-
phinated compound 4 could be prepared in good yields by
reacting 2 with two equiv. of ButLi and two equiv. of PPh2Cl
[eqn. (2)]. The NMR data of this compound are in full agree-
ment with a C2v-symmetrical molecule. The workup of the
reaction required two recrystallisations in order to eliminate
small quantities of a side product, namely monophosphine 5,
formed in less than 5% yield. The synthesis of the latter could
be improved up to 10% by performing the Br/Li exchange
with BunLi (one equiv.) instead of ButLi. In this case no
diphosphinated product was formed. In keeping with the
sponds to a fast C2v
C2v equilibrium.2 The NMR spectra of
complex 8 revealed that the four PdCl(o-C6H4CH2NMe2)
moieties are equivalent, suggesting that despite the relative
bulkiness of these fragments there is no rotational barrier
about the P–Pd bond. This situation contrasts with that
encountered in a related calix[4]arene complex in which four
“PdCl(o-C6H4CH2NMe2)” moieties, connected to the lower rim
via –CH2PPh2 ligands, do not move freely.21
Attempts to perform, with 3, the synthesis of complexes
having a nuclearity smaller than four, for instance by addition
of sub-stoichiometric amounts of ligand to a starting complex,
only led to mixtures of products that could not be separated.
On the other hand, diphosphines 1 and 4 could be used for the
selective synthesis either of dinuclear or mononuclear com-
plexes. For example, the dinuclear ruthenium complexes 9 and
10 were obtained in high yield from [RuCl2(p-cymene)]2, while
complex 11 was quantitatively formed by reacting 1 with
[PdCl(o-C6H4CH2NMe2)]2. The NMR data of 9–11 are fully
consistent with C2v-symmetrical structures. The suitability of
4 to form mononuclear complexes was first assessed towards
Pt(). Thus reaction of a 10Ϫ5 M dichloromethane solution of
[PtCl2(COD)] (COD = 1,5-cyclooctadiene) or [PtCl2(PhCN)2],
with one equiv. of 4 afforded complex 12 in high yield [eqn. (3)].
When the reaction was not carried out at high dilution, oligo-
meric material was formed, eqn. (4) (see Experimental).
1
presence of a mirror plane, the H NMR spectrum of mono-
Typically for a monomer, the NMR spectra of complex 12
display sharp signals. The observed J(PPt) coupling constant of
3621 Hz is in agreement with cis-arranged phosphorus atoms.
This stereochemistry was confirmed by an X-ray diffraction
study. The cis configuration (PMP angle ca. 100Њ) results in a
highly unsymmetrical calixarene structure (Fig. 1), with the
PtCl2 unit approaching one of the two brominated walls and
the coordination plane being nearly parallel to the calix refer-
ence plane. The calixarene core of 12 is remarkably distorted,
the interplane angle between the ArBr planes being ca. 115Њ; in
comparison, the phenol rings bearing the phosphines are
slightly bent toward the interior of the cavity (dihedral angle:
22Њ). In order to minimize steric interaction with the calixarene
framework, the two phosphino groups do not occupy equiv-
alent positions in the structure. Thus a single phenyl ring fills
the cavity entrance, making the whole structure C1-symmetric
in the solid state. Surprisingly, the 1H and 13C NMR spectra of
12 reveal an apparent C2v-symmetry, which of course is not
phosphine 5 displays three patterns for the m-aryl-H of the
calixarene moiety and two AB systems for the ArCH2
protons. Other valuable NMR data can be inferred from the
Experimental section.
Complexation studies
Ligand 3 defines a complexation domain which, a priori,
appears suitable for maintaining four discrete metal centres in
close proximity, and indeed tetranuclear complexes could be
synthesized from this tetraphosphine. Thus the three complexes
6,
7
and
8
were readily obtained by reacting
3 with
[AuCl(THT)] (THT
=
tetrahydrothiophene), [RuCl2(p-
cymene)]2 and [PdCl(o-C6H4CH2NMe2)]2, respectively. They
1
were characterized by H, 13C and 31P NMR spectroscopy and
elemental analysis (see the Experimental section). As deduced
from the NMR spectra the calixarene units keep the apparent
C4v symmetry found in the free ligand, which actually corre-
J. Chem. Soc., Dalton Trans., 2002, 1642–1650
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Fig. 1 Molecular structure of [PtCl2ؒ4 ] (12). The view also shows the
two CHCl3 solvates that lie close to the PtCl2 unit.
Scheme 1 Proposed motion of the coordination plane in complexes
12, 15 and 16.
Scheme 2 Restricted rotation of the PPh2 groups about the P–Pt
bonds.
within the phosphorus environment, resulting in two PPh rings
(A and AЈ) that compete for occupation of the cavity entrance.
The energy barrier22 for this phenomenon is ∆G≠ = 9.9 kcal
molϪ1
.
It is noteworthy that the trans version of complex 12 could
not be prepared, neither via a direct synthesis, nor by isomeriza-
tion. Interestingly, with the related non-brominated ligand 1,
both stereochemistries, cis and trans, could be obtained. The
selective formation of 13 or 14 [eqns. (5) and (6)] was shown to
depend on the starting complex, [PtCl2(COD)] yielding 13 and
[PtCl2(PhCN)2] affording 14. Again these preparations had to
be carried out at high dilution. The reason why diphosphine 4
selectively results in a cis instead of a trans isomer remains
unclear. It is likely that after coordination of a first P() atom
the bulky bromine atoms of 4 are pushed away from the metal
centre, hence generating a highly flattened calixarene. This in
turn produces a structure with a short P ؒ ؒ ؒ P separation
inappropriate for trans chelation. It is likely that bromine
repulsion from the centre of the cavity is amplified by solvation
consistent with the solid state structure shown in Fig. 1. These
observations suggest that a rapid fan-like motion of the metal
plane about the PP axis takes place in solution, resulting in an
averaged C2v structure (Scheme 1). Interestingly, while the room
temperature 31P NMR (202 MHz) spectrum of 12 displays an
A2X pattern [X = Pt, J(P195Pt) = 3621 Hz], its signals broaden
on lowering the temperature, coalesce at Ϫ40 ЊC, and finally
split into a sharp ABX pattern [J(PPЈ) = 16 Hz, J(P195Pt) ≈ 3530
Hz, J(PЈ195Pt) ≈ 3730 Hz]. The same reduction of symmetry was
1
also observed by H NMR and is consistent with the C1 sym-
metry found in the solid state. A plausible explanation for these
findings is that the two PPh2 units undergo a restricted
(reversible) rotation about their coordination axis as shown in
Scheme 2. This motion is likely to minimize steric interactions
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J. Chem. Soc., Dalton Trans., 2002, 1642–1650

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effects. Note, in the solid state, 4 crystallizes with two CHCl3
molecules that lie close to the PtCl2 unit, each chloride ligand
being associated to a single chloroform solvate (calculated
Cl3CH ؒ ؒ ؒ ClPt separations: 2.78 Å and 2.69 Å, respectively).
Fig. 2 Molecular structure of [Pd(Me-allyl)ؒ1]BF4 (16) (BF4 anion
and CHCl3 solvate not shown).
display significant correlations between the Me(allyl) group and
the aromatic H atoms of the calixarene skeleton. Thus, should a
motion as shown in Scheme 1 occur, then the two exchanging
isomers would probably be unequally populated. Finally,
we noted that on lowering the temperature both the 31P and
1H NMR spectra of 16 first broaden, then coalesce and
eventually become sharp, the patterns being typically that of a
C1-symmetrical calixarene (Fig. 3). These results are consistent
To extend our knowledge on the coordinative properties of
5,17-diphosphinated calixarenes, we also studied the reaction
of diphosphine 1 with the cationic complexes [Rh(nbd)-
(thf )2]BF4 and [Pd(η3-Me-allyl)(thf )2]BF4. These complexes
possess very labile ligands, and are therefore expected to favor
chelation over oligomer formation when reacted with diphos-
phines.23 Indeed these reactions afforded quantitatively com-
plexes 15 and 16, respectively. The two FAB mass spectra
showed the peaks expected for the corresponding [M Ϫ BF4]ϩ
ions. As already observed for 12, the NMR data of 15 are in
keeping with a C2v-symmetrical compound, suggesting the
occurrence of dynamics that displace the rhodium(nbd) unit
from one side of the calixarene to the other (Scheme 1).
