A comparison of the ligating properties of the mixed P/O- and P/S-donor ligands and 7 carbonyls

Article abstract of DOI:10.1016/S0022-328X(02)01413-4

[M(CO)₄(nbd)] (M = Cr or Mo) react with L¹ (Ph₂P(CH₂)₂O(CH₂) ₂O(CH₂)₂PPh₂) to give the trans-[Cr(CO)₄(L¹)] and cis- [Mo(CO)₄ (L¹)] respectively, both of which show coordination of L¹ through the P atoms only, giving 11-membered ring metallocyclic complexes. The crystal structure of [Mo(CO)₄ (L¹)] confirms the cis-geometry of the product. The cis-[W(CO) ₄(L¹)] is obtained similarly from [W(CO) ₄(TMPA)]. Prolonged reaction of [MnCl(CO)₅] with L¹ affords mer-trans-[MnCl(CO)₃ (L¹)], with L¹ functioning as a trans chelate via the phosphine functions. The kinetic product fac-[MnCl(CO)₃ (L¹)] is obtained when short reaction times are used. In contrast, [ReBr(CO)₅] reacts with L¹ to give [ReBr(CO)₃(L¹)] as a mixture of geometric isomers. Both 1:1 and 2:1 M:L² (L² = Ph ₂P (CH₂)₂S(CH₂)₂ S(CH₂)₂PPh₂) may be obtained for M = Mn(I) or Mo(0). The [MnCl(CO)₃(L²)] exists in solution as the fac isomer with L² functioning as a bidentate P,S-donor ligand giving a five-membered chelate ring and with the remaining thioether and phosphine functions uncoordinated. Addition of a further equivalent of [MnCl(CO)₅] affords the binuclear fac-[{MnCl(CO)₃}₂(μ²-L²)], with symmetrical P,S-chelation to each metal centre. Similar behaviour is seen for Mo, thus cis-[{Mo(CO)₄}₂ (μ²-L²)] involves P,S-chelation to each Mo(0) ion. The related 1:1 species cis-[Mo(CO)₄(L²)] exists as a mixture of two compounds each with bidentate L² coordination, the P₂-chelate (11-membered ring metallocycle) and P,S-coordinated (five-membered chelate ring) species. The new compounds are characterised by microanalyses, IR, ¹H-, ¹³C{¹H}-, ³¹P{¹H}-, ⁵⁵Mn-NMR spectroscopy and mass spectrometry as appropriate. The different ligating properties of the related compounds L¹ and L² are discussed.

Full text of DOI:10.1016/S0022-328X(02)01413-4

Journal of Organometallic Chemistry 655 (2002) 55ꢁ62
/
www.elsevier.com/locate/jorganchem
A comparison of the ligating properties of the mixed P/O- and P/S-
donor ligands Ph2P(CH2)2O(CH2)2O(CH2)2PPh2 and
Ph2P(CH2)2S(CH2)2S(CH2)2PPh2 with Group 6 and 7 carbonyls
Bjorn Heuer, Melissa L. Matthews, Gillian Reid *, Mark Ripley
Department of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK
Received 14 February 2002; accepted 20 March 2002
Abstract
[M(CO)4(nbd)] (Mꢀ
Cr or Mo) react with L1 (Ph2P(CH2)2O(CH2)2O(CH2)2PPh2) to give the trans-[Cr(CO)4(L1)] and cis-
/
[Mo(CO)4(L1)] respectively, both of which show coordination of L1 through the P atoms only, giving 11-membered ring
metallocyclic complexes. The crystal structure of [Mo(CO)4(L1)] confirms the cis-geometry of the product. The cis-[W(CO)4(L1)] is
obtained similarly from [W(CO)4(TMPA)]. Prolonged reaction of [MnCl(CO)5] with L1 affords mer-trans-[MnCl(CO)3(L1)], with L1
functioning as a trans chelate via the phosphine functions. The kinetic product fac-[MnCl(CO)3(L1)] is obtained when short reaction
times are used. In contrast, [ReBr(CO)5] reacts with L1 to give [ReBr(CO)3(L1)] as a mixture of geometric isomers. Both 1:1 and 2:1
M:L2 (L2ꢀ
/
Ph2P(CH2)2S(CH2)2S(CH2)2PPh2) may be obtained for Mꢀ
Mn(I) or Mo(0). The [MnCl(CO)3(L2)] exists in solution as
/
the fac isomer with L2 functioning as a bidentate P,S-donor ligand giving a five-membered chelate ring and with the remaining
thioether and phosphine functions uncoordinated. Addition of a further equivalent of [MnCl(CO)5] affords the binuclear fac-
