Bis(phosphine) derivatives of diamines

Article abstract of DOI:10.1016/j.poly.2003.11.048

The synthesis, oxidation and coordination chemistry of new bis(aminophosphines) based on diamines is demonstrated. Ph₂PN(CH ₂Ph)CH₂CH₂(CH₂Ph)NPPh₂, ⁱPr₂PN(CH₂

Full text of DOI:10.1016/j.poly.2003.11.048

Polyhedron 23 (2004) 693–699
www.elsevier.com/locate/poly
Bis(phosphine) derivatives of diamines
Mireia Rodriguez I. Zubiri, Heather L. Milton, David J. Cole-Hamilton,
*
Alexandra M.Z. Slawin, J. Derek Woollins
School of Chemistry, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK
Received 11 October 2003; accepted 19 November 2003
Abstract
The synthesis, oxidation and coordination chemistry of new bis(aminophosphines) based on diamines is demonstrated.
Ph2PN(CH2Ph)CH2CH2(CH2Ph)NPPh2, iPr2PN(CH2Ph)CH2CH2(CH2Ph)NPiPr2, Ph2PNH(C10H6)2NHPPh2, Ph2PNH(C10H6)
(C6H4)NHPPh2 were prepared and tested in the hydroformylation of hex-1-to give aldehydes with poor selectivity (up to l:b ¼ 2.5:1)
to the desired linear products. Modelling calculations were performed for all ligands. R2 groups enlarge the natural bite angle when
going from R2 ¼ Ph2 to R2 ¼ iPr2 which are more bulky. Most of the ligands seem to be rigid (with flexibility ranges of 25°–46°).
Four demonstrative X-ray structures are reported.
Ó 2003 Elsevier Ltd. All rights reserved.
Keywords: Ligand; Catalysis; X-ray structure; Complex
1. Introduction
on the regioselectivity of rhodium catalysed hydro-
formylation of alkenes. Continuing our studies on the
preparation of potentially active ligands for homoge-
neous catalysis, we investigated the synthesis, oxidation
and coordination chemistry of new bis(aminophos-
phines) based on simple diamines in anticipation that
the resulting phosphines will have different steric and
electronic properties. Here, we report the synthesis of
two new phosphines together with hydroformylation
studies and four demonstrative X-ray structures.
Hydroformylation of alkenes is a very important
catalytic reaction in industry and great effort has been
devoted to obtaining highly active and selective catalysts
[1–6]. This is a very important area of investigation since
it has been extensively reported that selective catalytic
processes are affected by many factors such as the con-
figuration that the ligand may have, i.e., its bite angle
and its range of flexibility and the electronic properties
of the ligands when binding the precursor metal species
[7–12]. These factors influence the direction of approach
of the substrate to the active catalyst and therefore the
selectivity of the reaction.
2. Results and discussion
Reaction of N,N0-dibenzylethylenediamine with two
equivalents of R2PCl gives 1 and 2 (Eq. (1)). 1 was first
prepared by Payne and Stephan [23] and later by Bala-
krishna et al. [24]. However, they did not report IR or
FABþ mass spectrometry data and neither did they
study its oxidation chemistry nor its activity in homo-
geneous catalysis. Therefore, we considered it to be of
interest to study this compound further, including the
preparation of its diselenide derivative and the study of
its activity in rhodium catalysed hydroformylation of
alkenes whilst 2 offers a steric and electronic variant in
this regard.
By altering the substituents on the phosphorus atoms
and keeping the same diamine backbone (piperazine and
homopiperazine) [13,14] we were able to conduct a
systematic study on the electronic and steric effects of a
wide range of the bis(aminophosphines) derivatives of
piperazine and homopiperazine. In recent work [13–22],
we studied synthesis of new P–N containing ligands and
the effect of the electronic properties of different ligands
* Corresponding author. Tel.: +44-1334-463869; fax: +44-1334-
463384.
E-mail address: jdw3@st-andrews.ac.uk (J. Derek Woollins).
0277-5387/$ - see front matter Ó 2003 Elsevier Ltd. All rights reserved.
doi:10.1016/j.poly.2003.11.048

694
M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
centres have trigonal character (P–N–C angles are closer
to 120° than 109°) though the P–N bond is quite long.
Reaction of (S)-())-1,10 -binaphthyl-2,20 -diamine and
1-(2-aminophenyl)-2-naphthalene with two equivalents
of Ph2PCl, after deprotonation by nBuLi, proceeds in
thf to give Ph2PNH(C10H6)2NHPPh2 (3) (BDPAB) and
Ph2PNH(C10H6)(C6H4)NHPPh2 (4), respectively (Eq.
