Five-coordinate Pd(ii) orthometallated triarylphosphite complexes

Article abstract of DOI:10.1039/b613524b

The reaction of the orthopalladated triarylphosphite complexes [{Pd(-Cl){κ²-P,C-P(OC₆H₂-2,4-R ₂)(OC₆H₃-2,4-R₂)}₂] (R = H, ^tBu) with bis(2-diphenylphosphinoethyl)phenylphosphine leads to a five-coordinate palladium(ii) (R = H) and a mixture containing four-and five-coordinate species (R = ^tBu). The crystal structure of the five-coordinate species [Pd{κ²-P,C-(P(OC₆H ₄)(OC₆H₅)₂}{bis(2- diphenylphosphinoethyl)phenylphosphine}][SbF₆] is presented. This complex reacts with hydrogen peroxide or [AuCl(tht)] to give four-coordinate complexes in which the displaced phosphine residue is either oxidised or coordinated to gold chloride; this demonstrates that the five-coordinate complexes are labile in solution. By contrast, the reactions of the dimeric precursors with 1,1,1-tris(diphenylphosphinomethyl)ethane give four-coordinate complexes in the solid state, although evidence is presented that the smaller phosphite-containing system is five-coordinate at room temperature or higher in solution. The Royal Society of Chemistry.

Full text of DOI:10.1039/b613524b

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www.rsc.org/dalton | Dalton Transactions
Five-coordinate Pd(II) orthometallated triarylphosphite complexes
Robin B. Bedford,*a Michael Betham,a Craig P. Butts,a Simon J. Coles,b Marica Cutajar,c Thomas Gelbrich,b
Michael B. Hursthouse,b P. Noelle Scullyd and Stephen Wimperisc
Received 18th September 2006, Accepted 14th November 2006
First published as an Advance Article on the web 12th December 2006
DOI: 10.1039/b613524b
The reaction of the orthopalladated triarylphosphite complexes [{Pd(l-Cl){j2-P,C-P(OC6H2-2,4-R2)-
(OC6H3-2,4-R2)}2] (R = H, tBu) with bis(2-diphenylphosphinoethyl)phenylphosphine leads to a
five-coordinate palladium(II) (R = H) and a mixture containing four-and five-coordinate species
t
(R = Bu). The crystal structure of the five-coordinate species [Pd{j2-P,C-(P(OC6H4)(OC6H5)2}-
{bis(2-diphenylphosphinoethyl)phenylphosphine}][SbF6] is presented. This complex reacts with
hydrogen peroxide or [AuCl(tht)] to give four-coordinate complexes in which the displaced phosphine
residue is either oxidised or coordinated to gold chloride; this demonstrates that the five-coordinate
complexes are labile in solution. By contrast, the reactions of the dimeric precursors with
1,1,1-tris(diphenylphosphinomethyl)ethane give four-coordinate complexes in the solid state, although
evidence is presented that the smaller phosphite-containing system is five-coordinate at room
temperature or higher in solution.
study as it has been shown to form a range of five-coordinate com-
Introduction
plexes with Pd(II).4 In contrast, to the best of our knowledge, 1,1,1-
The organometallic chemistry of palladium(II) is dominated by
tris(diphenylphosphinomethyl)-ethane, 4, has not been shown to
the formation of stable, square-planar four-coordinate complexes;
support five-coordinate Pd(II) geometries, therefore we thought it
would make an interesting comparison. The results of this study
Whilst there are plenty of examples of five-coordinate Pd(II)
are presented below.
higher coordination number complexes are much less prevalent.1
species, they often show unusual structural features. These are
particularly apparent in the structures of five-coordinate pallada-
cyclic complexes. For instance Vila and co-workers demonstrated
Results and discussion
that triphos adducts of N-based palladacycles, complex 1, tend
to show increased Pd–N bond lengths compared with four-
coordinate palladacycles,2 while Albinati et al. showed that the
cyclopentadienyl ligand in complex 2 can best be described as
having a localised diene structure.3
Bis(2-diphenylphosphinoethyl)phenylphosphine complexes
The orthometallated triphenylphosphite complex 5a reacts
cleanly with the tridentate phosphine ligand bis(2-diphenyl-
phosphinoethyl)phenylphosphine 3 and silver hexafluoroanti-
monate in CH2Cl2 to give the cationic, five-coordinate complex
[Pd{j2 - P,C - P(OC6H4)(OPh)2}{j3-PhP(CH2CH2PPh2)2}][SbF6],
6a in 69% yield (Scheme 1).
The 31P NMR spectrum of complex 6a is particularly informa-
tive. It shows a typical AB2X pattern with the ‘A’ signal at d 142.8,
the ‘X’ signal at 82.2 and the ‘B’ signal at 39.7 ppm (JAB = 265 Hz,
JAX = 35 Hz, JBX = 25 Hz) with a 5 Hz 2nd order splitting. The
low-field peak corresponds to the metallated triphenylphosphite
ligand and has shifted approximately 17 ppm downfield compared
with the signals for the trans and cis isomers of the starting
complex 5a. This data is consistent with the triphenylphosphite
ligand still being orthometallated; for comparison the cationic,
four-coordinate dppe-containing complexes 7a and 7b show peaks
at 135.8 and 140.6 ppm respectively corresponding to the or-
thometallated phosphite donor,3,5 whilst the non-orthometallated
complex [PdCl2{P(OPh)3}2] shows a singlet at 83 ppm.3
To the best of our knowledge, complex 2 represents the only
five-coordinate phosphite-based palladacycle. We were interested
to see whether other phosphite-based palladacycles will tolerate
five-coordinate geometries supported by phosphine donors and
therefore decided to investigate the reactions of palladacyclic
precursors with tridentate phosphine ligands. The ligand bis(2-
diphenylphosphinoethyl)phenylphosphine, 3, was chosen for this
aSchool of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8
1TS, UK. E-mail: r.bedford@bristol.ac.uk
bEPSRC National Crystallography Service, Department of Chemistry,
University of Southampton, Highfield Road, Southampton, SO17 1BJ, UK
cDepartment of Chemistry and WestCHEM, University of Glasgow, Glasgow,
G12 8QQ, UK
dSchool of Chemistry, Trinity College Dublin, Dublin 2, Ireland
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Fig. 1 31P MAS NMR spectrum of complex 6a. Spinning sidebands are
marked with *.
Scheme 1 Conditions: (i) PhP{(CH2)2PPh2}2, CH2Cl2, r.t., 1 h, then
Ag[SbF6], r.t. 1 h. (ii) H2O2 (30%, aq), CH2Cl2, r.t. 18 h. (iii) [AuCl(tht)],
CH2Cl2, r.t., 1 h.