Fig. 3 Low temperature 31P NMR spectrum (CD2Cl2, 202 MHz) of
complex 16.
with the PPh2-dynamics already proposed for 12 in Scheme 2.
The free enthalpy of activation is slightly higher than that
found for 12 (∆G≠ = 11.2 kcal molϪ1).
The complexation properties of monophosphine 5 were also
evaluated. Bearing three bromine substituents located at the
upper rim, this calixarene may be regarded as an expanded
calix[4]arene cavity. Its ability to nest an organometallic unit
was checked using [RuCl2(p-cymene)]2. Reaction of this
complex with 5 afforded 17 in 85% yield [eqn. (7)] which was
characterized by a single crystal X-ray diffraction study.
As shown in Fig. 4, the Ru–P vector pointing towards the
calixarene axis, and hence the “RuCl2(p-cymene)” unit, sits
within the four upper rim substituents (Br, Br, Br, P). Incidently,
one end of the p-cymene ligand lies inside the deepened cavity.
The partial encapsulation of the “RuCl2(p-cymene)” moiety
For complex 16, the solid state structure of which is shown in
Fig. 2, the interpretation of the NMR spectra is made more
difficult owing to the presence of an allyl group. In this case the
room temperature spectrum reveals an apparent Cs-symmetry
which in fact is consistent both with a static structure as found
in the solid state, as well as a fluxional structure in which the
metal plane oscillates rapidly about the P ؒ ؒ ؒ P axis, provided
that there is no “allyl rotation”. This latter point was confirmed
by ROESY experiments. Hence we have no definitive answer to
the question whether the metal plane moves as shown in
Scheme 1, although this hypothesis seems very reasonable. It
should be mentioned that the 2D ROESY spectrum does not
1
persists in solution, as deduced from the H NMR spectrum
which shows that the MeC6H4Pri group as well as the neigh-
bouring ortho-protons, both apically sited above two facing
J. Chem. Soc., Dalton Trans., 2002, 1642–1650
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In the solid state, the Ar–Me bond of the p-cymene ligand is
oriented sideways, pointing towards a bromine atom, thus
probably minimizing steric interaction between the Ar–Me
group and the two phenol rings that sandwich the p-cymene
ring. Interestingly, in the related complex 18 where the calix
cone is shorter, the coordinated RhCp*Cl2 unit (Cp* = C5Me5)
lies completely outside the cavity.11 It is likely that for steric
reasons the PPh rings of the bulky ligand 5 are oriented out-
wards, resulting in a phosphorus lone pair that points to the
calix axis and which in turn forces metal complexation to occur
at the cavity entrance. Overall the entrapment of the p-cymene
unit may be regarded as a mechanical imprisonment within
enlarged calixarene walls.
Conclusions
We have described a synthetic methodology that allows single
or multiple phosphination at the upper-rim of calix[4]arenes.
Multiple complexation was achieved with the di- and tetra-
phosphinated ligands resulting in complexes where the metal
units are all maintained close to the upper rim. When behaving
as chelators the 5,17-diphosphinated ligands 1 and 4 position
the complexed metal centre exactly at the cone entrance. The
fact that 1 and 4 may act as cis-chelators is rather unexpected in
view of the high asymmetry generated in the resulting struc-
tures. Their dynamic behaviour in solution is probably a
response to the steric strain induced in these calixarenes.
The most interesting feature of the “expanded” cavity 5
concerns the possibility to realize partial entrapment of
coordinated metal units. Future work is aimed at exploiting
this property for catalytic processes occurring inside a spatially-
restricted environment.
Fig. 4 Molecular structure of complex 17: left, ball and stick
representation; right, CPK model showing the enveloped “RuCl2(p-
cymene)” unit in red (CH2Cl2 and hexane solvates are not shown).
Experimental
All manipulations involving phosphines were performed in
Schlenk-type flasks under dry nitrogen. Solvents were dried by
conventional methods and distilled immediately prior to use.
CDCl3 was passed down a 5 cm-thick alumina column and
1
Fig. 5 1H NMR spectra (CDCl3, partial view) of the ruthenium
complexes 10 and 17.
stored under nitrogen over molecular sieves (4 Å). Routine H
and 31P{1H} spectra were recorded with FT Bruker instruments
(AC-300 or Bruker AM-400). 13C{1H} were recorded with an
1
FT Bruker AC-200 spectrometer. H NMR spectra were refer-
phenoxy rings, have undergone a highfield shift of ca. 1 ppm (!)
when compared to the values found in 7, 9 and 10 (Fig. 5). In
contrast, the meta-H atoms and the Pri protons have normal
chemical shifts (see Experimental), suggesting that the p-cymene
ring undergoes restricted rotation about its coordination axis as
shown in Scheme 3.
enced to residual protio solvents (7.26 ppm for CDCl3 and 5.32
ppm for CD2Cl2), 13C chemical shifts are reported relative to
deuterated solvents (77.0 ppm for CDCl3 and 53.8 ppm for
CD2Cl2), and the 31P NMR data are given relative to external
H3PO4. Mass spectra were recorded on a ZAB HF VG
analytical spectrometer using m-nitrobenzyl alcohol as matrix.
ButLi and BunLi solutions were titrated according to a
conventional method.24 5,11,17,23-Tetrabromo-25,26,27,28-
tetrapropoxycalix[4]arene (2),25 [AuCl(THT)],26 [Pd(o-C6-
H4CH2NMe2)Cl]2,27 [RuCl2(p-cymene)]2,28 [PtCl2(COD)],29
[PtCl2(PhCN)2],30 [RhCl(norbornadiene)]2,31 [Pd(η3-C4H7)Cl]2,32
were prepared according to methods reported in the literature.
In the NMR data “Cq” denotes a quaternary carbon atom. In
the following “dmba” stands for the o-C6H4CH2NMe2 ligand.
Scheme 3 Restricted rotation of the p-cymene unit about its coordin-
ation axis.