(2))
ð1Þ
FABþ mass spectrometry confirms the proposed
identity of the ligands by showing the expected parent-
ion peaks and elemental analysis data is in agreement
with calculated values.
The 31P{1H} NMR spectrum of 2 displays a singlet at
d (P) 89.1 ppm, the large downfield shift when compared
to 1 (d (P) 66.5 ppm) reflecting the close proximity of the
phosphorus centres to the isopropyl substituents in 2
instead of the phenyl groups in 1.
Crystals of compound 2 (Fig. 1) suitable for X-ray
analysis were obtained by recrystallisation of the com-
pound from hot toluene. The molecular structure shows
that the P–N bonds adopt a trans orientation relative to
one another. The molecule has a centre of symmetry
and, thus, the bond lengths and angles are equal for the
two halves of the molecule. P–N bond lengths are typ-
ical for this type of compound. The phosphorus atoms
adopt a flattened tetrahedral geometry with C–P–N
angles somewhat less than 109°, whilst the nitrogen
ð2Þ
The 31P{1H} NMR spectrum of 3 comprises a singlet
at d (P) 27.7 ppm. The identity of this compound is
supported by FABþ mass spectrometry (m=z 652 [Mþ])
and the IR spectrum, because a band associated with a
m(N–H) stretch (3330 cmꢀ1) is observed. H NMR and
1
elemental analysis data are in agreement with the liter-
ature. It presents interesting characteristics such as its
structural rigidity and chirality and, although it is not a
new bis(aminophosphine) [25,26], we considered it im-
portant to study it because its, the ligand had not been
tested in the rhodium catalysed hydroformylation of
alkenes. Recrystallisation from hot toluene gives 3 as
colourless crystals. The X-ray structure (Fig. 2) reveals
Fig. 2. Solid state structure of Ph2PNH(C10H6)2NHPPh2 3. Selected
Fig. 1. Solid state structure of iPr2PN(CH2Ph)CH2CH2
bond lengths (A) and angles (°) P(1)–N(1) 1.7043(19), P(1)–C(25)
ꢀ
(CH2Ph)NPiPr2 2. Selected bond lengths (A) and angles (°) N(1)–P(1)
1.836(2), P(1)–C(19) 1.835(2), N(1)–C(2) 1.402(3), C(5)–N(6) 1.403(3),
N(6)–C(6) 1.7115(18), N(1)–P(1)–C(25) 103.32(10), N(1)–P(1)–C(19)
99.54(10), C(25)–P(1)–C(19) 101.25(10), C(2)–N(1)–P(1) 125.33(16)
C(5)–N(6)–P(6) 126.38(15), N(6)–P(6)–C(7) 99.73(9), N(6)–P(6)-C(13)
102.33(10), C(7)–P(6)–C(13) 99.68(10).
ꢀ
1.704(2), P(1)–C(13) 1.850(3), P(1)–C(10) 1.856(3), N(1)–C(3) 1.466(3),
C(3)–N(1)–C(2) 114.9(2), C(3)–N(1)–P(1) 116.26(17), C(2)–N(1)–P(1)
123.11(17), N(1)–P(1)–C(13) 100.49(13), N(1)–P(1)–C(10) 105.72(12),
C(13)–P(1)–C(10) 102.85(17).

M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
695
an interesting orientation of the naphthyl rings of the
amine backbone relative to one another with a dihedral
angle of 98° P–N bond lengths are typical for this type
of compound. The two nitrogen atoms in the molecule
adopt a geometry close to trigonal whilst, like 2 the
phosphorus centres are flattened from tetrahedral.
The magnitude of P–Se J values can be used to assess
the donor ability of phosphines [32,33] with better do-
nors having lower 1J{77Se–31P} values, as a consequence
of the degree of s character in the phosphorus lone pair,
etc., i.e., larger coupling constants imply more s char-
acter and a poorer donor. Reaction of 1 and 2 with two
equivalents of elemental selenium in toluene proceeds
smoothly to give Ph2P(Se)N(CH2Ph)CH2CH2(CH2Ph)
NP(Se)Ph2 (5) and iPr2P(Se)N(CH2Ph)CH2CH2(CH2
Ph)NP(Se)iPr2 (6). The 31P{1H} NMR spectra of 5 and
6 consist of singlets at d (P) 70.8 and d (P) 104.1 ppm,
respectively, shifted-downfield from the free ligand in
ular structure shows that the P@Se bonds adopt a trans
orientation relative to one another. The P–N bond is
significantly shorter in this P(V) compound compared to
the parent P(III) system which is somewhat counter-
intuitive and suggests that in 2 there may be some an-
tibonding p character in the P–N linkage. The P@Se
bond lengths are typical for this type of compound. The
phosphorus atoms are close to tetrahedral – implying
that the selenium atom in 6 is less stereochemically
active than the lone pair in 2.