The coupling of the phosphite peak of 6a to the two equivalent
diphenylphosphino P atoms of 265 Hz is too large for cis
coupling and too small for trans coupling, consistent with these
three P-donors occupying the equatorial positions of a trigonal
bipyramidal structure. By way of comparison the 2JPP cis couplings
to the phosphites in the square planar complexes 7a and 7b are
30 and 33 Hz respectively, while the trans couplings are 515 and
502 Hz.3,5 The proton NMR of complex 6a shows a low-field
apparent triplet at 6.06 ppm with a coupling of ∼8 Hz and another
at 6.31 ppm (∼8 Hz coupling) both integrating to 1 proton. A
COSY spectrum reveals they are mutually coupled. The low-field
shifts and the mutual couplings suggest these peaks correspond to
the orthometallated ring proton adjacent to the orthometallated
carbon and its neighbour respectively.
The solid-state 31P MAS NMR spectrum of 6a was recorded and
is shown in Fig. 1. The lines are too broad to identify cis couplings,
but larger couplings are evident. It is obvious that the solid-state
spectrum is somewhat different from that recorded in solution,
presumably as a result of lower symmetry. The apparent triplet at
d 147.9 ppm corresponds to the orthometallated phosphite ligand,
while the peak at 71.3 ppm corresponds to the phenylphosphino
residue. The diphenylphosphino residues are not equivalent as
they are in solution, but rather are seen as two multiplets at 52.1
and 21.0 ppm.
Fig. 2 X-Ray structure of complex 6a with solvent, counter ion and
hydrogen atoms omitted for clarity. Thermal ellipsoids are shown at 30%
probability. Selected bond lengths and angles: Pd1–C1, 2.073(3); Pd1–P1,
2.2597(8); Pd1–P2, 2.4243(8); Pd1–P3, 2.3156(8); Pd1–P4, 2.3876(8)
˚
A; C1–Pd1–P1, 80.12(8); C1–Pd1–P2, 93.77(8); C1–Pd1–P4, 95.19(8);
C1–Pd1–P3, 178.18(8); P1–Pd1–P2, 119.14(3); P1–Pd1–P4, 127.24(3);
P2–Pd1–P4, 113.59(3); P1–Pd1–P3, 101.70(3); P2–Pd1–P3, 85.21(3);
P4–Pd1–P3, 83.84(3)◦.
approximately trigonal bipyramidal structure about the palladium
with the phenylphosphino residue trans to the orthometallated
aryl group. The two diphenylphosphino groups are obviously not
equivalent, both in terms of orientation of the phenyl groups
and the ethylene bridges and the angles formed at palladium
with respect to P1. The P1–Pd1–P4 angle is considerably larger
than the P1–Pd1–P2 angle. This inequivalence explains the two
distinct PPh2 environments observed in the solid-state 31P MAS
NMR spectrum. While there is little change in the Pd–C bond
length compared with neutral four-coordinate orthopalladated
triarylphosphite complexes (although the value lies at the upper
end of the range),5,6 the palladium–phosphite bond length is
significantly longer. This is in contrast with the five-coordinate
palladacyclic complex 2 which shows no elongation of the Pd–P or
Pd–Caryl bond lengths compared with other arylphosphite-based
The inequivalence of the two diphenylphosphino residues in the
solid state was confirmed by the results of a single crystal X-ray
analysis of complex 6a (Fig. 2). As can be seen the cation adopts an
460 | Dalton Trans., 2007, 459–466
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palladacycles, but rather the structural perturbation on forcing
five-coordinate geometry is manifest in the bonding to the
Cp ligand.3 In this regard complex 6a more closely resembles
complexes of the type 1 which show an elongation of the Pd–N
bond in the palladacyclic ring.2
exhibit a resolved 2nd order AB2X splitting as in 6a, but appears as
a doublet of triplets at 140.9 ppm with a large coupling of 278 Hz
to the equivalent PPh2 residues and small coupling of 29 Hz to the
PPh residue. These data are broadly similar to those for complex
6a. The chemical shifts for both the phenylphosphino (75.3) and
the diphenylphosphino (29.9) residues are shifted 5.8 and 8.9 ppm
upfield respectively. This may be due to slight differences in the
structure as a result of unfavourable steric interactions between
the tert-butyl group in the 5-position of the orthometalled ring
and the diphenylphosphino residues. The mutual cis coupling
between the PPh and PPh2 donors is 24 Hz. The minor species
is assigned as the four-coordinate complex 10 in which one of
Complex 6a shows no sign of oxidation in aerobic solution after
1 week, however it reacts with aqueous hydrogen peroxide to give
oxidation of one diphenylphosphino residue per molecule. The 31
P
NMR spectrum recorded after 1 h shows a mixture of starting
material and peaks assigned to the two isomers of the complex 8
(Scheme 1), which are obtained in an approximately 3 : 2 ratio.
When the reaction is left overnight, all of the starting material
is oxidised, but there are also a number of new, broad peaks
presumably associated with over-oxidised products. This reaction
indicates that phosphine decoordination occurs for complex 6a,
implying that it is in equilibrium with a four-coordinate complex
in solution. Further evidence for this decoordination process is
provided by the reaction of complex 6a with [AuCl(tht)] which
generates the two isomers of complex 9 (Scheme 1). With the
exception of the peaks associated with the PPh2 coordinated to
the AuCl, the 31P NMR spectrum of the mixture of isomers is
broadly similar to that for the two isomers of the oxides 8.
In contrast with the clean reaction obtained with complex 5a,
when the bulky analogue 5b is reacted with 3 (Scheme 2), a
mixture of two products is obtained, as determined by 31P NMR
spectroscopy. The major product (∼70%) is assigned as the five-
coordinate complex 6b, by comparison of the 31P NMR data with
that of complex 6a. The phosphite donor of complex 6b does not
the diphenylphosphino residues remains un-coordinated. The 31
P
NMR spectrum shows a doublet of multiplets for the phosphite
donor at 142.9 ppm with a trans coupling of 485 Hz. This is
coupled to a doublet of doublets at 54.7 ppm which is assigned as
a diphenylphosphino residue7 which also shows a cis coupling of
30 Hz to the phenylphosphino phosphorus. The phenylphosphino
residue is seen as a broad multiplet at 47.1 ppm, while the
non-coordinated diphenylphosphino residue is seen as a broad
multiplet at −17.5 ppm.
The reaction of the mixture of the five-coordinate 6b and the
four-coordinate 10 with [AuCl(tht)] gives clean conversion to the
two possible isomers of complex 11 in an approximately 1 : 1 ratio.
This implies that the five-coordinate complex 6b is in equilibrium
with the four-coordinate complex 10 in solution.
1,1,1-Tris(diphenylphosphinomethyl)ethane complexes
The reaction of the bulky orthometallated phosphite com-
plex 5b with the symmetrical tridentate phosphine 1,1,1-tris-
(diphenylphosphinomethyl)ethane, 4, and ammonium hexafluoro-
phosphate in CH2Cl2, does not give a five-coordinate complex, but
rather yields the four-coordinate species, [Pd{j2-P, C-P(OC6H2-
2,4-tBu2)(OC6H3-2,4-tBu2)2}{j2-MeC(CH2CH2PPh2)3}][PF6], 12a
(Scheme 3).