[{MnCl(CO)3}2(m2-L2)], with symmetrical P,S-chelation to each metal centre. Similar behaviour is seen for Mo, thus cis-
[{Mo(CO)4}2(m2-L2)] involves P,S-chelation to each Mo(0) ion. The related 1:1 species cis-[Mo(CO)4(L2)] exists as a mixture of two
compounds each with bidentate L2 coordination, the P2-chelate (11-membered ring metallocycle) and P,S-coordinated (five-
membered chelate ring) species. The new compounds are characterised by microanalyses, IR, 1H-, 13C{1H}-, 31P{1H}-, 55Mn-NMR
spectroscopy and mass spectrometry as appropriate. The different ligating properties of the related compounds L1 and L2 are
discussed. # 2002 Elsevier Science B.V. All rights reserved.
Keywords: P/O- and P/S-donor ligands; NMR spectroscopy; X-ray crystallography; Transition metal carbonyl complexes
1. Introduction
[Pt(OH2){Ph2P(CH2CH2O)4CH2CH2PPh2}]2ꢂ shows
Pt(II) coordinated to both phosphine functions,
one water molecule and to one of the ether oxygens
of the mixed P/O-donor ligand [7], while halogen
Interest in mixed phospha-thia and phospha-oxa
ligands stems from their ability to bond to a wide range
of metal ions, and the presence of the two different
donor atom types leads to considerable coordinative
flexibility for these ligands. In the ligands which we
oxidation of the square planar [Pt(L2)](PF6)2 (L2ꢀ
Ph2P(CH2)2S(CH2)2S(CH2)2PPh2) gives the unusual
Cl or Br) with
/
Pt(IV) species, [PtX2(L2)](PF6)2 (Xꢀ
/
retention of the tetradentate L2 coordination [2]. Alter-
natively, the thioether/ether groups may act as spacers
between the phosphines as, for example, in [Au(L)]PF6
have been studying [1ꢁ6], the phosphine functions
/
(good s-donors) are specifically introduced at
the termini to encourage coordination via the (soft)
thioether or (hard) ether functions (both of which
are much more modest s-donors). For example,
the crystal structure of the unusual Pt(II) species
(Lꢀ
L1 or L2) [1,3,4] and [NiI2(L1)] [8] in which L2
/
behaves as a trans chelate via the P-functions, or
[Au2(L2)2]Cl2 in which each Au(I) centre is coordinated
to two phosphine functions from the bridging ligands,
giving a helical metallocyclic structure with one of the
Clꢃ anions occupying the cavity [1].
* Corresponding author. Fax: ꢂ
E-mail address: gr@soton.ac.uk (G. Reid).
/44-023-80593781
0022-328X/02/$ - see front matter # 2002 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 2 - 3 2 8 X ( 0 2 ) 0 1 4 1 3 - 4

56
B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ62
/
Few studies have been conducted on transition metal
consistent with [Mo(CO)2(L1)]ꢂ and [Mo(CO)(L1)]ꢂ
or [W(CO)2(L1)]ꢂ and [W(L1)]ꢂ, the mass spectrum of
the chromium species gave no useful information. These
data and 1H-NMR spectroscopic data are consistent
with the formulation [Mo(CO)4(L1)] or [W(CO)4(L1)]
for the products. The solution IR spectrum (CH2Cl2) of
the Mo product shows four peaks associated with
n(CO), consistent with retention of the cis-tetracarbonyl
carbonyl systems involving these or related ligands,
although Gray and co-workers have investigated in
detail the coordination of various P2Ox-donor ligands
(xꢀ
/
3ꢁ5) with molybdenum carbonyl to give cis-
/
[Mo(CO)4(L)] and have shown that the resulting metal-
locyclic cavities can in certain cases host alkali metal
ions. They have also shown that under UV irradiation
or in the presence of HgCl2 these Mo(0) species
isomerise to the corresponding trans isomers [9,10].