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J. Chem. Soc., Dalton Trans., 2002, 1642–1650

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Syntheses
of BunLi–hexane (4.0 cm3, 6.1 mmol). After 1 h, neat Ph2PCl
(1.0 cm3, 5.5 mmol) was added and the solution was maintained
at Ϫ78 ЊC for 10 h. The solution was then stirred for a further
5 h at room temperature. The solvent was removed and the
residue was taken up with CH2Cl2. Addition of MeOH afforded
a white precipitate which was purified by column chrom-
atography (Rf = 0.3, SiO2, CH2Cl2–hexane 80 : 20 v/v). Yield:
5,17-Bis(diphenylphosphino)-25,26,27,28-tetrapropoxycalix-
[4]arene 1. To a cold (Ϫ78 ЊC) solution of 2 (2.169 g,
2.38 mmol) in THF (50 cm3) was added a 1.72 M solution of
ButLi-pentane (2.8 cm3, 4.8 mmol). After 1 h, Ph2PCl (0.8 cm3,
1.053 g, 4.76 mmol) was added dropwise and the solution was
stirred for 10 h at Ϫ78 ЊC. The lithiation step was then repeated
using the same amounts of ButLi. The reaction was quenched
with MeOH (3 cm3). The solution was allowed to warm up to
room temperature, evaporated to dryness and the residue was
taken up with CH2Cl2. Addition of EtOH afforded a white
precipitate. Yield: 1.875 g, 82%. mp > 280 ЊC. 1H NMR
(CDCl3): δ 7.37–7.33 (20H, PPh2), 7.06 [d, 4H, m-H of OArP,
3J(PH) = 8 Hz], 6.29 and 6.11 (AB2 spin system, 6H, m and p-H
1
0.498 g, 10%. H NMR (CDCl3): δ 7.42–7.26 (m, 10H, PPh2),
7.13 (s, 2H, m-H of OArBr), 6.90 [d, 2H, m-H of OArP, 3J(PH)
= 7.3 Hz], 6.62 and 6.53 [2d, AB spin system, 4H, m-H of
4
OArBr, J(AB) = 2.7 Hz], 4.40 and 3.11 [2d, AB spin system,
2
4H, ArCH2Ar, J(AB) = 13.8 Hz], 4.39 and 3.07 [2d, AB spin
2
system, 4H, ArCH2Ar, J(AB) = 13.9 Hz], 3.99–3.92 (2 over-
lapped m, 6H, OCH2 of OArP), 3.77–3.72 (2 overlapped t, 6H,
OCH2 of OArBr), 1.95–1.87 (m, 8H, OCH2CH2), 1.05, 0.97 and
0.95 (3 overlapped t, 12H, CH3). 13C{1H} NMR (CDCl3):
δ 158.69, 157.11 and 155.80 (3s, arom. Cq–O), 138.58–129.45
(arom. C’s), 116.27 and 115.88 (2s, arom. Cq–Br), 78.11 (3 ×)
and 77.75 (2s, OCH2), 31.70 (s, ArCH2Ar), 24.16 and 23.83 (2s,
CH2CH3), 11.44, 10.98 and 10.88 (3s, CH3). 31P{1H} NMR
(CDCl3): δ Ϫ6.2 (s, PPh2). Found: C, 61.47; H, 5.66. Calc. for
C52H54Br3O4P (Mr = 1013.67) C, 61.61; H, 5.37%.
3
of OAr, J = 8 Hz), 4.41 and 3.06 [2d, AB spin sytem, 8H,
ArCH2Ar, 2J(AB) = 13.0 Hz], 4.03 (pseudo t, 4H, OCH2, 3J ≈ 8
3
Hz), 3.63 (t, 4H, OCH2, J = 8 Hz), 2.00 (m, 4H, OCH2CH2),
1.81 (m, 4H, OCH2CH2), 1.06 (t, 6H, CH3, 3J = 7.5 Hz), 0.91 (t,
6H, CH3, J = 7.5 Hz). 13C{1H} NMR (CDCl3): δ 159.80 and
3
155.10 (2s, arom. Cq–O), 137.25–122.02 (arom. C’s), 77.00 and
76.60 (2s, OCH2), 30.95 (s, ArCH2Ar), 23.51 and 23.15 (2s,
CH2CH3), 10.82 and 9.93 (2s, CH3). 31P{1H} NMR (CDCl3):
δ Ϫ6.4 (s, PPh2). Found: C, 80.18; H, 6.74. Calc. for C64H66O4P2
(Mr = 961.18) C, 79.98; H, 6.92%.
Tetrachloro{5,11,17,23-tetra(diphenylphosphino)-25,26,27,28-
tetrapropoxycalix[4]arene}gold(I) 6. A solution of [AuCl(tht)]
(0.097 g, 0.30 mmol) in THF (1 cm3) was added to a solution of
3 (0.100 g, 0.08 mmol) in CH2Cl2 (15 cm3). After stirring for 2 h
the solution was filtered over Celite and the filtrate was concen-
trated to ca. 1 cm3. Addition of hexane afforded the complex
as a white powder. Yield: 0.120 g, 75%. mp 242–245 ЊC (dec.).
1H NMR (CDCl3): δ 7.62–7.55 and 7.45–7.37 (24H, PPh2),
7.15, 7.11 and 7.00 (3d, 24H, arom. H’s PPh2 and calix), 4.51
and 3.20 [AB spin sytem, 8H, ArCH2Ar, 2J(AB) = 13 Hz],
5,11,17,23-Tetrakis(diphenylphosphino)-25,26,27,28-tetra-
propoxycalix[4]arene 3. To a cold (Ϫ78 ЊC) solution of 2
(2.169 g, 2.38 mmol) in THF (50 cm3) was added a 1.72 M
solution of ButLi–pentane (3.0 cm3, 4.8 mmol). After 1 h,
Ph2PCl (0.8 cm3, 1.053 g, 4.76 mmol) was added and the
solution was stirred for 10 h at Ϫ78 ЊC. This lithiation/
phosphination step was then repeated using the same amounts
of ButLi and Ph2PCl. The solution was warmed up to room
temperature, evaporated to dryness and the residue was taken
up with CH2Cl2. Addition of EtOH afforded a white precip-
3
3.99 (t, 8H, OCH2, J = 8 Hz), 1.98 (m, 8H, OCH2CH2), 1.02
3
(t, 12H, CH3, J = 7.5 Hz). 13C{1H} NMR (CDCl3): δ 159.45
1
(s, arom. Cq–O), 135.62–121.43 (arom. C’s), 77.59 (s,
OCH2), 31.53 (s, ArCH2Ar), 23.20 (s, CH2CH3), 10.23 (s, CH3).
31P{1H} NMR (CDCl3): δ 31.12 (s, PPh2). Found: C, 48.68;
H, 3.95. Calc. for C88H84Cl4O4P4Au4ؒC6H14 (Mr = 2259.22 ϩ
86.17) C, 48.14; H, 4.21%. This complex slowly decomposes in
solution.
itate. Yield: 2.468 g, 78 %. mp > 280 ЊC. H NMR (CDCl3):
δ 7.28–7.23 and 7.07–7.02 (40H, PPh2), 6.74 [d, 8H, m-H of
OArP, 3J(PH) = 7.9 Hz], 4.41 and 3.05 [2d, AB spin system, 8H,
ArCH2Ar, 2J(AB) = 13.0 Hz], 3.87 (t, 8H, OCH2, 3J = 8.0 Hz),
1.95 (m, 8H, OCH2CH2), 0.98 (t, 12H, CH3, 3J = 7.5 Hz).
13C{1H} NMR (CDCl3): δ 159.48 (s, arom. Cq–O), 135.03–
124.73 (arom. C’s), 76.47 (s, OCH2), 31.31 (s, ArCH2Ar), 23.15
(s, CH2CH3), 10.15 (s, CH3). 31P{1H} NMR (CDCl3): δ Ϫ6.0
(s, PPh2). Found: C,79.41; H, 6.53. Calc. for C88H84O4P4
(Mr = 1329.54) C, 79.50; H, 6.37%.
Tetra(dichloro)tetra(ꢀ6-p-cymene)[5,11,23,17-tetra(diphenyl-
phosphino)-25,26,27,28-tetrapropoxycalix[4]arene]tetra-
ruthenium(II) 7. A solution of [RuCl2(p-cymene)]2 (0.050 g,
0.084 mmol) in CH2Cl2 (10 ml) was added to a solution of
tetraphosphine 3 (0.056 g, 0.042 mmol) in CH2Cl2 (30 ml).