The 31P NMR of 12a shows a doublet of doublets at 137.5 ppm
corresponding with the phosphite, with a large trans coupling
(500 Hz) and a small cis coupling (32 Hz) to two of the PPh2
residues. These phosphines are observed as doublets of doublets
at 18.3 (P trans to phosphite) and 2.5 ppm (P cis to phosphite) and
show a mutual cis coupling of 60 Hz. The third phosphine residue
is observed as a singlet at −28.1 ppm, very close to that of the free
phosphine (−27 ppm). The heptet for the hexafluorophosphate
anion is seen at −143.1 ppm. On standing in air in CDCl3
solution, the complex 12a undergoes slow (days) partial oxidation
to produce the complex 13a in which the free phosphine has been
oxidised. The complex 13a can be synthesised cleanly by treating
12a with hydrogen peroxide solution. The structure of 13a was
determined by single crystal X-ray analysis and the cation is shown
in Fig. 3, along with selected data.
The reaction of ligand 4 with the less sterically hindered
triphenylphosphite complex 5a and ammonium hexafluorophos-
phate gives a new complex, 14, (Scheme 3) which, unusually
for palladium(II) complexes of this ligand,8 appears to be five-
coordinate at room temperature in solution. The 31P NMR
spectrum of 14 recorded at 20 ◦C in either CDCl3, or CD2Cl2
shows a very broad peak at about d −5 ppm and a non-first
order pseudo-quartet at about 131 ppm. The spectrum recorded
Scheme 2 Conditions: (i) PhP{(CH2)2PPh2}, CH2Cl2, r.t., 1 h, then
[NH4][PF6], r.t. 1 h. (ii) [AuCl(tht)], CH2Cl2, r.t., 1 h.
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Fig. 4 31P MAS NMR spectrum of complex 12b. Spinning sidebands
marked with *.
◦
in accord with the solution data recorded at −90 C, indicating
that the four-coordinated complex 12b is the sole P-containing
species in the solid state. This was confirmed by single crystal
X-ray analysis; the cation of 12b is shown in Fig. 5, along with
selected data.
Scheme 3 Conditions: (i): Me(CH2PPh2)3, CH2Cl2, r.t., 1 h, then
[NH4][PF6], r.t. 1 h. (ii) H2O2 (30%, aq), CH2Cl2, r.t.
Fig. 5 X-Ray structure of complex 12b with solvent, counter ion and
hydrogen atoms omitted for clarity. Thermal ellipsoids are shown at 30%
probability. Selected bond lengths and angles: Pd1–C1, 2.100(3); Pd1–P1,
Fig.
3 X-Ray structure of the cation of complex 13a with sol-
vent, counter ion and hydrogen atoms omitted for clarity. Thermal
ellipsoids are shown at 30% probability. Selected bond lengths and
angles: Pd1–C41, 2.118(4); Pd1–P1, 2.3772(12); Pd1–P2, 2.3233(12);
Pd1–P4, 2.2594(11) A; C41–Pd1–P1, 175.55(11); C41–Pd1–P2, 92.79(11);
C41–Pd1–P4, 78.88(11); P1–Pd1–P2, 90.59(4); P1–Pd1–P4, 97.91(4);
P2–Pd1–P4, 170.93(5)◦.
˚
2.2253(10); Pd1–P2, 2.3443(10); Pd1–P3, 2.3454(10) A; C1–Pd1–P1,
79.41(8); C1–Pd1–P2, 96.82(8); C1–Pd1–P3, 166.97(8); P1–Pd1–P2,
171.78(3); P1–Pd1–P3, 92.72(4); P2–Pd1–P3, 92.26(4)◦.
˚
Complex 14 is readily oxidised with hydrogen peroxide to give
complex 13b; the 31P NMR data are very similar to those obtained
for complex 13a.
In summary, the outcome of the reactions of orthopalla-
dated triarylphosphite complexes with bis(2-diphenylphosphino-
ethyl)phenylphosphine depends on the size of the phenolate
residue on the phosphite, with a smaller orthometallated ligand
more readily supporting the formation of a five-coordinate
complex. Even when a five-coordinate complex is obtained as
the sole product (6a) its propensity to produce four-coordinate
in chloroform at 60 ◦C shows a quartet for the phosphite donor at
130.5 ppm with a coupling of 160 Hz and a broad doublet for all
three phosphine donors at d − 4.2 ppm (coupling 160 Hz). This
implies that at elevated temperatures complex 14 is five-coordinate
and fluxional, as shown in Scheme 3. However, on cooling the
CD2Cl2 solution to −90 ◦C the spectrum obtained is consistent
with the four-coordinate complex 12b and is very similar to that
recorded for complex 12a. The 31P MAS NMR spectrum recorded
at 18 kHz spinning speed is shown in Fig. 4. This spectrum is
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species is illustrated by (a) its reaction with hydrogen peroxide
or [AuCl(tht)], and (b) by structural data that shows a sub-
stantial increase in Pd–Pphosphite bond length compared with four-
coordinate analogues. The reaction of complex 5a with 1,1,1-
tris(diphenylphosphinomethyl)ethane furnishes a rare example
of a five-coordinate Pd(II) complex with this tridentate ligand,
albeit only in the solution state at room temperature or higher.
We are currently investigating the synthesis of five-coordinate
orthopalladated triarylphosphite complexes which contain 1,4,7-
trithiacyclononane. The complexes show intriguing hydrogen-
bonding properties and the results from this study will be presented
in the near future.
CH), 131.2 (s, Ar CH), 131.3 (d, JPC = 4 Hz, Ar C), 131.4 (s, Ar
CH’), 131.8 (s, Ar CH), 131.9 (s, Ar CH), 132.0 (s, Ar CH), 132.7
(s, Ar CH), 133.3 (s, Ar CH), 133.4 (s, Ar CH), 133.8 (dt, JPC
2 and 6 Hz, Ar C), 134.4 (d, JPC = 4 Hz, Ar C), 134.8 (t, JPC
=
=
8 Hz, Ar C), 141.2 (d, JPC = 5 Hz, Ar C), 152.5 (d, JPC = 11 Hz,
Ar C).
Oxidation of complex 6a with hydrogen peroxide. Complex
6a (0.100 g, 0.083 mmol) was dissolved in CH2Cl2 (10 mL) and
stirred vigorously with H2O2 (30% w/w solution in water, 10 mL)
at room temperature for 18 h. The solution was then diluted
with water (50 mL) and the product extracted with CH2Cl2 (2 ×
50 mL). The combined organic extracts were dried (MgSO4) and
the solvent removed under reduced pressure to give an off-white
solid. The long reaction time was required to ensure complete
consumption of the starting material but led to some over-
Experimental
General considerations
1
oxidation, as exemplified by a complex H NMR spectrum and
the presence of several minor peaks in the 31P NMR spectrum. 8a
All reactions and manipulations were carried out under nitrogen
using either a glove-box or standard Schlenk techniques. Solvents
were dried and freshly distilled prior to use. CDCl3 was dried
with CaH2, then vacuum transferred and stored under nitrogen.
All other chemicals were used as received unless otherwise stated.