Reaction of
[PtCl2(cod)] in dichloromethane gives the seven-mem-
2
with equimolar quantities of
bered,
P
P0 chelate cis-[PtCl2{iPr2PN(CH2Ph)CH2
CH2N(CH2Ph)PiPr2}] 7.
1
both cases, with J(77Se–31P) coupling constants of 777
and 741 Hz, respectively, which are in accord with val-
ues previously reported for similar selenides [27–31] and
suggest that as expected 2, with electron donating alkyl
groups, is the better donor system.
5 and 6 show, in their IR spectra, bands that can be
assigned to m(P–N) [943 cmꢀ1 for 5 and 936 cmꢀ1 for 6]
and m(P–Se) at 557 cmꢀ1 for 5 and 594 cmꢀ1 for 6.
Slow diffusion of diethyl ether into a dichlorome-
thane solution of 6 gives the product as colourless
crystals suitable for X-ray analysis (Fig. 3). The molec-
as a colourless solid in good yield (82%).
The 31P{1H} NMR spectrum of 7 consists of a singlet
(d (P) 86.7 ppm) with a 1J(195Pt–31P) coupling constants
of 4106 Hz. The analogous platinum complex with li-
gand 1 shows a very similar 1J(195Pt–31P) (4048 Hz) and
a singlet (d (P) 59.1 ppm) at almost 27 ppm upfield be-
cause of the presence of phenyl groups on the phos-
phorus atoms instead of the more electron donating
isopropyl groups present in 7.
FABþ mass spectrometry does not show the parent-
ion peak and shows instead fragmentation patterns con-
sistent with the loss of one or two chloride ions (m=z) 702/
3 [M–Clꢀ] and 666/8 [M–2Clꢀ] and the IR spectrum of 7
shows bands for m(P–N) (887 cmꢀ1) and m(Pt–Cl) (337 and
326 cmꢀ1) which supports the cis geometry of 7.
Recrystallisation from hot toluene gives 7 as colour-
less crystals suitable for X-ray analysis. The X-ray
structure of 7 (Fig. 4 and Table 2) reveal that the ligand
is bound in a bidentate coordination mode to the plat-
inum centre with cis geometry. The complex forms a
seven-membered Pt–P–N–C–C–N–P ring and the metal
has distorted square planar geometry because the bite
angle of the ligand is larger than the ideal 90° and Cl–
Pt–Cl is smaller than 90°. The P–N distances are typical
of a single bond and are, as was the case for 6, shorter
than that in 2 (see Fig. 4).
Fig. 3. Solid state structure of iPr2P(Se)N(CH2Ph)CH2CH2
i
ꢀ
(CH2Ph)NP(Se) Pr2 6. Selected bond lengths (A) and angles (°): Se(1)–
P(1) 2.1115(10), P(1)–N(1) 1.679(3), P(1)–C(10) 1.822(4), P(1)–C(13)
1.853(4), N(1)–C(3) 1.477(4), N(1)–C(2) 1.475(4), N(1)–P(1)–C(10)
105.63(18), N(1)–P(1)–C(13) 109.80(17), C(10)–P(1)–C(13) 107.1(2),
N(1)–P(1)–Se(1) 111.94(11), C(10)–P(1)–Se(1 )111.31(15), C(13)–P(1)–
Se(1) 110.86(13), C(3)–N(1)–C(2) 114.3(3), C(3)–N(1)–P(1) 118.9(2),
C(2)–N(1)–P(1) 121.2(2).

696
M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
Ligands 1–4 were tested in the rhodium catalysed
hydroformylation of hex-1-ene using a simple batch
autoclave (Table 1) Generally the linear:branched se-
lectivity is not particular impressive. We conducted
simple molecular modelling calculations (Spartan Pro)
of the natural bite angle (bn) according to the method of
Casey and co-workers [34,35] as well as the flexibility
range of the ligand (Table 1) since van Leeuwen has
proposed that ligands with a natural bite angle of 112°–
120° favour equatorial–equatorial coordination during
the catalytic cycle and thus give better l:b ratios. We
have found a relatively poor correlation between natural
bite angle (which specifically ignores metal orbital elec-
tronic effects) and the real bite angles, although gener-
ally the so-called natural bite angle is somewhat larger
than either calculated or measured ÔrealÕ bite angle
[36,37]. The results obtained with the ligands 1–4 which
have natural bite angles in the range 108.9°–127.7° do
not support the hypothesis that there is a correlation
between bite angle and selectivity (see Table 2).