In this paper we describe the preparation and
characterisation of a series of new Group 6 and 7 metal
carbonyl complexes incorporating the mixed P/O- and
P/S-donor ligands L1 and L2, including the crystal
structure of [Mo(CO)4(L1)], which illustrate the quite
different ligating properties of L1 and L2.
arrangement (C2v, theory: 2a1ꢂ
/
b1ꢂb2). For the tung-
/
sten complex only three bands are seen, probably due to
accidental coincidence of two peaks at 1883 cmꢃ1. Cis-
[Mo(CO)4{Ph2P(CH2CH2O)3CH2CH2PPh2}] [9] shows
n(CO) at 2022, 1920, 1905 and 1885 cmꢃ1. The
13C{1H}-NMR spectra of the Mo and W complexes of
L1 each show resonances associated with coordinated
L1, together with a (poorly resolved) triplet and doublet
of doublets due to CO trans CO and CO trans P,
respectively. However, the 13C{1H}-NMR spectrum of
the Cr species shows only one poorly resolved triplet in
the CO region, while the IR spectrum shows a single,
strong n(CO) absorption at 1877 cmꢃ1, both of which
are indicative of the presence of only the trans-
[Cr(CO)4(L1)] isomer. The 31P{1H}-NMR spectrum of
2. Results and discussion
2.1. Complexes of L1
A summary of the products obtained from reaction of
various Group 6 and 7 carbonyl species with L1 is given
in Scheme 1.
this Cr(0) compound shows a singlet at ꢂ56.5 ppm. The
/
ready formation of the trans isomer under these mild
reaction conditions contrasts with the report from Gray
and co-workers for related molybdenum species where
UV irradiation or HgCl2 catalysis are required to
Treatment of cis-[M(CO)4(nbd)] (Mꢀ
cis-[W(CO)4(TMPA)] (nbdꢀ2,5-norbornadieneꢀ
clo[2.2.1]-hepta-2,5-diene; TMPAꢀN,N,N?,N?-tetra-
/Cr or Mo) or
/
/bicy-
/
methyl-propylendiamine) with L1 in a 1:1 molar ratio
in toluene (or chloroform for W) gave yellow solutions.
The reactions were monitored by solution IR spectro-
scopy, until the n(CO) absorptions due to the starting
material had disappeared. The products were isolated by
evaporation to dryness, dissolution in CH2Cl2 and
precipitation with hexane. While the electrospray mass
(MeCN) spectra of the Mo and W complexes showed
clusters of peaks with the correct isotopic patterns
convert the cis-[Mo(CO)4(L)] (LꢀP2Ox-donor ligands)
/
into the corresponding trans species [10]. We also note
that a 31P{1H}-NMR spectrum of the reaction mixture
at an earlier stage in the reaction showed a further
singlet at d 28.8 (together with a resonance correspond-
ing to ‘free’ L1 and the ꢂ
56.5 ppm resonance associated
/
with the trans isomer above) which we tentatively assign
to an intermediate cis isomer involving P2-coordination
from L1.
Scheme 1. Complexes of L1 (L1ꢀ
/
Ph2P(CH2)2O(CH2)2O(CH2)2PPh2).