After stirring for one night, the solution was evaporated to
dryness and the residue was taken-up with CHCl3. Addition of
Et2O afforded an orange precipitate. Yield: 0.076 g, 81%. mp
5,17-Dibromo-11,23-bis(diphenylphosphino)-25,26,27,28-
tetrapropoxycalix[4]arene 4. To a solution of 2 (10.080 g, 11.1
mmol) in THF (50 cm3) at Ϫ78 ЊC was added dropwise a 1.72 M
solution of ButLi–pentane (12.9 cm3, 22.2 mmol). After 1 h,
Ph2PCl (3.8 cm3, 22.2 mmol) was added and the solution was
stirred for a further 10 h at Ϫ78 ЊC. The solvent was evaporated
and the residue was taken up with CHCl3. Addition of MeOH
1
236 ЊC. H NMR (300 MHz, 298 K, CDCl3): δ 7.49–7.00 (m,
48H, PPh2 and m-H of calixarene), 5.29 and 5.05 [2d, AAЈBBЈ
3
3
spin system, 16H, C6H4 of p-cymene J(AB) = J(AЈBЈ) = 6.0
Hz], 4.48 and 3.19 [2d, AB spin system, 8H, ArCH2Ar, 2J(AB) =
12.9 Hz], 3.97 (t, 8H, OCH2 of OArP, 3J = 6.7 Hz), 2.6 [m, 4H,
CH(CH3)2], 1.85 (m, 8H, OCH2CH2), 1.00 [d, 6H, CH(CH3)2,
3J = 6.7 Hz], 0.91 (t, 12H, CH3, 3J = 7 Hz). 31P{1H} NMR (121
MHz, 298 K, CDCl3): δ 21.7 (s, PPh2). Found: C, 59.93; H,
5.48. Calc. for C128H140Cl8O4P4Ru4 (Mr = 2554.33): C, 60.19;
H, 5.52%.
1
afforded a white precipitate. Yield: 7.9 g, 63%. mp 256 ЊC. H
NMR (CDCl3): δ 7.51–7.37 (20H, PPh2), 7.12 [d, 4H, m-H of
OArP, 3J(PH) = 7.5 Hz], 6.37 (s, 4H, m-H of OArBr), 4.40 and
2
3.07 [2d, AB spin system, 8H, ArCH2Ar, J(AB) = 13.3 Hz],
3
3
4.07 (t, OCH2, J = 8.0 Hz), 3.62 (t, 4H, OCH2, J = 6.7 Hz),
1.99 (m, 4H, OCH2CH2), 1.85 (m, 4H, OCH2CH2), 1.08 (t, 6H,
CH3, 3J = 7.5 Hz), 0.92 (t, 6H, CH3, 3J = 7.4 Hz). 13C{1H} NMR
(CDCl3): δ 158.40 and 154.27 (2s, Cq–O), 138.10–128.58 (arom.
C’s), 115.38 (s, CBr), 77.35 and 76.74 (2s, OCH2), 30.85 (s,
ArCH2Ar), 23.43 and 23.08 (2s, CH2CH3), 10.77 and 9.79 (2s,
CH3). 31P{1H} NMR (CDCl3): δ Ϫ6.6 (s, PPh2). Found: C,
68.45; H, 5.78. Calc. for C64H64Br2O4P2 (Mr = 1118.98) C, 68.70;
H, 5.77%.
Tetrachloro-tetra(N,N-dimethylaminobenzylamine){5,11,17,
23-tetra(diphenylphosphino)-25,26,27,28-tetrapropoxycalix[4]-
arene}tetrapalladium(II) 8. A solution of [Pd(o-C6H4NMe2)Cl]2
(0.067 g, 0.12 mmol) in THF (1 cm3) was added to a solution of
the tetraphosphine 3 (0.080 g, 0.06 mmol) in CH2Cl2 (15 cm3).
After stirring for 2 h the solution was filtered over Celite and
the filtrate was concentrated to ca. 1 cm3. Addition of pentane
afforded the complex as a white precipitate. Yield: 0.120 g, 77%.
5,11,17-Tribromo-23-diphenylphosphino-25,26,27,28-tetra-
propoxycalix[4]arene 5. To a solution of 2 (5.010 g, 5.51 mmol)
in THF (150 cm3, Ϫ78 ЊC) was slowly added a 1.5 M solution
1
mp 208–212 ЊC (dec.). H NMR (CDCl3): δ 7.43–7.20 (48H,
J. Chem. Soc., Dalton Trans., 2002, 1642–1650
1647

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m-H of OAr and PPh2), 6.25 and 5.97 (16H, arom H of dmba),
4.24 and 2.79 [AB spin sytem, 8H, ArCH2Ar, 2J(AB) = 13 Hz],
3.91(s, 8H, NCH2 of dmba), 3.81 (t, 8H, OCH2, J = 7.8 Hz),
diphosphine 1 (0.130 g, 0.13 mmol) in CH2Cl2 (20 cm3). After
stirring for 1 h the solution was concentrated to ca. 1 cm3.
Addition of hexane afforded complex 11 as a white precipitate.
Yield: 0.150 g, 75%. mp 220–222 ЊC. 1H NMR (CDCl3): δ 7.81–
7.7 and 7.45–7.37 (20H, PPh2), 7.61 [d, 4H, m-ArH of OArP,
3J(PH) = 11.6 Hz], 7.07–6.92 and 6.65–6.49 (8H, arom H of
dmba), 6.05 and 5.64 (d and t, AB2 spin system, 6H m-H and
3
2.64 (d, 24H, NCH3 of dmba, J = 2.1 Hz), 1.74 (m, 8H,
3
OCH2CH2), 0.87 (t, 12H, CH3, J = 7.3 Hz). 13C{1H} NMR
(CDCl3): δ 158.24 (s, arom. Cq–O), 152.32 and 148.44 (2s, Cq of
dmba), 137.88–122.17 (arom. C’s), 76.44 (s, OCH2), 73.33
(s, NCH2 of dmba), 50.39 (s, NCH3 of dmba), 32.14 (s,
ArCH2Ar), 22.78 (s, CH2CH3), 10.24 (s, CH3). 31P{1H} NMR
(CDCl3): δ 40.27 (s, PPh2). Found: C, 61.68; H, 5.46; N, 2.26.
Calc. for C124H132Cl4N4O4P4Pd4 (Mr = 2575.58): C, 61.20; H,
5.47; N, 2.30%.
3
p-H of OAr, J = 7.6 Hz), 4.39 and 3.04 [AB spin sytem, 8H,
ArCH2Ar, 2J(AB) = 13.4 Hz], 4.05 (t, 4H, OCH2, 3J = 7.5 Hz),
4.04 [d, 4H, NCH2 of dmba, 4J(PH) = 2 Hz], 3.57 (t, 4H, OCH2,
3J = 6.6 Hz), 2.90 (d, 12H, NCH3 of dmba, 4J = 2.4 Hz), 2.02–
1.77 (m, 8H, OCH2CH2), 1.08 and 0.93 (2t, 12H, CH3, 3J = 7.3
Hz). 13C{1H} NMR (CDCl3): δ 160.51 and 154.91 (2s, arom.
Cq–O), 151.4 and 148.1 (2s, Cq of dmba), 136.37–122.42 (arom.
C’s), 77.35 and 76.50 (2s, OCH2), 73.25 (s, NCH2), 50.52
(s, NCH3), 31.00 (s, ArCH2Ar), 23.55 and 23.18 (2s, CH2CH3),
10.85 and 9.86 (2s, CH3). 31P{1H} NMR (CDCl3): δ 42.62 (s,
PPh2). Found: C, 65.77; H, 5.68. Calc. for C82H90Cl2N2O4P2Pd2
(Mr = 1513.30): C, 65.08; H, 5.68%.
Bis(dichloro)bis(ꢀ6-p-cymene)[5,17-bis(diphenylphosphino)-
25,26,27,28-tetrapropoxycalix[4]arene]diruthenium(II) 9.