Fig. 4. Solid state structure of cis-[PtCl2{iPr2PN(CH2Ph)CH2CH
i
ꢀ
2N(CH2Ph)P Pr2}] 7. Selected bond lengths (A) and angles (°): Pt(1)–
P(21) 2.2531(8), Pt(1)–P(1) 2.2594(8), Pt(1)–Cl(1) 2.3724(8), Pt(1)–
Cl(2) 2.3777(8), P(1)–N(1) 1.6843(19), P(1)–C(10) 1.844(3), P(1)–C(13)
1.888(2), N(1)–C(3) 1.467(3), N(1)–C(2) 1.489(3), P(21)–Pt(1)–P(1)
100.64(3), P(21)–Pt(1)–Cl(1) 174.60(3), P(1)–Pt(1)-Cl(1) 84.74(3),
P(21)–Pt(1)–Cl(2) 88.64(3), P(1)–Pt(1)–Cl(2) 170.44(2), Cl(1)–Pt(1)–
Cl(2) 86.01(3), N(1)–P(1)–C(10) 103.84(12), N(1)–P(1)–C(13)
101.26(11), C(10)–P(1)–C(13) 106.58(12), N(1)–P(1)–Pt(1) 123.57(8),
C(10)–P(1)–Pt(1) 107.82(9), C(13)–P(1)–Pt(1) 112.42(9), C(3)–N(1)–
This work illustrates the usefulness of P–N contain-
ing ligands in hydroformylation, in particular the ease of
the simple P–N bond forming reaction enables rapid
screening of different ligand bite angles and electronic
properties. Further work is in progress.
C(2) 112.06(19),
119.13(17).
C(3)–N(1)–P(1)
122.52(16),C(2)–N(1)–P(1)
Table 1
Hydroformylation of oct-1-ene catalysed by rhodium complexes with batch autoclave test unit at 100 °C and 20 bar CO/H2 (1:1); all reactions gave
100% conversion
Compound
Formula
Time (h)
Selectivity to
aldehyde %
l:b
bn
Flexibility
range
1
2
3
4
Ph2PN(CH2Ph)CH2CH2(CH2Ph)NPPh2
iPr2PN(CH2Ph)CH2CH2(CH2Ph)NPiPr2
Ph2PNH(C10H6)2NHPPh2
22.2
5
79.8
78.4
94.5
86.1
1.9:1
1.2:1
1.8:1
2.3:1
108.9
127.7
120
28
25
46
33
13.9
13.9
Ph2PNH(C10H6)(C6H4)NHPPh2
115.5
b is the natural bite angle [35].
Table 2
Details of the X-ray data collections and refinements
Compound (local ID number)
2
3
6
7
Empirical formula
M
C
472.6
28H46N2P2
C44H34N2P2
652.7
triclinic
C28H46N2P2Se2
630.5
orthorhombic
C28H46N2P2Cl2Pt
738.6
Crystal system
Space group
triclinic
ꢁ
monoclinic
P2ð1Þ=n
ꢁ
P1
P1
Pbca
ꢀ
a (A)
8.392(2)
9.344(4)
11.192(5)
87.53(4)
76.43(3)
61.64(2)
748
10.4672(19)
11.128(2)
15.555(3)
89.499(3)
85.136(3)
71.093(3)
1708
16.1838(7)
13.6979(6)
14.2025(7)
10.308(2)
22.822(4)
13.710(3)
ꢀ
b (A)
ꢀ
c (A)
a (°)
b (°)
c (°)
110.145(2)
3
ꢀ
U (A )
3148
4
1.330
3028
4
1.620
Z
1
1.049
2
1.269
Dc (g cmꢀ3
)
l (mmꢀ1
T (K)
Reflections measured
)
0.162
293
0.162
125
2.468
293
4.936
125
2263
1561(0.0174)
0.0464, 0.1174
8538
4776(0.0245)
0.0389, 0.0951
12,551
2229(0.1166)
0.0352, 0.0841
13,700
3924(0.1381)
0.0531, 0.1147
Independent reflections (Rint
Final R1, wR2 ½I > 2rðIÞꢁ
Þ

M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
697
3. Experimental
cipitated, was removed by filtration under nitrogen and
then the volatiles were evaporated in vacuo to leave a
white solid. Recrystallisation from ethanol–benzene
gave white crystals. 31P{H} NMR (CDCl3): 27.7 (s)
ppm. IR, Mass Spectroscopy, H NMR and elemental
analysis are in agreement with literature data.