B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ
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57
The 31P{1H}-NMR spectra of the cis-[Mo(CO)4(L1)]
and cis-[W(CO)4(L1)] each show a singlet at 17.8 and 3.9
ppm, respectively with 183W satellites on the latter
Table 1
1
˚
Selected bond lengths (A) and angles (8) for cis-[Mo(CO)4(L )]
Bond lengths
(1J(183Wꢁ31
6 element is as expected, and the resonances are all to
high frequency of L1 itself (ꢃ21 ppm), indicative of k2-
/
P) 225 Hz). This trend in d(31P) with Group
Mo(1)ꢀP(1)
Mo(1)ꢀP(2)
Mo(1)ꢀC(31)
Mo(1)ꢀC(32)
Mo(1)ꢀC(33)
Mo(1)ꢀC(34)
2.539(1)
2.573(1)
2.041(5)
1.982(5)
2.033(5)
2.004(5)
/
coordination through P, although the shifts are not
sufficiently high to suggest that the phosphines are part
of a five-membered chelate ring [11].
The crystal structure of [Mo(CO)4(L1)] confirms (Fig.
1, Table 1) that L1 acts as a cis-chelate to Mo via the
two P-donor atoms at the termini, with four CO ligands
completing the distorted octahedral coordination at
Bond angles
P(1)ꢀMo(1)ꢀP(2)
P(1)ꢀMo(1)ꢀC(32)
P(1)ꢀMo(1)ꢀC(34)
P(2)ꢀMo(1)ꢀC(32)
P(2)ꢀMo(1)ꢀC(34)
C(31)ꢀMo(1)ꢀC(33)
C(32)ꢀMo(1)ꢀC(33)
C(33)ꢀMo(1)ꢀC(34)
95.41(4) P(1)ꢀMo(1)ꢀC(31)
95.6(1)
86.7(1)
169.7(1)
176.7(1)
92.6(1)
174.5(2)
85.9(2)
84.9(2)
P(1)ꢀMo(1)ꢀC(33)
P(2)ꢀMo(1)ꢀC(31)
P(2)ꢀMo(1)ꢀC(33)
C(31)ꢀMo(1)ꢀC(32)
C(31)ꢀMo(1)ꢀC(34)
C(32)ꢀMo(1)ꢀC(34)
88.4(1)
91.9(1)
91.5(1)
90.5(2)
90.7(2)
85.1(2)
Mo(0). The Pꢀ
/
Moꢀ
/
P angle within the large 11-mem-
bered metallocyclic ring is 95.41(4)8, with the O-atoms
remaining uncoordinated. This structure is similar to
that reported by Gray and co-workers for cis-
[Mo(CO)4{Ph2P((CH2)2O)3(CH2)2PPh2}] which shows
˚
P bond lengths of 2.5444(7), 2.5608(7) A and
reaction was monitored by solution IR, until the peaks
due to the starting material disappeared completely, by
which stage they had been replaced by peaks at 2095,
2026, 2010 and 1958 cmꢃ1. The appearance of four
n(CO) bands of different intensities suggested the
presence of more than one geometric isomer. Several
isomeric forms are possible for [MnCl(CO)3(k2-L1)],
however, if we consider only P-coordination (coordina-
tion to the soft Mn(I) centre via the ether functions is
Moꢀ
Moꢀ
[9]. The Pꢀ
/
˚
2.036(3) A
/
C bond lengths in the range 1.976(3)ꢁ
/
/
MoꢀP angle in this larger ring metallocyclic
/
compound is smaller (93.78(2)8) than in cis-
[Mo(CO)4(L1)].
For the Group 7 carbonyl complexes we employed
[MnCl(CO)5] and [ReBr(CO)5] as the precursors, both
of which readily undergo substitution of two CO ligands
on addition of e.g. a diphosphine. In a preliminary
reaction [MnCl(CO)5] was treated with L1 in a 1:1 molar
ratio in chloroform to give a yellow solution. The
unlikely and does not occur*see below) the possibilities
/
are fac, mer-cis and mer-trans, each of which should
lead to three CO stretching vibrations, although the
intensities and positions of the bands are expected to
vary. In the solid state IR spectrum (CsI) five bands
were observed in the CO region, attributed (on the basis
of these data and the NMR data) to the presence of a
mixture of the fac and the mer-trans isomers*see
/
below. The electrospray mass spectrum showed peaks
corresponding to [Mn(CO)3(L1)]ꢂ as well as several
fragment ions at lower m/z, due to loss of CO. The
31P{1H}-NMR spectrum of this product showed two
resonances at 44.0 and 29.9 ppm of different intensities.