A
solution of [RuCl2(p-cymene)]2 (0.096 g, 0.16 mmol) in CH2Cl2
(10 cm3) was added to a solution of diphosphine 1 (0.150 g, 0.16
mmol) in CH2Cl2 (30 cm3). After stirring for 1 h the solution
was concentrated to ca. 5 cm3 and addition of diethyl ether
afforded an analytically pure orange powder. Yield: 0.165 g,
67%. mp 192–194 ЊC. 1H NMR (CD2Cl2): δ 7.97–7.87 and 7.43–
cis-P,PЈ-Dichloro{5,17-dibromo-11,23-bis(diphenylphos-
phino)-25,26,27,28-tetrapropoxycalix[4]arene}platinum(II) 12. A
solution of diphosphine 4 (0.167 g, 0.15 mmol) in CH2Cl2 (250
cm3) and a solution of [PtCl2(COD)] (0.056 g, 0.15 mmol) in
CH2Cl2 (250 cm3) were added simultaneously into a 2 L flask
contaning 750 cm3 of CH2Cl2 over a period of 4 h. The result-
ing solution was stirred overnight at room temperature. The
solution was concentrated to ca. 5 cm3. Addition of toluene
afforded a white precipitate. Yield: 0.183 g, 90%. mp > 280 ЊC.
1H NMR (CDCl3): consistent with the formation of a mono-
mer, all signals are sharp: δ 7.28–7.03 (m, 24 H, PPh2 and m-H
of OArP), 6.91 (broad s, 4H, m-H of OArBr), 4.49 and 3.21 [2d,
AB spin system, 8H, ArCH2 Ar, 3J(AB) = 13.7 Hz], 4.08 (t, 4H,
OCH2 of OArP, 3J = 8.1 Hz), 3.80 (t, 4H, OCH2 of OArBr, 3J =
6.3 Hz), 1.95–1.88 (m, 8H, OCH2 CH2), 1.16 and 0.89 (2t, 12H,
CH3, 3J = 7.0 Hz). 13C{1H} NMR (CDCl3): δ 157.87 and 156.56
(2s, arom. Cq–O), 138.40–125.36 (arom. C’s), 116.32 (s, arom.
Cq–Br), 77.42 and 77.08 (2s, OCH2), 31.13 (s, ArCH2Ar), 23.63
and 22.78 (2s, CH2CH3), 10.89 and 9.77 (2s, CH3). 31P{1H}
(CDCl3): δ 11.2 [s with Pt satellites, PPh2, J(PPt) = 3621 Hz].
FAB mass spectrum: m/z (%) 1349.2 (100) [M Ϫ Cl]ϩ, 1313.1
(62) [M Ϫ 2Cl]ϩ. Found: C, 54.29; H, 4.82. Calc. for
C64H64Br2Cl2O4P2Ptؒ0.5CH2Cl2 (Mr = 1384.97 ϩ 42.47): C,
54.27; H, 4.59%.
3
7.40 (m, 20H, PPh2), 7.58 [d, 4H, m-ArH of OArP, J(PH) =
10.4 Hz], 6.20 and 5.98 (d and t, AB2 spin system, m-H and p-H
3
of OAr, J = 7.5 Hz), 5.25 and 5.11 [2d, AAЈBBЈ spin system,
3
3
8H, C6H4 of p-cymene J(AB) = J(AЈBЈ) = 5.3 Hz], 4.37 and
3.08 (2d, AB spin system, 8H, ArCH2, 2J = 13.2 Hz), 4.05 (t, 4H,
OCH2 of OArP, 3J = 6.9 Hz), 3.57 (t, 4H, OCH2 of OArBr, 3J =
6.7 Hz), 2.85 [hept., 2H, CH(CH3)2 of p-cymene], 1.95 (s, 6H, p-
Me of p-cymene), 2.00–1.75 (2m, 8H, OCH2CH2), 1.13 [d, 6H,
3
3
CH(CH3)2, J = 6.9 Hz], 1.06 and 0.89 (2t, 12H, CH3, J = 7.6
Hz). 13C{1H} NMR (CDCl3): δ 160.09 and 154.94 (2s, arom.
Cq–O), 136.89–122.25 (arom. C’s), 110.50 and 95.89 (2s, arom.
Cq’s of p-cymene), 89.35 and 86.91 (2s, arom. CH of p-cymene),
77.70 and 77.07 (2s, OCH2), 30.98 (s, ArCH2Ar), 30.32 (s,
CH(CH3)2), 23.51 and 23.18 (2s, CH2CH3), 17.86 (s, ArCH3 of
p-cymene), 10.88 and 9.85 (2s, CH3). 31P{1H} NMR (CDCl3):
δ 22.99 (s, PPh2). Found: C, 64.14; H 6.23. Calc. for
C84H94Cl4O4P2Ru2 (Mr = 1573.58): C, 64.12; H, 6.02%.
Bis(dichloro)bis(ꢀ6-p-cymene)[5,17-(dibromo)-11,23-bis-
(diphenylphosphino)-25,26,27,28-tetrapropoxycalix[4]arene]-
diruthenium(II) 10. A solution of [RuCl2(p-cymene)]2 (0.030 g,
0.05 mmol) in CH2Cl2 (10 cm3) was added to a solution of
diphosphine 4 (0.056 g, 0.05 mmol) in CH2Cl2 (30 cm3). After
stirring for one night the solution was concentrated to ca. 5 cm3.
Addition of diethyl ether afforded an analytically pure orange
powder. Yield: 0.081g, 90 %. mp 226–230 ЊC. 1H NMR
(CDCl3): δ 7.95–7.89 and 7.50–7.41 (m, 20H, PPh2), 7.55 [d, 4H,
m-ArH of OArP, 3J(PH) = 10.0 Hz], 6.24 (s, 4H, m-H of
OArBr), 5.29 and 5.05 [2d, AAЈBBЈ spin system, 8H, C6H4 of
Oligomer [PtCl2ؒ4]n. A solution of [PtCl2(COD)] (0.078 g,
0.20 mmol) in CH2Cl2 (5 cm3) was added to a stirred solution of
4 (0.220 g, 0.20 mmol) in CH2Cl2 (5 cm3). After stirring over-
night, the solution was concentrated to ca. 2 cm3 and addition
of diethyl ether afforded a white precipitate. Yield: 0.195 g,
3
3
1
p-cymene J(AB) = J(AЈBЈ) = 6.0 Hz], 4.33 and 3.06 [2d, AB
95%. mp > 280 ЊC. H NMR (400 MHz, 388 K, C2D2Cl4): the
2
spin system, 8H, ArCH2Ar, J(AB) = 13.4 Hz], 4.04 (t, 4H,
following signals are typically broad for an oligomer: δ 7.70–
7.65 and 7.45–7.38 (2m, 24H, PPh2 and m-H of OArP), 6.14 (s,
4H, m-H of OArBr), 4.37 and 3.03 [2d, AB spin system, 8H,
ArCH2Ar, 2J(AB) = 13.4 Hz], 4.12 (t, 4H, OCH2 of OArP, 3J =
OCH2 of OArP, 3J = 8.3 Hz), 3.56 (t, 4H, OCH2 of OArBr, 3J =
6.7 Hz), 2.9 [m, 2H, CH(CH3)2 of p-cymene], 1.97 (s, 6H, p-Me
of p-cymene), 1.95 and 1.80 (2m, 8H, OCH2CH2), 1.14 [d, 6H,
3
3
3
CH(CH3)2, J = 6.6 Hz], 1.05 and 0.88 (2t, 12H, CH3, J = 7.3
Hz). 13C{1H} NMR (CDCl3): δ 160.45 and 155.08 (2s, arom.