The palladium complexes 5a and 5b were prepared by literature
methods.3,5 1H, 13C and 31P NMR spectra were recorded on a
Bruker ACF-300 spectrometer (300, 75 and 121.5 MHz respec-
tively) at ambient temperature unless otherwise stated. Variable
1
(Major, ∼60%): 31P{ H} NMR (CDCl3, 121.5 MHz): d 136.1 (dd,
JPP = 34 and 511 Hz, o-metallated phosphite), 59.6 (ddd, JPP
=
29, 52 and 511 Hz, trans-PPh), 47.3 (dd, JPP = 29 and 34 Hz,
cis-PPh2), 34.5 (d, JPP = 52 Hz, P(O)Ph2). 8b (Minor, ∼ 40%):
1
31P{ H} NMR (CDCl3, 121.5 MHz): d 136.1 (dd, JPP = 35 and
515 Hz, o-metallated phosphite), 59.6 (dd, JPP = 29 and 515 Hz,
trans-PPh2), 45.1 (ddd, JPP = 29 and 39 Hz, cis-PPh), 34.0 (d, JPP
=
39 Hz, P(O)Ph2). 1H NMR spectrum broad and uninformative.
1
temperature H and 31P NMR experiments were undertaken on
Reaction of complex 6a with [AuCl(tht)]. [Pd{j2-P,C-(P(OC6-
H4)(OC6H5)2}{bis(2-diphenylphosphinoethyl)phenyl-phosphine}]-
[SbF6] (0.033 g, 0.028 mmol) and (tht)AuCl (0.009 g, 0.028 mmol)
were dissolved in CH2Cl2 (15 mL) and stirred for 1 h at room
temperature. The solvent was removed in vacuo and the crude
product was repeatedly precipitated from CH2Cl2–hexane to
give an off-white powder. Yield: 0.030 g (74%). Anal. Calcd for
C52H47AuClF6O3P4Pd: C, 44.0; H, 3.3%. Found: C, 45.1; H, 3.6%.
a Bruker Avance DRX-400 spectrometer (400 and 162 MHz
respectively). Solid-state 31P MAS NMR spectra were recorded
using a spinning speed of 18 kHz on a Bruker Avance-400
spectrometer (162 MHz) at ambient temperature.
Preparation of [Pd{j2-P,C-(P(OC6H4)(OC6H5)2}{bis(2-di-
phenylphosphinoethyl)phenylphosphine}][SbF6],
6a. Complex
5a (0.168 g, 0.187 mmol) and ligand 3 (0.20 g, 0.374 mmol)
were dissolved in CH2Cl2 (15 mL), then allowed to stir at room
temperature for 1 h. Ag[SbF6] (0.11 g, 0.32 mmol) was then added
as a solution in CH2Cl2 (5 mL), the solution was stirred at room
temperature for 1 h and then filtered through Celite. The solvent
was removed under reduced pressure to give a bright yellow solid.
The crude product was then recrystallized from CH2Cl2–hexane
to give 6a as yellow crystals. Yield: 0.31 g (69%). Crystals of
6a suitable for X-ray analysis were grown from CH2Cl2–hexane.
Anal. Calcd for C52H47F6O3P4PdSb: C, 52.7; H, 4.0%. Found: C,
52.2; H, 4.1%. HRMS (FI) [M]+ Calcd for C52H47F6O3P4PdSb:
1184.0453 found: 1184.0470. 1H NMR (CDCl3, 300 MHz): d
2.36–2.84 (m, 8H, 4 × PCH2), 6.06 (t, 1H, 3JHH = 8 Hz, Ar–H),
6.31 (t, 1H, 3JHH = 8 Hz, Ar–H), 6.35 (m, 3H, Ar–H), 6.85–6.95
(m, 10H, Ar–H), 7.05–7.11 (m, 10H, Ar–H), 7.17–7.28 (m, 6H,
Ar–H), 7.35 (t, 2H, 3JHH = 7 Hz, Ar–H), 7.45 (m, 4H, Ar–H), 7.62
1
9a (Major, ∼65%): H NMR (CDCl3, 300 MHz): d 1.90–2.33
3
(m, 4H, PCH2), 2.35–2.85 (m, 4H, PCH2), 6.50 (t, 1H, JHH
=
3
8 Hz, Ar–H), 6.69 (br d, 1H, JHH = 7 Hz, Ar–H), 6.85 (m, 2H,
Ar–H), 6.99–7.63 (m, 35H, Ar–H). 31P{ H} NMR (CDCl3, 121.5
1
MHz): d 137.3 (dd, JPP = 38 and 514 Hz, o-metallated phosphite),
55.8 (dd, JPP = 29 and 514 Hz, trans-PPh2), 45.3 (ddd, JPP
=
29, 38 and 41 Hz, cis-PPh), 35.0 (d, JPP = 41 Hz, P(O)Ph2). 9b
1
(Minor, ∼35%): H NMR (CDCl3, 300 MHz): d 1.90–2.33 (m,
4H, PCH2), 2.35–2.85 (m, 4H, PCH2), 6.58 (m, 1H, Ar–H), 6.66
(m, 1H, Ar–H), 6.90 (m, 1H, Ar–H), 6.99–7.63 (m, 35H, Ar–H).