General conditions for the syntheses and catalytic
studies were as previously described [13,14].
1
Ph2PN(CH2Ph)CH2CH2(CH2Ph)NPPh2 1 was pre-
pared following the procedure of Balakrishna et al. [24].
A dry and degassed Et2O (20 ml) solution of chlo-
rodiphenylphosphine (3.2 ml, 3.95 g, 17.95 mmol) was
added dropwise over a period of 30 min to a stirred
solution of N,N0 -dibenzylethylenediamine (2.050 g, 8.51
mmol) and triethylamine (2.4 ml, 1.72 g, 16.99 mmol) in
dry and degassed Et2O (20 ml) at 0 °C. Stirring was
continued overnight, during which time a white precip-
itate separated from the colourless solution. This pre-
cipitate was isolated by suction filtration and
consecutively washed with water, methanol and diethyl
ether. The product was dried under vacuum to give a
white solid which was crystallised from CH2Cl2–hexane.
Yield: 4.25 g, 82%; Microanalysis: Found: (Anal. Calc.)
C, 78.6 (78.9); H, 6.7 (6.3); N, 4.7 (4.6)%; 31P{H} NMR
(CDCl3): 66.5 (s) ppm; Selected IR data (KBr): m(PN)
916 cmꢀ1; FABþ MS: m/z 610 [M+H]þ, 632 [M+Naþ].
(iPr)2PN(CH2Ph)CH2CH2(CH2Ph)NP(iPr)2 2. A
dry and degassed Et2O (10 ml) solution of chlorodiiso-
propylphosphine (3.5 ml, 3.386 g, 22.00 mmol) was ad-
ded dropwise over a period of 30 min to a stirred
solution of N,N0 -dibenzylethylenediamine (2.5 ml, 2.644
g, 11.00 mmol) and triethylamine (3.1 ml, 2.23 g, 22.00
mmol) in dry and degassed Et2O (40 ml). Stirring was
continued for 5 days. The solution was evaporated to
dryness in vacuo and thf (30 ml) was added. Triethy-
lammonium hydrochloride separated from the colour-
less solution. This precipitate was removed by suction
filtration under nitrogen. The filtrate was evaporated to
dryness in vacuo to give a yellowish oil. Crystallisation
from hot toluene gave white crystals.: Yield: 2.391 g,
46%; Microanalysis: Found: (Anal. Calc.) C, 70.7 (71.2);
H, 10.3 (9.8); N 5.8 (5.9)%; 31P{H} NMR (CDCl3): 89.1
(s) ppm; FABþ MS: m/z 473 [M+Hþ].
Ph2PNH(C10H6)(C6H4)NHPPh2 4. A dry and de-
gassed thf (25 ml) solution of 1-(2-aminophenyl)-2-
naphthylamine (0.998 g, 4.26 mmol) was cooled to )78
°C in an acetone–dry Ice bath. To the cooled solution
was added dropwise a hexane solution of BuLi (3.6 ml,
2.5 mol dmꢀ3, 8.91 mmol) over 50 min. After the ad-
dition, the mixture was stirred at )78 °C for 1 h and
another 30 additional min at room temperature. The
reaction solution was cooled to )78 °C again and to it
was added dropwise a solution of diphenylchlorophos-
phine (1.6 ml, 1.928 g, 8.74 mmol) dissolved in thf (10
ml) over 1 h. Stirring was continued for another 1 h at
)78 °C. Then the cooling bath was removed and the
mixture was stirred overnight at room temperature. The
solution was evaporated to dryness in vacuo and di-
chloromethane (30 ml) was added. Lithium chloride,
which precipitated, was removed by filtration under ni-
trogen and then the volatiles were evaporated in vacuo
to leave a white solid. Yield: 2.362 g, 92%; Microanal-
ysis: Found: (Anal. Calc.) C, 79.4 (79.7); H, 5.2 (5.4); N,
1
4.6 (4.7)%; H NMR: d 7.86–6.86 ppm (m, 20 H, aro-
2
matic), 4.3 ppm (d, 1 H, J(PH) ¼ 78.3 Hz, NH), 4.7
ppm (d, 1 H, 2J(PH) ¼ 78.3 Hz, NH); 31P{H} NMR
(CDCl3): 28.8 (s), 28.1 (s) ppm; Selected IR data (KBr):
m(NH) 3367 and 3322 cmꢀ1, m(PN) 891 and 889 cmꢀ1
;
FABþ MS: m/z 603 [M+Hþ].