Repeating the reaction with refluxing for a longer period
(18 h) gave a yellow solid. The IR spectrum of this
product shows three n(CO) bands at 2045, 1949 and
1909 cmꢃ1, while the 31P{1H}-NMR spectrum shows
only one resonance at 44 ppm. The presence of only one
resonance eliminates the mer-cis isomer and this,
together with the IR data suggest that the product
isolated under these conditions is the mer-trans isomer.
In this species L1 is therefore behaving as a trans chelate
through the phosphine units. The 13C{1H}-NMR spec-
trum shows resonances associated with coordinated L1
as well as d(CO) at 212 ppm which is broadened
significantly by the directly bonded 55Mn quadrupolar
nucleus and therefore the different CO environments are
poorly resolved. Similar observations have been made
Fig. 1. View of the structure of cis-[Mo(CO)4(L1)] with numbering
scheme adopted. Ellipsoids are drawn at 40% probability. H atoms are
omitted for clarity.

58
B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ62
/
for other Mn(I) carbonyl complexes with phosphine co-
ligands [12]. The 55Mn-NMR spectrum shows a very
appear to be cis-tetracarbonyl species. The 31P{1H}-
NMR spectrum of this mixture shows three singlet
broad resonance at ꢃ
/
1300 ppm (w1/2
ꢀ
/
19,000 Hz),
resonances; a 1:1 pair at 52.9 and ꢃ16.6 ppm associated
/
consistent with coordination of L1 to the Mn(I) centre
via the phosphines only, giving mer-trans-
[MnCl(CO)3(L1)]. The low symmetry of this isomer
leads to the very large line-width.
with a bidentate P,S chelated L2 on Mo (the resonance
at 52.9 ppm corresponds to a coordination shift
(dcomplex
ꢃ
/
dfree ligand) of ꢂ68 ppm, strongly suggesting
/
that the P atom is contained within a five-membered
chelate ring [11], whereas the low frequency resonance is
very close to ‘free’ L2, suggesting that this P centre is
uncoordinated in the complex) and a third resonance at
26.1 ppm, which is of higher intensity and is attributed
to a complex involving P2-coordination by L2. The
13C{1H}-NMR spectrum of this mixture is complex,
however, the CO region is clearly consistent with the
assignment of the products as cis-tetracarbonyl Mo(0)
complexes, one of which shows P,S-chelation (three
doublets in a 1:1:2 ratio) and the other of which shows
P2-chelation of L2 (doublet of doublets and triplet).
A similar reaction of L2 with 2 M equivalents of
[Mo(CO)4(nbd)] leads to the formation of a single
species assigned as cis-[{Mo(CO)4}2(m2-L2)] (IR
Repeating this reaction at room temperature with
stirring for only ca. 2 h results in incomplete consump-
tion of the [MnCl(CO)5] precursor, however, IR and
NMR spectroscopic studies indicate that the major
product is the fac-[MnCl(CO)3(L1)] with P2-coordina-
tion of L1 (d31P 29.9). The n(CO) bands at 2027, 1957,
1910 cmꢃ1 are in accord with those in other fac-
[MnCl(CO)3(diphosphine)] compounds [12]. It is inter-
esting to note the ease with which this complex under-
goes isomerisation to the mer-trans form compared to
species such as fac-[MnCl(CO)3(L)2], LꢀPPh2H or
/
PPhH2. In the case of [MnCl(CO)3(L1)] this isomerisa-
tion may relieve strain in the large 11-membered chelate
ring present in the fac isomer.