31P{ H} NMR (CDCl3, 121.5 MHz): d 136.1 (dd, JPP = 34 and
1
512 Hz, o-metallated phosphite), 59.6 (ddd, JPP = 28, 59 and
512 Hz, trans-PPh), 45.1 (dd, JPP = 28 and 34 Hz, cis-PPh2), 34.0
(d, JPP = 59 Hz, P(O)Ph2). 13C{ H} NMR (CDCl3, 75 MHz): (9a
1
and 9b) d 29.9, 30.0, 30.5, 30.7, 31.2, 31.3, 119.0 (d, JPC = 8 Hz,
Ar C), 119.4 (d, JPC = 8 Hz, Ar C), 125.3, 125.4, 125.5, 128.5,
128.7, 128.9, 129.0, 129.2, 129.3, 129.4, 129.6, 130.4, 130.6, 131.2,
131.3, 131.4, 131.6, 131.7, 132.0, 132.3, 132.4, 132.5, 132.6, 132.9,
1
(m, 2H, Ar–H). 31P{ H} NMR (CDCl3, 121.5 MHz): d 142.8 (dt,
AB2X, JAB = 265 Hz, JAX = 35 Hz and JBX 25 Hz, o-metallated
phosphite), 82.2 (dt, JPP = 25 and 35 Hz, PPh), 39.7 (dd, JPP
=
1
25 and 265 Hz, PPh2). 31P{ H} MAS NMR (162 MHz, spinning
at 18 kHz): d 147.9 (apparent t, JPP = ∼280 Hz, o-metallated
phosphite), 71.3 (s, PPh), 52.1 (dd, JPP = ∼130 and ∼280 Hz,
133.0, 134.4, 134.6, 134.8, 134.9, 141.0, 141.3, 149.9 (d, JPC
9 Hz, Ar C), 150.0 (d, JPC = 9 Hz, Ar C).
=
1
PPh2), 21.9 (dd, JPP = ∼130 and ∼280 Hz, PPh2). 13C{ H} NMR
Reaction of complex 5b with bis(2-di-phenylphosphino-
ethyl)phenylphosphine. Complex 5b (0.252 g, 0.16 mmol)
and bis(2-diphenylphosphinoethyl)phenyl-phosphine (0.171 g,
0.32 mmol) were dissolved in CH2Cl2 (15 mL), and the resultant
(CD2Cl2, 75 MHz): d 29.3 (PCH2), 29.7 (PCH2), 31.2 (PCH2),
31.3 (PCH2), 115.9 (d, JPC = 16 Hz, Ar C), 122.7 (d, JPC = 4 Hz,
Ar C), 124.9 (d, JPC = 9 Hz, Ar C), 127.5 (s, Ar CH), 129.1 (s, Ar
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solution stirred at room temperature for 1 h. [NH4][PF6] (0.052 g,
0.32 mmol) was then added, and the mixture was stirred at room
temperature for 1 h and then filtered through Celite. The solvent
was removed under reduced pressure to give a bright yellow
solid. The crude product was then recrystallized from CH2Cl2–
hexane to give yellow crystals. Yield: 0.27 g (60%). Anal. Calcd
for C76H95F6O3P5Pd: C, 63.8; H, 6.7%. Found: C, 64.5; H, 7.0%.
PPh), 42.0 (dd, JPP = 30 and 32 Hz, cis-PPh2), 33.3 (d, JPP = 53 Hz,
1
Ph2PAuCl), −143.0 (heptet, JFP = 710 Hz, PF6). 13C{ H} NMR
(CDCl3, 75 MHz): (11a and 11b) d 27.3, 27.8, 28.8, 30.0, 30.4,
30.6, 31.6, 32.1, 33.1, 33.6, 33.8, 36.6, 36.9, 37.3, 37.5, 37.6, 121.1,
121.4, 125.2, 125.3, 125.4, 126.1, 127.3, 131.3, 131.4, 131.5, 131.7,
131.8, 131.9, 132.0, 132.8, 133.1, 133.3, 133.6, 134.3, 134.5, 134.6,
134.7, 134.9, 136.0, 138.1, 139.1, 140.6, 149.0, 150.2, 150.4, 150.9,
151.0.
1
6b (Major, ∼70%): H NMR (CDCl3, 300 MHz): d 0.66 (s, 9H,
C(CH3)3 o-metallated ring), 0.74 (s, 9H, C(CH3)3 o-metallated
ring), 1.10 (s, 18H, C(CH3)3), 1.19 (s, 18H, C(CH3)3), 2.35–2.78
Preparation of [Pd{j2-P,C-(P(OC6H2-2,4-tBu2)(OC6H3-2,4-
tBu2)2}{j2-1,1,1-tris(diphenylphosphinomethyl)ethane}][PF6], 12a.
[{Pd(l-Cl){j2 -P,C-(P(OC6H2 -2,4-tBu2 )(OC6H3 -2,4-tBu2 )2 }}2]
(0.252 g, 0.16 mmol) and 1,1,1-tris(diphenyl-phosphinomethyl)-
ethane (0.20 g, 0.32 mmol) were dissolved in CH2Cl2 (10 mL), then
allowed to stir at room temperature for 1 h. [NH4][PF6] (0.052 g,
0.32 mmol) was then added, causing immediate precipitation
of NH4Cl. The solution was stirred at room temperature for
1 h and then filtered through Celite. The solvent was removed
under reduced pressure to give an off-white solid. The crude
product was then recrystallized from CH2Cl2–hexane to give
white crystals after drying in vacuo. Yield: 0.30 g (63%). Anal.
Calcd for C83H101F6O3P5Pd: C, 65.5; H, 6.7%. Found: C, 66.1;
3
(m, 8H, 4 × PCH2), 6.12 (dd, 2H, JHH = 3 and 9 Hz, Ar–H),
6.76 (br m, 2H, Ar–H), 6.86 (t, 2H, 3JHH = 9 Hz, Ar–H), 6.95 (dd,
2H, 3JHH = 3 and 9 Hz, Ar–H), 7.01–7.49 (m, 24H, Ar–H), 7.91
3
1
(dd, 1H, JHH = 9 and 11 Hz, Ar–H o-metallated ring). 31P{ H}
NMR (CDCl3, 121.5 MHz): d 140.9 (dt, JPP = 29 and 278 Hz,
o-metallated phosphite), 75.3 (dt, JPP = 24 and 29 Hz, PPh), 29.8
(dd, JPP = 24 and 278 Hz, PPh2), −143.0 (heptet, JFP = 710 Hz,
PF6). 10 (Minor, ∼30%): 1H NMR (CDCl3, 300 MHz): d 0.70 (s,
9H, C(CH3)3 o-metallated ring), 0.75 (s, 9H, C(CH3)3 o-metallated
ring), 1.10 (s, 18H, C(CH3)3), 1.19 (s, 18H, C(CH3)3), 2.35–2.78
3
(m, 8H, 4 × PCH2), 6.12 (dd, 2H, JHH = 3 and 9 Hz, Ar–H),
6.78 (br m, 2H, Ar–H), 6.88 (t, 2H, 3JHH = 9 Hz, Ar–H), 6.95 (dd,
2H, 3JHH = 3 and 9 Hz, Ar–H), 7.01–7.49 (m, 24H, Ar–H), 7.91
1
H, 6.8%. H NMR (CDCl3, 300 MHz): d 0.44 (br s, 3H, CH3),
0.53 (s, 9H, C(CH3)3 o-metallated ring), 0.83 (s, 9H, C(CH3)3
o-metallated ring), 1.10 (s, 18H, C(CH3)3), 1.27 (s, 18H, C(CH3)3),
1.88–2.76 (m, 6H, PCH2), 6.84 (m, 1H, Ar–H), 6.92–7.01 (m, 4H,
3
1
(dd, 1H, JHH = 9 and 11 Hz, Ar–H o-metallated ring). 31P{ H}
NMR (CDCl3, 121.5 MHz): d 142.9 (br d, JPP = 30 and 485 Hz,
o-metallated phosphite), 54.7 (br d, JPP = 485 Hz, trans-PPh),
3
Ar–H), 7.40 (dd, 2H, JHH = 5 and 9 Hz, Ar–H), 7.12–7.55 (m,
47.1 (br s, cis-PPh), −17.5 (br s, free PPh2), −143.0 (heptet, JFP
=
1
30H, Ar–H), 7.94 (m, 1H, Ar–H). 31P{ H} NMR (CDCl3, 121.5
710 Hz, PF6). 13C{ H} NMR (CDCl3, 75 MHz): (6b and 10) d
27.9, 28.6, 30.3, 30.4, 31.5, 32.3, 33.2, 33.5, 36.5, 36.9, 37.3, 37.6,
121.4 (d, JPC = 11 Hz, Ar C), 121.8 (d, JPC = 11 Hz, Ar C), 125.2,
125.4, 126.1, 127.3, 131.3, 131.5, 131.7, 131.8, 131.9, 132.8, 133.1,
133.6, 134.3, 134.5, 134.7, 134.9, 136.0, 138.1, 139.1, 140.6, 149.0,
150.2, 150.9 (d, JPC = 11 Hz, Ar C).