Cq–O), 136.72–129.21 (arom. C’s), 116.20 (s, arom. Cq–Br),
112.04 and 97.06 (2s, arom. Cq’s of p-cymene), 89.65 and 88.47
(2s, arom. CH of p-cymene), 78.29 and 77.65 (2s, OCH2), 31.82
[s, CH(CH3)2], 31.27 (s, ArCH2Ar), 24.29 and 22.9 (2s,
CH2CH3), 19.01 (s, ArCH3 of p-cymene), 11.73 and 10.65 (2s,
CH3). 31P{1H} NMR (CDCl3): δ 24.08 (s, PPh2). Found: C,
58.04; H, 5.00. Calc. for C84H92Br2Cl4O4P2Ru2 (Mr = 1731.37):
C, 58.27; H, 5.36%.
7.1 Hz), 3.68 (t, 4H, OCH2 of OArBr, J = 5.6 Hz), 1.93–1.85
(m, 8H, OCH2CH2), 1.12 and 0.95 (2t, 12H, CH3, 3J = 7.3 Hz).
13C{1H} NMR (CD2Cl2): δ 160.87 and 154.86 (2s, arom. Cq–O),
136.86–128.66 (arom. C’s), 115.61 (s, arom. Cq–Br), 77.98 and
77.31 (2s, OCH2), 31.26 (s, ArCH2Ar), 23.83 and 23.52 (2s,
CH2CH3), 11.09 and 9.95 (2s, CH3). 31P{1H}NMR (CDCl3):
δ 13.7 [s with Pt satellites, PPh2, J(PPt) = 3660 Hz]. Molecular
weight determination by osmometry (CH2Cl2): 14000
90,
corresponding to a formal value of n = 10. FAB mass spectrum:
m/z (%) 1349.5 (10) [M Ϫ Cl], 1312.7 (100) [M Ϫ 2Cl]. Found:
C, 55.60; H, 4.41. Calc. for [C64H64Br2Cl2O4P2Pt]n (Mr = n ×
1384.97): C, 55.60; H, 4.66%.
Dichloro-bis(N,N-dimethylaminobenzylamine){5,17-bis-
(diphenylphosphino)-25,26,27,28-tetrapropoxycalix[4]arene}-
dipalladium(II) 11. A solution of [Pd(o-C6H4NMe2)Cl]2 (0.075
g, 0.13 mmol) in CH2Cl2 (5 cm3) was added to a solution of
cis-P,PЈ-Dichloro{5,17-bis(diphenylphosphino)-25,26,27,28-
tetrapropoxycalix[4]arene}platinum(II) 13.
A
solution of
1648
J. Chem. Soc., Dalton Trans., 2002, 1642–1650

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diphosphine 1 (0.150 g, 0.16 mmol) in CH2Cl2 (250 cm3) and a
solution of [PtCl2(COD)] (0.059 g, 0.16 mmol) in CH2Cl2 (250
cm3) were added simultaneously into a 2 L flask containing 750
cm3 of CH2Cl2 over a period of 4 h. The resulting solution was
stirred for 15 h at room temperature. The solution was concen-
trated to ca. 5 cm3 and addition of pentane afforded 13 as a
31P{1H} NMR (CDCl3): δ 24.6 [d, PPh2, J(PRh) = 156 Hz]. FAB
mass spectrum: m/z (%) 1258.4 (3) [M Ϫ O]ϩ, 1171.5 (43) [M Ϫ
BF4 ϩ O]ϩ, 1155.55 (38) [M Ϫ BF4]ϩ. Found: C, 68.83; H, 6.19.
Calc. for C71H74BF4O4P2Rh (Mr = 1243.04): C, 68.61; H, 6.00%.
(ꢀ3-2-Methylallyl){P,PЈ-[5,17-bis(diphenylphosphino)-25,26,
27,28-tetrapropoxycalix[4]arene]}palladium(II) tetrafluoroborate
16. A solution of AgBF4 (0.020 g, 0.10 mmol) in THF (1 cm3)
was added to a solution of [Pd(η3-C4H7)Cl]2 (0.020 g, 0.05
mmol) in CH2Cl2(3 cm3). Stirring was stopped after 5 min and
the solution was decanted to eliminate AgCl. The supernatant
was filtered through Celite and added to a solution of diphos-
phine 1 (0.100 g, 0.104 mmol) in CH2Cl2 (30 cm3). After 12 h the
solution was concentrated to ca. 5 cm3 and addition of pentane
afforded a white precipitate. Yield: 0.113 g, 90%. mp > 280 ЊC
(dec.). 1H NMR (CDCl3, 300 MHz, 298 K): δ 7.36–6.34 (30H,
aromatic H), 4.56 and 3.25 [d, AB spin system, 4H, ArCH2Ar,
3J(AB) = 14.1 Hz], 4.55 and 3.23 [d, AB spin system, 4H,
ArCH2Ar, 3J(AB) = 14.0 Hz], 4.12–4.05 (m, 4H, OCH2 of
OArP), 3.83 (t, 4H, OCH2 of OArBr, 3J = 5.7 Hz), 3.51 (broad s,
2H, CHsyn-allyl), 3.09–3.03 (broad m, 2H, CHanti-allyl), 2.06
(s, 3H, Me-allyl), 1.99–1.87 (m, 8H, OCH2CH2), 1.19 (t, 6H,
1
white precipitate. Yield: 0.172 g, 90%. mp > 280 ЊC. H NMR
(CDCl3): all signals are sharp: δ 7.26–6.98 (m, 24 H, PPh2 and
m-H of OArP), 6.88 (broad s, 4H, m-H of OAr), 4.56 and 3.26
3
[2d, AB spin system, 8H, ArCH2Ar, J(AB) = 13.7 Hz], 4.10
(t, 4H, OCH2 of OArP, 3J = 7.8 Hz), 3.82 (t, 4H, OCH2 of OAr,
3J = 6.3 Hz), 1.96–1.91 (m, 8H, OCH2CH2), 1.17 and 0.89 (2t,
3
12H, CH3, J = 7.3 Hz). 13C{1H} NMR (CDCl3): δ 159.10 and
157.31 (2s, arom. Cq–O), 136.49–123.94 (arom. C’s), 77.50 and
77.05 (2s, OCH2), 31.28 (s, ArCH2Ar), 23.63 and 22.84 (2s,
CH2CH3), 10.91 and 9.81 (2s, CH3). 31P{1H}NMR (CDCl3):
δ 10.4 [s with Pt satellites, PPh2, J(PPt) = 3651 Hz]. FAB mass
spectrum: m/z (%) 1226.3 (15) [Mϩ, expected isotopic profile)],
1191.3 (100) [(M Ϫ Cl)ϩ], 1155.3 (62) [(M Ϫ 2Cl)ϩ]. Found: C,
62.50; H, 5.37. Calc. for C64H66Cl2O4P2Pt (Mr = 1227.18): C,
62,64; H, 5.42%.
3
trans-P,PЈ-Dichloro{5,17-bis(diphenylphosphino)-25,26,27,28-
CH2CH3, J = 7.3 Hz), 0.88–0.85 (2 overlapping t, 6H, CH2-
CH3). Running the 1H NMR spectrum at 223 K on a 500 MHz
spectrum splits all signals, resulting in a C1-symmetrical species.
31P{1H} NMR (CDCl3, 298 K, 121 MHz): δ 23.11 (s, PPh2).
31P{1H}NMR (CD2Cl2, 223 K, 202 MHz): δ 24.4 and 24.0 [AB
spin system, J(AB) = 37 Hz]. FAB mass spectrum: m/z (%)
1121.3 (100) [(M Ϫ BF4)ϩ, expected isotopic profile], 1066.2
(20) [(M Ϫ Cl)ϩ, expected isotopic profile). Found: C, 67.71; H,
6.09. Calc. for C68H73BF4O4P2Pd (Mr = 1209.49): C, 67.53; H,
6.08%.
tetrapropoxycalix[4]arene}platinum(II) 14.