We also obtained [ReBr(CO)3(L1)] in good yield,
although even after 24 h at reflux in CHCl3, the IR
spectrum shows bands associated with both fac and mer
species and the 31P-NMR spectrum shows the presence
n(CO)ꢀ
2024, 1919, 1910sh, 1872 cmꢃ1). The
/
31P{1H}-NMR spectrum of this product reveals only
one singlet at 53.0 ppm, very similar to the chemical
shift for the P,S-chelate complex in the 1:1 Moꢁ
L2
/
of two resonances of unequal intensities at ꢃ
/12.9 and
species above. As expected, the 13C{1H}-NMR spec-
trum of this species shows three doublet CO resonances
corresponding to CO trans S, CO trans P and CO trans
CO. The CH2 region of the spectrum is also consistent
with symmetrical coordination of L2, giving three CH2
environments.
ꢃ
/
13.5 ppm. These data suggest that two isomers are
present, probably fac and mer-trans like in the Mn(I)
system above. Varying the reaction time leads to
changes in the relative quantities of the two species,
but prolonged reflux (intended to encourage formation
of the mer-trans species) led to decomposition, while
short reaction times (intended to favour the fac isomer)
gave a significant amount of unreacted [ReBr(CO)5] and
still showed a mixture of isomers. This behaviour is
consistent with the low spin Re(I) ion being much more
Reaction of [MnCl(CO)5] with 1 M equivalent of L2
in CH2Cl2 gives a yellow solid. IR spectrum shows three
strong CO stretching vibrations associated with the fac
isomer. The 31P-NMR spectrum of this species shows
two resonances of equal intensity at 70.0 and ꢃ
ppm. The low frequency resonance is essentially un-
shifted from L2 itself (ꢃ
16 ppm), while the high
/16.6
inert to substitution than the corresponding Mn(I)*the
/
need for long reaction times and refluxing solvent to
effect substitution also promotes some isomerisation.
The mass spectrum of the solid isolated shows clusters
of peaks with the correct isotope pattern for
[Re(CO)3(L1)]ꢂ and fragments corresponding to succes-
sive loss of CO.
/
frequency resonance corresponds to a coordination shift
of 86 ppm, strongly suggesting that this P centre is part
of a five-membered chelate ring [11]. Thus, these data
suggest that L2 coordinates to Mn(I) via chelation
through one P atom and an adjacent S atom. The other
P and S atoms remain uncoordinated. The 1H- and
13C{1H}-NMR spectra are also consistent with this
assignment, both of which show more resonances than
expected for a symmetrically bound L2. The 55Mn-
NMR spectrum reveals a very broad resonance at
Microanalytical data suggest that the isolated com-
plexes of L1 (and L2 below) have a tendency to associate
1
solvent and there is evidence for CH2Cl2 in the H- (5.3
ppm) and 13C{1H}-NMR spectra (54.1 ppm) of the
complexes even after drying in vacuo.
ca. ꢃ
shifts for fac-[MnCl(CO)3{MeS(CH2)2SMe}] and fac-
Ph2P(CH2)2PPh2) and con-
sistent with P,S-chelation by L2 at Mn(I) [12,13].
Reaction of L2 with 2 M equivalents of [MnCl(CO)5]
leads to the binuclear species fac-[{MnCl(CO)3}2(m2-
L2)] in which L2 functions as a bidentate (P,S) chelate to
each Mn(I) centre. This is confirmed by microanalyses
/
700 ppm, intermediate between the chemical
2.2. Complexes of L2
[MnCl(CO)3(dppe)] (dppeꢀ
/
The products obtained from reaction of Mn(I) and
Mo(0) carbonyls with L2 are illustrated in Scheme 2.
[Mo(CO)4(nbd)] reacts with 1 M equivalent of L2 in
CH2Cl2 to give a mixture of two products which, on the
basis of IR and 13C{1H}-NMR spectroscopy, both

B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ
/62
59
Scheme 2. Complexes of L2 (L2ꢀ
Ph2P(CH2)2S(CH2)2S(CH2)2PPh2).