1
MHz): d 137.5 (dd, JPP = 32 and 500 Hz, o-metallated phosphite),
18.3 (dd, JPP = 60 and 500 Hz, trans-PPh2), 2.4 (dd, JPP = 32 and
60 Hz, cis-PPh2), −28.1 (br s, free PPh2), −143.0 (heptet, JFP
=
710 Hz, PF6). 13C{ H} NMR (CDCl3, 75 MHz): d 30.5 (s, CH3),
31.4 (s, tBu CH3), 32.4 (s, tBu CH3), 33.1 (s, tBu CH3), 33.6 (s, tBu
CH3), 36.7 (s, C(CH3)3), 37.0 (s, C(CH3)3), 37.1 (s, C(CH3)3), 37.4
(s, C(CH3)3), 40.7 (t, JPC = 8 Hz, CCH3), 42.7 (d, JPC = 20 Hz,
PCH2), 121.3 (d, JPC = 12 Hz, Ar C), 125.7 (s, Ar CH), 127.6 (s,
Ar CH), 128.3 (s, Ar CH), 131.7 (s, Ar CH), 131.1 (s, Ar CH),
131.6 (s, Ar CH), 131.7 (s, Ar CH), 131.9 (s, Ar CH), 134.1 (s, Ar
CH), 135.0 (s, Ar CH), 135.6 (s, Ar CH), 136.1 (s, Ar C), 136.5 (s,
Ar C), 139.5 (s, Ar CH), 141.3 (d, JPC = 5 Hz, Ar C), 145.6 (s, Ar
C), 147.8 (s, Ar C), 149.8 (s, Ar C), 149.9 (s, Ar C), 150.5 (s, Ar
C), 154.6 (d, JPC = 24 Hz, Ar C).
1
Reaction of a mixture of complexes 6b and 10 with [AuCl(tht)].
A mixture of complexes 6b and 10 obtained above (0.099 g,
0.070 mmol) and [AuCl(tht)] (0.023 g, 0.070 mmol) was dissolved
in CH2Cl2 (15 mL) and stirred for 1 h at room temperature.
The solvent was removed in vacuo and the crude product was
recrystallised from CH2Cl2–hexane to give an off-white powder.
Yield: 0.071 g (65%). Anal. Calcd for C76H95AuClF6O3P5Pd: C,
1
54.8; H, 5.8%. Found: C, 55.6; H, 6.3%. 11a (∼50%): H NMR
(CDCl3, 300 MHz): d0.65 (s, 9H, C(CH3)3 o-metallated ring), 0.82
(s, 9H, C(CH3)3 o-metallated ring), 1.14 (s, 18H, C(CH3)3), 1.25
(s, 18H, C(CH3)3), 2.29–2.88 (m, 8H, 4 × PCH2), 6.80–6.95 (m,
4H, Ar–H), 6.99–7.12 (m, 6H, Ar–H), 7.18–7.63 (m, 22H, Ar–
Oxidation of complex 12a with hydrogen peroxide. Complex
12a (0.030 g, 0.02 mmol) was dissolved in CH2Cl2 (10 mL) and
stirred vigorously with H2O2 (30% w/w solution in water, 10 mL)
at room temperature for 18 h. The solution was then diluted with
water (50 mL) and the product extracted with CH2Cl2 (2 × 50 mL).
The combined organic extracts were dried (MgSO4) and the
solvent removed under reduced pressure to give an off-white solid
(0.025 g, 80%). Crystals of 13a suitable for X-ray analysis were
grown from CH2Cl2–hexane. Anal. Calcd for C83H101F6O4P5Pd:
3
H), 7.72 (dd, 2H, JHH = 7 and 8 Hz, Ar–H o-metallated ring).
1
31P{ H} NMR (CDCl3, 121.5 MHz): d 141.2 (dd, JPP = 35 and
500 Hz, o-metallated phosphite), 54.3 (dd, JPP = 30 and 500 Hz,
trans-PPh2), 41.0 (ddd, JPP = 30, 35 and 40 Hz, cis-PPh), 34.2
(d, JPP = 40 Hz, Ph2PAuCl), −143.0 (heptet, JFP = 710 Hz, PF6).
11b (∼50%): 1H NMR (CDCl3, 300 MHz): d 0.92 (s, 9H, C(CH3)3
o-metallated ring), 0.97 (s, 9H, C(CH3)3 o-metallated ring), 0.81
(s, 18H, C(CH3)3), 1.18 (s, 9H, C(CH3)3 o-metallated ring), 1.23
(s, 18H, C(CH3)3), 2.29–2.88 (m, 8H, 4 × PCH2), 6.80–6.95 (m,
4H, Ar–H), 6.99–7.12 (m, 6H, Ar–H), 7.18–7.63 (m, 21H, Ar–H),
1
C, 64.8; H, 6.6%. Found: C, 65.6; H, 7.1%. H NMR (CDCl3,
300 MHz): d 0.63 (br s, 3H, CH3), 0.96 (s, 9H, C(CH3)3 o-
metallated ring), 0.98 (s, 9H, C(CH3)3 o-metallated ring), 1.38 (s,
18H, C(CH3)3), 1.42 (s, 18H, C(CH3)3), 2.33–2.58 (m, 2H, PCH2),
2.71–3.03 (m, 4H, PCH2), 6.90 (m, 1H, Ar–H), 6.97–7.22 (m, 6H,
Ar–H), 7.30–7.51 (m, 16H, Ar–H), 7.53–7.66 (m, 6H, Ar–H),
7.68–7.84 (m, 6H, Ar–H), 8.01 (m, 2H, Ar–H), 8.24 (m, 2H, Ar–
1
7.72 (dd, 2H, 3JHH = 7 and 8 Hz, Ar–H o-metallated ring). 31P{ H}
NMR (CDCl3, 121.5 MHz): d 137.8 (dd, JPP = 32 and 505 Hz,
o-metallated phosphite), 60.4 (ddd, JPP = 30, 53 and 505 Hz, trans-
1
H). 31P{ H} NMR (CDCl3, 121.5 MHz): d 138.1 (dd, JPP = 32 and
464 | Dalton Trans., 2007, 459–466
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1
(br s, 3 × PPh2), −143.0 (heptet, JFP = 710 Hz, PF6). 31P{ H}
500 Hz, o-metallated phosphite), 28.4 (br s, P(O)Ph2), 17.9 (ddd,
JPP = 4, 63 & 500 Hz, trans-PPh2), 1.0 (ddd, JPP = 4, 32 and 63 Hz,
NMR (CD2Cl2, 162 MHz, 183 K): d 132.2 (dd, JPP = 35 and
511 Hz, o-metallated phosphite), 12.9 (dd, JPP = 55 and 511 Hz,
trans-PPh2), −2.8 (dd, JPP = 35 and 55 Hz, cis-PPh2), −30.2 (br s,
1
cis-PPh2), −143.0 (heptet, JFP = 710 Hz, PF6). 13C{ H} NMR
(CDCl3, 75 MHz): d 29.0, 29.4, 30.3, 30.5, 31.0, 31.6, 31.7, 35.0,
35.2, 38.9, 119.3, 123.4 (d, J = 8 Hz, Ar C), 123.8 (d, J = 8 Hz,
Ar C), 128.7, 128.8, 128.9, 129.0, 129.1, 129.2, 129.4, 130.0, 130.3,
130.4, 130.5, 131.1, 131.5, 131.8, 132.5, 132.6, 134.4, 134.5, 134.6,
135.8, 136.0, 147.0, 147.2, 147.6, 147.7, 151.5 (d, JPC = 10 Hz,
Ar C)
free PPh2), −143.0 (heptet, JFP = 710 Hz, PF6). 31P{ H} NMR
1
(CDCl3, 162 MHz, 333 K): d 130.5 (q, JPP = 160 Hz, o-metallated
phosphite), −4.2 (br d, JPP = 160 Hz, 3 × PPh2), −143.0 (heptet,
JFP = 710 Hz, PF6). 31P{ H} NMR (d8-toluene, 162 MHz, 383
1
K): d 130.2 (q, JPP = 165 Hz, o-metallated phosphite), −4.2 (br
d, JPP = 165 Hz, 3 × PPh2), −143.0 (heptet, JFP = 710 Hz, PF6).