A
solution of
[PtCl2(PhCN)] (0.074 g, 0.16 mmol) in CH2Cl2 (150 cm3) was
added dropwise to a solution of 1 (0.150 mg, 0.16 mmol) in
CH2Cl2 (800 cm3) within 1 h. The resulting solution was stirred
overnight at room temperature. The solution was concentrated
to ca. 5 cm3 and addition of hexane afforded a yellow precip-
1
itate. Yield: 0.086 g, 45%. mp > 250 ЊC. H NMR (CDCl3):
all signals are sharp, in keeping with a monomeric structure:
δ 7.75–7.72 and 7.28–7.27 (2m, 20 H, PPh2), 6.85 and 6.70 (d
and t, AB2 spin system, 6H m-H and p-H of OAr, 3J = 7.5 Hz),
3
ϩ
5J(PH) = 10.5 Hz], 4.48
Dichloro(ꢀ6-p-cymene)[5-diphenylphosphino-11,17,23-
6.74 [virtual t, 4H, m-H of OArP,
and 3.14 [2d, AB spin system, 8H, ArCH2Ar, 3J(AB) = 13 Hz],
tribromo-25,26,27,28-tetrapropoxycalix[4]arene]ruthenium(II)
17. A solution of [RuCl2(p-cymene)]2 (0.034 g, 0.056 mmol) in
CH2Cl2 (5 cm3) was added dropwise to a solution of mono-
phosphine 5 (0.113 g, 0.112 mmol) in CH2Cl2 (50 cm3). After
stirring for 15 min the solution was concentrated to ca. 5 cm3.
Addition of hexane afforded 17 as an analytically pure orange
4.07 (t, 4H, OCH2 of OArP, 3J = 8.3 Hz), 3.77 (t, 4H, OCH2 of
3
OArBr, J = 6.9 Hz), 2.11–1.92 (2m, 8H, OCH2CH2), 1.14 and
0.91 (2t, 12H, CH3, 3J = 7.0 Hz). 13C{1H} NMR (CDCl3):
δ 157.02 and 156.33 (2s, arom. Cq–O), 133.35–122.00 (arom.
C’s), 77.42 and 76.42 (2s, OCH2), 30.80 (s, ArCH2Ar), 23.61
and 23.01 (2s, CH2CH3), 10.83 and 9.82 (2s, CH3). 31P{1H}
NMR (CDCl3): δ 20.6 [s with Pt satellites, PPh2, J(PPt) = 2584
Hz]. FAB mass spectrum: m/z (%) 1191.2 (38) [(M Ϫ Cl)ϩ,
expected istopic profile], 1170.3 (47) [(M Ϫ Cl ϩ O)ϩ, expected
isotopic profile], 1155.3 (100) [(M Ϫ 2Cl)ϩ, expected isotopic
profile] (the assignment of a monomeric structure is based on
the sharpness of the NMR signals). Found: C, 62.49; H, 5.63.
Calc. for C64H66Cl2O4P2Pt (Mr = 1227.18): C, 62.64; H, 5.42%.
1
powder. Yield: 0.125 g, 85%. mp 163 ЊC (dec.). H NMR (200
MHz, CDCl3): δ 7.56–7.26 (10H, PPh2), 7.12 [d, 2H, m-H of
3
OArP, J(PH) = 5 Hz], (s, 2H, m-H of OArBr), 7.10 and 7.00
4
[2d, AB spin system, 4H, m-H of OArBr, J(AB) = 2 Hz], 6.74
(s, 2H, m-H of OArBr), 5.13 and 4.10 [2d, AAЈBBЈ spin system,
8H, C6H4 of p-cymene, 3J(AB) = 3J(AЈBЈ) = 6 Hz], 4.47 and 3.21
[2d, AB spin system, 4H, ArCH2Ar, 2J(AB) = 13 Hz], 4.41 and
3.14 [2d, AB spin system, 4H, ArCH2Ar, 2J(AB) = 12 Hz], 4.06–
3.97 (m, 4H, OCH2 of OArBr), 3.80–3.72 [5H, OCH2 and
CH(CH3)2 of p-cymene], 2.12–1.86 (m, 8H, OCH2CH2), 1.25 [d,
6H, CH(CH3)2], 1.07, 1.00, and 0.96 (3 overlapping t, 3H : 6H :
3H, CH3), 1.03 (s, 3H, p-Me of p-cymene). As shown by a 2D
ROESY experiment, the ArMe protons correlate with the m-H
at 6.74 ppm. 31P{1H} NMR (CDCl3): δ 27.4 (s, PPh2). Found: C,
54.72; H, 5.18. Calc. for C62H68Br3Cl2O4PRuؒ1/2CH2Cl2 (Mr =
1319.89 ϩ 42.46): C, 55.10; H, 5.11%.
cis-P,PЈ-{[5,17-bis(diphenylphosphino)-25,26,27,28-tetraprop-
oxycalix[4]arene]norbornadiene}rhodium(I) tetrafluoroborate 15.
A solution of AgBF4 (0.031 g, 0.16 mmol) in THF (1 cm3) was
added to a solution of [{RhCl(norbornadiene)}2] (0.036 g, 0.08
mmol) in CH2Cl2 (10 cm3). Stirring was stopped after 5 min and
the solution was decanted to eliminate AgCl. The supernatant
was filtered through Celite and added to a solution of 1 (0.150
g, 0.16 mmol) in CH2Cl2 at Ϫ40 ЊC (30 cm3). After 1 h the
solution was concentrated to ca. 5 cm3 and addition of hexane
afforded an orange precipitate. Yield: 0.049 g, 25%. mp 227 ЊC
(dec.). 1H NMR (CDCl3): δ 7.22–6.76 (m, 24H, PPh2 and m-H
X-Ray crystallography
Crystal data for 12. Crystals suitable for X-ray diffraction
were obtained by slow evaporation of a chloroform solution:
C64H64Br2Cl2O4P2Ptؒ2CHCl3, M = 1623.74, triclinic, space
3
ϩ
of OArBr), 6.50 [virtual t, 4H, m-H of OArP,
5J(PH) = 10
Hz], 4.57 and 3.25 [2d, AB spin system, 8H, ArCH2Ar, 3J(AB) =
¯
13.9 Hz], 4.37 (broad s, 4H, ᎐CH of nbd), 4.08 (t, 4H, OCH of
group P1, colourless prisms, a = 14.9754(2), b = 15.6505(2),
᎐
2
OArP, 3J = 8.3 Hz), 3.91 (broad s, 2H, CH2 of nbd), 3.79 (t, 4H,
c = 16.3093(2) Å, α = 67.133(5), β = 69.265(5), γ = 83.969(5)Њ,
3
OCH2 of OArBr, J = 6.3 Hz), 1.94–1.87 (m, 8H, OCH2CH2),
U = 3291.59(7) Å3, Z = 2, µ = 0.377 mmϪ1, F(000) = 1616. Data
1.42 (broad s, 2H, CH of nbd), 1.14 and 0.84 (2t, 12H, CH3,
3J = 7.0 Hz). 13C{1H} NMR (CDCl3): δ 158.19 and 158.17 (2s,
arom. Cq–O), 136.99–122.31 (arom. C’s), 77.34 and 76.71 (2s,
OCH2), 52.70 (CH of nbd), 30.92 (s, ArCH2Ar), 29.72 (CH2 of
nbd), 23.61 and 22.76 (2s, CH2CH3), 10.87 and 9.70 (2s, CH3).
were collected on a Nonius KappaCCD diffractometer
(graphite Mo-Kα radiation, 0.71073 Å) at Ϫ100 ЊC. 21721
Reflections collected with 2.5 < θ < 27.50Њ, 12196 data with I >
3σ(I ). The structure was solved by direct methods and refined
anisotropically on F 2 using the OpenMoleN package.33
J. Chem. Soc., Dalton Trans., 2002, 1642–1650
1649

View Article Online
2 C. Wieser, C. B. Dieleman and D. Matt, Coord. Chem. Rev., 1997,
165, 93.