Ph2P(Se)N(CH2Ph)CH2CH2(CH2Ph)NP(Se)Ph2
5. To a dry and degassed toluene (10 ml) solution of
selenium (0.026 g, 0.33 mmol) was added solid
Ph2PN(CH2Ph) CH2CH2(CH2Ph)NPPh2 (0.100 g, 0.16
mmol). The solution was heated to reflux for ca. 2–3 h
and allowed to cool to room temperature. The solution
was evaporated to dryness in vacuo and the solid was
dissolved in dichloromethane (2 ml). The dichlorome-
thane solution was filtered through Celite and diethyl
ether (20 ml) was added. The white product was col-
lected by suction filtration and washed with diethyl ether
(2 ꢂ 10 ml). Yield: 0.108 g, 88%; Microanalysis: Found:
(Anal. Calc.) C, 62.9 (62.7); H, 4.6 (5.0); N, 3.6 (3.6)%;
Ph2PNH(C10H6)2NHPPh2 3 was prepared following
the method of Miyano et al. [25,26].
A dry and degassed thf (10 ml) solution of (S)-())-
1,10 -binaphthyl-2,20 -diamine (0.446 g, 1.57 mmol) was
cooled to )78 °C in an acetone–dry Ice bath. To the
cooled solution was added dropwise a hexane solution
of BuLi (1.3 ml, 2.5 mol dmꢀ3, 3.28 mmol) over 30 min.
After the addition the mixture was stirred at )78 °C for
1 h and another 30 additional min at room temperature.
The reaction solution was cooled to )78 °C again and to
it was added dropwise a solution of diphenylchloro-
phosphine (0.6 ml, 0.709 g, 3.21 mmol) in thf (10 ml)
over 1 h. Stirring was continued for another 1 h at )78
°C. Then the cooling bath was removed and the mixture
was stirred overnight at room temperature. The solution
was evaporated to dryness in vacuo and dichlorome-
thane (30 ml) was added. Lithium chloride, which pre-
1
31P{H} NMR (CDCl3): 70.8 (s) ppm, J(77Se–31P) 777
Hz; Selected IR data (KBr): m(PN) 943 cmꢀ1, m(PSe) 557
cmꢀ1; FABþ MS: m/z 768 [M+Hþ].
(iPr)2P(Se)N(CH2Ph)CH2CH2 (CH2Ph)NP(Se)
(iPr)2 6. To a dry and degassed toluene (5 ml) solution
of selenium (0.055 g, 0.70 mmol) was added
(iPr)2PN(CH2Ph)CH2CH2(CH2Ph)NP(iPr)2 (0.165 g,
0.35 mmol) in toluene (5 ml). The solution was heated to
reflux for ca. 2–3 h and allowed to cool to room tem-
perature. The solution was evaporated to dryness in
vacuo and the solid was dissolved in dichloromethane

698
M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
(2 ml). The dichloromethane solution was filtered
through Celite and diethyl ether (20 ml) was added. The
white product was collected by suction filtration and
washed with diethyl ether (2 ꢂ 10 ml). Recrystallisation
from Toluene–hexane gave crystals. Yield: 0.159 g, 72%;
Microanalysis: Found: (Anal. Calc.) C, 53.8 (53.3); H,
7.7 (7.4); N, 4.4 (4.4)%; 31P{H} NMR (CDCl3): 104.1 (s)
ppm, 1J(77Se–31P) 741 Hz; Selected IR data (KBr):
m(PN) 936 cmꢀ1, m(PSe) 594 cmꢀ1; FABþ MS: m/z 630/2
[M], 655 [M+Naþ].
References
[1] S. Miyano, M. Nawa, A. Mori, H. Hashimoto, Bull. Chem. Soc.
Jpn. 57 (1984) 2171.