31P{ H} MAS NMR (162 MHz, spinning at 18 kHz): d 133.1 (d,
1
Preparation of [Pd{j2-P,C-(P(OC6H4)(OC6H5)2}{1,1,1-tris-
(diphenylphosphinomethyl)ethane}][PF6]. [{Pd(l-Cl){j2-P,C-
(P(OC6H4)(OC6H5)2}}2] (0.350 g, 0.388 mmol) and 1,1,1-
tris(diphenylphosphinomethyl)ethane (0.485 g, 0.776 mmol)
were dissolved in CH2Cl2 (15 mL), then allowed to stir at room
temperature for 1 h. [NH4][PF6] (0.126 g, 0.776 mmol) was then
added, causing immediate precipitation of NH4Cl. The solution
was stirred at room temperature for 1 h and then filtered through
Celite. The solvent was removed under reduced pressure to give
an off-white solid. The crude product was then recrystallized from
CH2Cl2–hexane to give white crystals after drying in vacuo. Yield:
0.72 g (78%). Crystals suitable for X-ray analysis were grown
from CH2Cl2–hexane. Anal. Calcd for C59H53F6O3P5Pd: C, 59.8;
H, 4.5%. Found: C, 59.4; H, 4.7%. 1H NMR (CD2Cl2, 300 MHz):
JPP = 515 Hz, o-metallated phosphite), 10.7 (d, JPP = 515 Hz,
trans-PPh2), −2.6 (s, cis-PPh2), −34 (s, free PPh2), −143.1 (heptet,
JFP = 750 Hz, PF6). 13C{ H} NMR (CDCl3, 75 MHz): d 30.2 (s,
1
CH3), 40.7 (t, JPC = 8 Hz, CCH3), 42.5 (d, JPC = 20 Hz, PCH2),
112.6 (d, JPC = 5 Hz, Ar C), 120.8 (s, Ar CH), 120.9 (s, Ar CH),
123.7 (s, Ar CH), 126.6 (s, Ar CH), 129.4 (s, Ar CH), 129.5 (s, Ar
CH), 130.4 (s, Ar CH), 131.3 (s, Ar CH), 133.9 (s, Ar CH), 134.1
(s, Ar CH), 140.8 (s, Ar CH), 147.8 (s, Ar C), 149.9 (d, JPC
14 Hz, Ar C).
=
Oxidation
of
[Pd{j2-P,C-(P(OC6H4)(OC6H5)2}{1,1,1-
tris(diphenylphosphino-methyl)ethane}][PF6]. Complex
14
(0.100 g, 0.084 mmol) was dissolved in CH2Cl2 (10 mL) and
stirred vigorously with H2O2 (30% w/w solution in water, 10 mL)
at room temperature for 1 h. The solution was then diluted with
water (50 mL) and the product extracted with CH2Cl2 (2 ×
50 mL). The combined organic extracts were dried (MgSO4)
and the solvent was removed under reduced pressure to give
an off-white solid. Yield: 0.89 g (88%). Crystals suitable for
X-ray analysis were grown from CH2Cl2–hexane. Anal. Calcd
for C59H53F6O3P5Pd: C, 59.8; H, 4.5%. Found: C, 60.0; H, 4.7%.
1H NMR (CDCl3, 300 MHz): d 0.35 (br s, 3H, CH3), 2.57 (br d,
d 0.44 (br s, 3H, CH3), 2.41 (br s, 6H, PCH2), 6.34 (t, 1H, 3JHH
=
7 Hz, Ar–H o-metallated ring), 6.69 (d, 4H, 3JHH = 7 Hz, Ar–H),
6.83 (d, 1H, 3JHH = 7 Hz, Ar–H), 6.95 (t, 1H, 3JHH = 7 Hz, Ar–H),
1
7.11–7.49 (m, 37H, Ar–H). H NMR (CDCl3, 300 MHz): d 0.35
(br s, 3H, CH3), 2.53 (br s, 6H, PCH2), 6.31 (t, 1H, 3JHH = 7 Hz,
3
Ar–H o-metallated ring), 6.64 (d, 4H, JHH = 7 Hz, Ar–H), 6.74
(d, 1H, 3JHH = 7 Hz, Ar–H), 6.90 (t, 1H, 3JHH = 7 Hz, Ar–H), 7.10
(t, 2H, 3JHH = 7 Hz, Ar–H), 7.12–7.33 (m, 23H, Ar–H), 7.39–7.56
1
(m, 12H, Ar–H). 31P{ H} NMR (CD2Cl2, 121.5 MHz, 298 K):
2
d 131.0 (pseudo q, JPP = 110 Hz, o-metallated phosphite), −4.2
2H, JHP = 9 Hz, CH2P(O)Ph2), 2.77–3.13 (m, 4H, CH2PPh2),
Table 1 The data collection and refinement parameters of complexes 6a, 12b and 13a
6a
12b
13a
Empirical formula
Formula weight
Crystal system
Space group
C52H47O3P4Pd·SbF6·CH2Cl2
C59H53O3P4Pd·PF6· CH2Cl2
1270.19
Triclinic
P-1
10.294(2)
15.290(3)
18.798(5)
105.391(15)
93.38(2)
94.90(2)
2832.0(11)
2
C83H101O4P4Pd·PF6
1537.89
Triclinic
P-1
14.3703(2)
18.2612(2)
19.3131(2)
71.258(7)
74.580(5)
82.499(5)
4620.97(5)
2
1239.88
Monoclinic
P21/c
˚
a/A
12.7089(13)
24.953(3)
16.2793(19)
90
94.354(10)
90
5147.8(10)
4
1.600
˚
b/A
˚
c/A
a/◦
b/◦
c /◦
3
˚
Volume/A
Z
Density (calc)/Mg m−3
Absorption coefficient/mm−1
F(000)
1.490
0.628
1296
1.105
0.340
1612
1.135
2484
Crystal size/mm
0.4 × 0.2 × 0.2
0.2 × 0.14 × 0.04
0.15 × 0.1 × 0.1
◦
hmax
/
27.5
27.5
24.55
Reflections collected
64191
9220
0.0495
58599
10693
0.0389
14919
10072
0.0557
Independent reflections (I > 2rI)
R(int)
Final R indices F2 > 2rF2
R1
0.0384
0.0839
1.236/−1.361
0.0462
0.1113
1.466/−1.123
0.0608
0.1255
0.932/−0.558
wR2
Dq max/min/e A
−3
˚
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©

View Article Online
3
6.33 (t, 1H, JHH = 8 Hz, Ar–H ortho-metallated ring), 6.66 (d,
Acknowledgements
3
3
4H, JHH = 8 Hz, Ar–H), 6.80 (d, 2H, JHH = 7 Hz, Ar–H),
3
We thank the EPSRC for funding and the provision of an
Advanced Research Fellowship (RBB) and Johnson Matthey for
the loan of palladium salts.