3 D. M. Roundhill, Prog. Inorg. Chem., 1995, 43, 533.
4 S. Steyer, D. Jeunesse, D. Armspach, D. Matt and J. M. Harrowfield,
in Calixarenes 2001, eds. Z. Asfari, V. Böhmer, J. M. Harrowfield
and J. Vicens, Kluwer Academic Publishers, Dordrecht, 2001,
pp. 513–535.
Hydrogen atoms were included using a riding model or rigid
methyl groups. Final results: R(F) = 0.031, wR(F) = 0.043,
goodness-of-fit = 1.012, 748 parameters, largest difference
peak = 1.181 e ÅϪ3
.
CCDC reference number 174550.
5 S. Shimizu, S. Shirakawa, Y. Sasaki and C. Hirai, Angew. Chem., Int.
Ed., 2000, 39, 1256.
6 C. Wieser-Jeunesse, D. Matt and A. De Cian, Angew. Chem., 1998,
37, 2861.
7 S. Blanchard, L. Le Clainche, M.-N. Rager, B. Chansou,
J.-P. Tuchagues, A. F. Duprat, Y. Le Mest and O. Reinaud, Angew.
Chem., Int. Ed., 1998, 37, 2732.
8 S. Blanchard, M.-N. Rager, A. F. Duprat and O. Reinaud, New J.
Chem., 1998, 22, 1143.
9 B. R. Cameron, S. J. Loeb and G. P. A. Yap, Inorg. Chem., 1997, 36,
5498.
10 E. Engeldinger, D. Armspach and D. Matt, Angew. Chem., Int. Ed.,
2001, 40, 2526.
11 M. Vézina, J. Gagnon, K. Villeneuve, M. Drouin and P. D. Harvey,
Organometallics, 2001, 20, 273.
12 M. Vézina, J. Gagnon, K. Villeneuve, M. Drouin and P. D. Harvey,
Chem. Commun., 2000, 1073.
13 C. Jaime, J. de Mendoza, P. Prados, P. M. Nieto and C. Sánchez,
J. Org. Chem., 1991, 56, 3372.
14 C. B. Dieleman, C. Marsol, D. Matt, N. Kyritsakas, A. Harriman
and J.-P. Kintzinger, J. Chem. Soc., Dalton Trans., 1999, 4139.
15 M. Lejeune, C. Jeunesse and D. Matt, Z. Krystallogr.–New Cryst.
Struct., 2002, 217, 51.
16 C. Wieser-Jeunesse, Thèse de Doctorat, University Louis Pasteur,
Strasbourg, 1998.
17 P. Tavs, Chem. Ber., 1970, 103, 2428.
Crystal data for 16. Crystals suitable for X-ray diffraction
were obtained by slow diffusion of hexane into a chloroform
solution of the complex: C68H73BF4O4P2PdؒCHCl3, M =
1328.87, tetragonal space group, P4/n, pale yellow, a =
34.292(5), b = 34.292(5), c = 11.204(5) Å, U = 13175(6) Å3,
Dc = 1.272, Z = 8, µ = 0.447 mmϪ1, F(000) = 5212. Data were
collected on a Nonius KappaCCD diffractometer (graphite
Mo-Kα radiation, 0.71073 Å) at Ϫ100 ЊC. 18836 Reflections
collected with 1.88 < θ < 30.03Њ, 9230 data with I > 2σ(I ). The
structure was solved by direct methods and refined anisotropic-
ally on F 2 using the SHELXL-97 procedure.34 Hydrogen atoms
were included using a riding model or rigid methyl groups. The
chloroform molecule is disordered over two positions. There is
also some disorder in one propyl group. Final results: R(F 2) =
0.073, wR(F 2) = 0.21, goodness-of-fit = 1.013, 734 parameters,
largest difference peak = 2.1 e ÅϪ3
.
CCDC reference number 174549.
Crystal data for 17. Crystals suitable for X-ray diffraction
were obtained by slow diffusion of hexane into a dichlorometh-
ane solution of the complex: C62H68Br3Cl2O4PRuؒ3CH2Cl2ؒ
¯
0.5hexane, M = 1617.80, triclinic, space group P1, orange–red
crystals, a = 11.7406(3), b = 15.2248(4), c = 21.8972(5) Å, α =
77.445(5), β = 88.005(5), γ = 73.474(5)Њ, U = 3661.2(2) Å3, Z = 2,
µ = 0.221 mmϪ1, F(000) = 1642. Data were collected on a
Nonius KappaCCD diffractometer (graphite Mo-Kα radiation,
0.71073 Å) at Ϫ100 ЊC. 21030 Reflections collected with 2.5 < θ
< 27.48Њ, 7201 data with I > 3σ(I ). The structure was solved by
direct methods and refined anisotropically on F 2 using the
OpenMoleN package.33 Hydrogen atoms were included using a
riding model or rigid methyl groups. One dichloromethane
molecule is disordered over two positions. Final results: R(F) =
0.060, wR(F) = 0.085, goodness-of-fit = 1.382, 732 parameters,
18 J. Gagnon, M. Vézina, M. Drouin and P. D. Harvey, Can. J. Chem.,
2001, 79, 1439.
19 F. Hamada, T. Fukugaki, K. Murai, G. W. Orr and J. Atwood,
J. Inclusion Phenom., 1991, 10, 57.
20 K. Takenaka, Y. Obora, L. Hong Jiang and Y. Tsuji, Bull. Chem.
Soc. Jpn., 2001, 74, 1709.
21 C. Dieleman, C. Loeber, D. Matt, A. De Cian and J. Fischer,
J. Chem. Soc., Dalton Trans., 1995, 3097.
22 H. Günther, NMR-Spektroskopie, 3rd edn., Thieme, Stuttgart, 1992,
pp. 309–310.
23 C. Jeunesse, C. Dieleman, S. Steyer and D. Matt, J. Chem. Soc.,
Dalton Trans., 2001, 881.
24 J. Suffert, J. Org. Chem., 1989, 54, 509.
largest difference peak = 1.059 e ÅϪ3
.
25 M. Larsen and M. Jørgensen, J. Org. Chem., 1996, 61, 6651.
26 R. Uson, A. Laguna and M. Laguna, Inorg. Synth., 1989, 26, 85.
27 A. C. Cope and E. C. Friedrich, J. Am. Chem. Soc., 1968, 90, 909.
28 M. A. Bennett, T.-N. Huang, T. W. Matheson and A. K. Smith, in
Inorganic Synthesis, vol. 21, ed. J. P. Fackler, Jr., John Wiley & Sons,
New York, 1982, p. 75.
CCDC reference number 174551.
See http://www.rsc.org/suppdata/dt/b1/b110884k/ for crystal-
lographic data in CIF or other electronic format.
29 D. Drew and J. R. Doyle, in Inorganic Synthesis, vol. 28, ed.
R. J. Angelici, Wiley, New York, 1990, pp. 350–352.
30 F. R. Hartley, The Chemistry of Platinum and Palladium, Wiley,
New York, 1973.
31 E. W. Abel, M. A. Bennett and G. Wilkinson, J. Chem. Soc., 1959,
3178.
Acknowledgements
We are grateful to Johnson Mathey for a generous loan of
precious metals. We thank the University Louis Pasteur for
financial support.
32 W. D. Dent, R. Long and A. J. Wilkinson, J. Chem. Soc., 1964, 1585.
33 OpenMoleN, Interactive Structure Solution, Nonius B.V., Delft,
1997.
34 G. M. Sheldrick, SHELX-97, Program for the refinement of crystal
structures, University of Göttingen, Germany, 1997.
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J. Chem. Soc., Dalton Trans., 2002, 1642–1650