[2] (a) P.W.N.M. van Leeuwen, C.P. Casey, G.T. Whiteker,
Rhodium Catalysed Hydroformylation, in: P.W.N.M. van Leeu-
wen, C. Claver, Kluber Academic Publishers, Dordrecht, The
Netherlands, 2000 (Ch. 4);
(b) F. Agbossou, J.F. Carpentier, A. Mortreux, Chem. Rev. 95
(1995) 2485;
(c) M. Beller, B. Cornils, C.D. Frohning, C.W. Kohlpaintner,
J. Mol. Catal. A 104 (1995) 17.
cis-[PtCl2{(iPr)2PN(CH2Ph)CH2 CH2(CH2Ph)NP
(iPr)2}] 7. To a dichloromethane (10 ml) solution of
[PtCl2(cod)] (0.195 g, 0.52 mmol) was added (iPr)2PN
(CH2Ph)CH2CH2(CH2Ph)NP(iPr)2 (0.246 g, 0.52
mmol) in dichloromethane (5 ml) and the colourless
solution stirred for ca. 2–3 h. The solution was con-
centrated under reduced pressure to ca. 1 ml and diethyl
ether (10 ml) added. The white product was collected by
suction filtration and washed with diethyl ether (2 ꢂ 10
ml). Yield: 0.315 g, 82%; 31P{H} NMR (CDCl3): 86.7 (s)
ppm, 1J(195Pt–31P) 4106 Hz; Selected IR data (KBr):
m(PN) 887 cmꢀ1, m(PtCl) 337 and 326 cmꢀ1; FABþMS:
m/z 702/3 [M–Clꢀ], 666/8 [M–2Clꢀ].
Catalytic studies [Rh(acac)(CO)2] (0.01 mol dmꢀ3),
phosphine (0.023 mol dmꢀ3), hex-1-ene(1 cm3) were re-
acted in toluene (4 cm3) at 100 °C and 20 bar CO/H2
(1:1) for time stated in Table 1. The rhodium complex,
phosphine and toluene were heated at 100 °C and 14 bar
CO/H2 (1:1) for 45 min, to allow the active catalyst to
form before injection of the hex-1-ene and pressurising
to 20 bar.
[3] C.P. Casey, E.L. Paulsen, E.W. Beuttenmueller, B.R. Proft, B.A.
Matter, D.R. Powell, J. Am. Chem. Soc. 121 (1999) 63.
[4] C.P. Casey, G.T. Whiteker, M.G. Melville, L.M. Petrovich, J.A.
Gavney Jr., D.R. Powell, J. Am. Chem. Soc. 114 (1992) 5535.
[5] L.A. Van der Veen, M.D.K. Boele, F.R. Bregman, P.C.J. Kamer,
P.W.N.M. van Leeuwen, K. Goubitz, J. Fraanje, H. Schenk, C.
Bo, J. Am. Chem. Soc. 120 (1998) 11616.
[6] (a) P.W.N.M. van Leeuwen, C.F. Roobeek, J. Organomet. Chem.
258 (1983) 343;
(b) T. Jongsma, G. Challa, P.W.N.M. van Leeuwen, J. Organo-
met. Chem. 421 (1991) 121;
(c) A. van Rooy, E.N. Orij, P.C.J. Kamer, F. Van den Aardweg,
P.W.N.M. van Leeuwen, J. Chem. Soc., Chem. Commun. (1991)
1096;
(d) A. van Rooy, E.N. Orij, P.C.J. Kamer, P.W.N.M. van
Leeuwen, Organometallics 14 (1995) 34;
(e) M.P. Magee, W. Luo, W.H. Hersh, Organometallics 21 (2002)
362;
(f) B. Breit, R. Winde, T. Mackewitz, R. Paciello, K. Harms,
Chem. Eur. J. 7 (2001) 3106;
(g) R. Jackstell, H. Klein, M. Beller, K.-D. Wiese, D. Rottger,
Eur. J. Org. Chem. 20 (2001) 3871.
[7] J.D. Unruh, J.R. Christenson, J. Mol. Catal. 14 (1982) 19.
[8] W.R. Moser, C.J. Papile, D.A. Brannon, R.A. Duwell, J. Mol.
Catal. 41 (1987) 271.
Crystallography was performed using a Bruker
SMART diffractometer; full hemisphere of data with
0.3° ÔslicesÕ, room temperature, Mo Ka radiation and
empirical absorption corrections. All of the non-H atoms
were refined anisotropically with the hydrogen atoms
being refined in idealised geometries. All calculations
employed the SHELXTL program system [38].
[9] L.A. van der Veen, P.C.J. Kamer, P.W.N.M. van Leeuwen,
Organometallics 18 (1999) 4765.
[10] D.J. Wink, T.J. Kwok, A. Yee, Inorg. Chem. 29 (1990) 5006.
[11] E. Billing, A.G. Abatjoglou, D.R. Bryant, U.S. Patent 4,668,651,
European Patent Application 213,639, 1987 (to Union Carbide),
Chem. Abstr., 107 (1987) 7392.
[12] E. Billing, A.G. Abatjoglou, D.R. Bryant, R.E. Murray, J.M.