6.92 (t, 1H, JHH = 6 Hz, Ar–H), 7.07–7.51 (m, 36H, Ar–H),
3
7.69 (m, 6H, Ar–H), 7.85 (dd, 2H, JHH = 6 and 12 Hz, Ar–H).
31P{ H} NMR (CDCl3, 121.5 MHz): d 131.6 (dd, JPP = 35 and
1
515 Hz, o-metallated phosphite), 28.3 (d, JPP = 5 Hz, P(O)Ph2),
13.0 (ddd, JPP = 5, 60 and 515 Hz, trans-PPh2), −2.2 (ddd, JPP
=
References
5, 35 and 60 Hz, cis-PPh2), −143.0 (heptet, JFP = 710 Hz, PF6).
1 Comprehensive Organometallic Chemistry II: a review of the literature
1982–1994, ed. E. W. Abel, F. G. A. Stone and G. Wilkinson, Pergamon,
Oxford, 1995.
2 (a) J. M. Vila, M. T. Pereira, J. M. Ortigueira, J. J. Ferna´ndez, A.
Ferna´ndez, M. Lo´pez-Torres and H. Adams, Organometallics, 1999, 18,
5484; (b) M. Lo´pez-Torres, A. Ferna´ndez, J. J. Ferna´ndez, A. Sua´rez,
M. T. Pereira, J. M. Ortigueira, J. M. Vila and H. Adams, Inorg. Chem.,
2001, 40, 4583.
13C{ H} NMR (CDCl3, 75 MHz): d 30.0 (s, CH3), 40.6 (t, JPC
=
1
8 Hz, CCH3), 42.0 (d, JPC = 20 Hz, PCH2), 43.6 (d, JPC = 11 Hz,
PCH2), 112.6 (d, JPC = 5 Hz, Ar C), 120.8 (s, Ar CH), 120.9 (s,
Ar CH), 123.7 (s, Ar CH), 126.6 (s, Ar CH), 129.4 (s, Ar CH),
129.5 (s, Ar CH), 130.4 (s, Ar CH), 131.3 (s, Ar CH), 133.9 (s, Ar
CH), 134.1 (s, Ar CH), 140.8 (s, Ar CH), 147.8 (s, Ar C), 149.9
(d, JPC = 14 Hz, Ar C).
3 A. Albinati, S. Affolter and P. S. Pregosin, Organometallics, 1990, 9,
379.
4 For recent examples see:(a) A. Enzmann, M. Eckert, W. Ponikwar, K.
Polborn, S. Schneiderbauer, M. Beller and Wolfgang Beck, Eur. J. Inorg.
Chem., 2004, 1330; (b) A. Ferna´ndez, D. Va´zquez-Garc´ıa, J. J.
Ferna´ndez, M. Lo´pez-Torres, A. Sua´rez, S. Castro-Juiz and J. M. Vila,
Eur. J. Inorg. Chem., 2002, 2389; (c) A. Ferna´ndez, J. J. Ferna´ndez, M.
Lo´pez-Torres, A. Sua´rez, J. M. Ortigueira, J. M. Vila and H. Adams,
J. Organomet. Chem., 2000, 612, 85; (d) M. Lousame, A. Ferna´ndez,
M. Lo´pez-Torres, D. Va´zquez-Garc´ıa Jose´, M. Vila, A. Sua´rez, J. M.
Ortigueira and J. J. Ferna´ndez, Eur. J. Inorg. Chem., 2000, 2055.
5 R. B. Bedford, S. L. Hazelwood, M. E. Limmert, D. A. Albisson, S. M.
Draper, P. N. Scully, S. J. Coles and M. B. Hursthouse, Chem.–Eur. J.,
2003, 3126.
X-Ray crystallography
The data collection and refinement parameters of structures 6a,
12b and 13a are presented in Table 1. X-Ray diffraction data were
collected by means of combined phi and omega scans on a Bruker-
Nonius KappaCCD area detector situated at the window of a
˚
rotating anode (k Mo Ka= 0.71073 A). The structures were solved
by direct methods, SHELXS-97 and refined using SHELXL-97.9
Hydrogen atoms were included in the refinement, but thermal
parameters and geometry were constrained to ride on the atom
to which they are bonded. The data were corrected for absorption
effects using SADABS.10 Crystals of 13a gave poor datasets and the
resulting structure exhibits disorder in the SbF6 moiety. There are
also signs of disorder in the methyl groups and accordingly atom
C47 was only refined isotropically as two independent sites could
not be identified and refined anisotropically. There is also a large
void in this structure, however the data are not of sufficient quality
to reveal any residual electron density that could be assigned to any
species. CCDC reference numbers 207765, 223269 and 624071. For
crystallographic data in CIF or other electronic format see DOI:
10.1039/b613524b
6 D. A. Albisson, R. B. Bedford, S. E. Lawrence and P. N. Scully, Chem.
Commun., 1998, 2095.
7 This assignment is made on the basis of a comparison of the chemical
shift and coupling of the coordinated diphenylphosphino residue(s) of
the oxides 8a, 8b and the gold chloride adducts 9a, 9b.
8 For examples of the more typical j2-P,P-bonding mode of
1,1,1-tris(diphenylphosphinomethyl)ethane see:(a) P. Sevillano, A.
Habtemariam, M. I. Garc´ıa Seijo, A. Castin˜eiras, S. Parsons, M. E.
Garc´ıa and P. J. Sadler, Aust. J. Chem., 2000, 53, 635; (b) M.-A. David,
D. K. Wicht, D. S. Glueck, G. P. A. Yap, L. M. Liable-Sands and A. L.
Rheingold, Organometallics, 1997, 16, 4768; (c) A. F. Chiffey, J. Evans
and W. Levason, Polyhedron, 1996, 15, 1309.
9 G. M. Sheldrick, 1997, SHELX97: Programs for structure solution and
refinement, University of Go¨ttingen: Germany.
10 G. M. Sheldrick, 2003, SADABS. Version, 2.10, Bruker AXS Inc.:
Madison, Wisconsin, USA.
466 | Dalton Trans., 2007, 459–466
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