Maher, U.S. Patent 4,599,206, 1986 (to Union Carbide), Chem.
Abstr., 109 (1988) 233177.
[13] M. Rodriguez i Zubiri, M.L. Clarke, D.F. Foster, D.J. Cole-
Hamilton, A.M.Z. Slawin, J.D. Woollins, J. Chem. Soc., Dalton
Trans. (2001) 969.
4. Supplementary materials
[14] M. Rodriguez i Zubiri, A.M.Z. Slawin, M. Wainwright, J.D.
Woollins, Polyhedron 21 (2002) 1729.
Crystallographic data for the structural analyses has
been deposited with the Cambridge Crystallographic
data centre, CCDC Nos. 221581–221584 Copies of this
information may be obtained free of charge from The
Director CCDC, 12 Union Road, Cambridge, CB2 1EZ
UK (Fax +44 1223 336-033 or E-mail deposit@
ccdc.cam.ac.uk or www: http://www.ccdc.cam.ac.uk).
[15] M.L. Clarke, A.M.Z. Slawin, M.V. Wheatley, J.D. Woollins, JCS
Dalton (2001) 3421.
[16] S.M. Aucott, A.M.Z. Slawin, J.D. Woollins, JCS Dalton (2001)
2279.
[17] M. Wainwright, J.D. Woollins, JCS Dalton (2001) 2724.
[18] M.L. Clarke, D.J. Cole-Hamilton, J.D. Woollins, JCS Dalton
(2001) 2721.
[19] M.L. Clarke, G. Holliday, A.M.Z. Slawin, J.D. Woollins, JCS
Dalton (2002) 1093.
[20] Q. Zhang, S.M. Aucott, A.M.Z. Slawin, J.D. Woollins, Eur. J.
Inorg. Chem., Cover (2002) 1635.
Acknowledgements
[21] M.L. Clarke, A.M.Z. Slawin, J.D. Woollins, Polyhedron 22 (2003)
22.
We are grateful to the EPSRC for support, to John-
son Matthey for loans of precious metals and to the
JREI for an equipment grant.
[22] Q. Zhang, G. Hua, P. Bhattacharyya, A.M.Z. Slawin, J.D.
Woollins, Eur. J. Inorg. Chem. (2003) 2426.

M.R.I. Zubiri et al. / Polyhedron 23 (2004) 693–699
699
[23] N.C. Payne, D.W. Stephan, J. Organomet. Chem. 221 (1981)
203.
[31] P.A.W. Dean, Can. J. Chem. 57 (1979) 754.
[32] P.W. Dyer, J. Fawcett, M.J. Hanton, R.D.W. Kemmitt, R. Padda,
N. Singh, Dalton Trans. (2003) 104.
[24] M.S. Balakrishna, R.M. Abhyankar, J.T. Mague, J. Chem. Soc.,
Dalton Trans. (1999) 1407.
[33] N.G. Anderson, B.A. Keay, Chem. Rev. 101 (2001) 997.
[34] C.P. Casey, G.T. Whiteker, M.G. Melville, L.M. Petrovich, J.A.
Gavney Jr., D.R. Powell, J. Am. Chem. Soc 114 (1992) 5535.
[35] P.C.J. Kamer, P.W.N.M. van Leeuwen, J.N.H. Reek, Acc. Chem.
Res. 34 (2001) 895, and references therein.
[25] S. Miyano, M. Nawa, H. Hashimoto, Chem. Lett. (1980) 729.
[26] S. Miyano, M. Nawa, A. Mori, H. Hashimoto, Bull. Chem. Soc.
Jpn. 57 (1984) 2171.
[27] P. Bhattacharyya, A.M.Z. Slawin, M.B. Smith, D.J. Williams,
J.D. Woollins, J. Chem. Soc., Dalton Trans. (1996) 3647.
[28] A. Sen, Acc. Chem. Res. 26 (1993) 303.
[36] M. Rodriguez i Zubiri, PhD Thesis, University of St. Andrews,
2002.
[29] V.S. Reddy, K.V. Katti, C.L. Barnes, Chem. Ber. 127 (1994) 1355.
[30] P. Bhattacharyya, J. Novosad, J. Phillips, A.M.Z. Slawin, D.J.
Williams, J.D. Woollins, J. Chem. Soc., Dalton Trans. (1995) 1607.
[37] S.C. van der Slot, J. Duran, J. Luten, P.C.J. Kamer, P.W.N.M.
van Leeuwen, Organometallics 21 (2002) 3873.
[38] SHELXTL, Bruker AXS, Madison, WI, 1999.