/
and spectroscopic studies. The IR spectrum shows three
strong n(CO) bands (2033, 1958, 1921 cmꢃ1), consistent
with the fac-tricarbonyl unit, while the 31P-NMR
spectrum of this compound shows a single resonance
In contrast, L2 readily forms both mono- and di-
nuclear complexes with Mn(I) and Mo(0). This is
because both the phosphines and the thioethers can
coordinate to the metal ion. Thus, the 1:1 Mnꢁ
L2
species exists as a five-membered ring P,S-chelate
/
at 70.6 ppm. As in the case for the 1:1 Mnꢁ
L2 complex
/
complex (with the other S and P atoms uncoordinated),
while the 1:1 Moꢁ
L2 species occurs as a mixture of the
above, the coordination shift of 86.6 ppm here is
significantly greater than for fac-[MnCl(CO)3(L1)]
above (50 ppm) which has no five-membered chelate
ring. No resonance was observed by 55Mn-NMR for this
compound, possibly due to slow tumbling of the large
dimer molecules.
/
11-membered ring P2-chelate complex (with the
thioethers uncoordinated) and the five-membered ring
P,S-chelate. Formation of the P,S-chelate complexes
with L2 may be accounted for by the availability of the
soft thioethers (compared to the hard ethers in L1 which
are not compatible with the soft metal ions) adjacent to
the phosphines, both of which are suitable for coordina-
tion to the low valent metal centres, together with the
extra stability associated with the five-membered chelate
ring. Addition of a further equivalent of the metal
precursor then gives the binuclear species cis-
[{Mo(CO)4}2(m2-L2)] and fac-[{MnCl(CO)3}2(m2-L2),
each of which contain two five-membered chelate rings
from P,S coordination to each metal centre.
2.3. Comparisons and conclusions
These results show that a range of carbonyl complexes
involving Group 6 and 7 elements may be obtained
upon reaction with the related P2O2- and P2S2-donor
ligands L1 or L2. While all of the complexes isolated
involve phosphine coordination, the structures of the
products are very dependent on the nature of the other
donor atoms present in the ligand.
For L1 we have obtained a new series of mononuclear
products with coordination of L1 occurring through the
phosphine functions. In the low valent complexes the
ethers essentially act as spacers, thus L1 behaves as a
long chain diphosphine ligand. With the 3d metals,
Cr(0) and Mn(I), the thermodynamic products appear
to be the trans (or mer-trans for Mn(I)) isomers. This
illustrates the propensity for L1 to function as a trans
chelate and is consistent with earlier observations on a
variety of other transition metal complexes e.g. with
Ni(II) [8], Ag(I) and Au(I) [4,6] where trans L1
coordination also occurs. With Mo(0) and W(0) cis
P2-coordination of L1 is observed, giving rise to 11-
membered ring metallocyclic products. These species
probably represent kinetic products.
3. Experimental
Infrared spectra were recorded in CH2Cl2 solution
using a Perkinꢁ
/
Elmer 1710 FTIR over the range 2200ꢁ
/
1700 cmꢃ1 or as CsI discs over the range 4000ꢁ
/
200
cmꢃ1. Mass spectra were run by fast-atom bombard-
ment (FAB) using 3-NOBA (3-nitrobenzyl alcohol)
matrix on a VG Analytical 70-250-SE Normal Geome-
try Double Focusing Mass Spectrometer or by electro-
spray or atmospheric pressure chemical ionisation
(APCI) in MeCN solution using a VG Biotech platform.
1H-NMR spectra were recorded in CDCl3 using a
Bruker AM300 spectrometer. 31P{1H}-, 13C{1H}- and
55Mn-NMR spectra were recorded in CH2Cl2 contain-

60
B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ62
/
ing ca. 10ꢁ
/
15% CDCl3 using a Bruker DPX400 spectro-
meter operating at 161.98, 100.63 or 99.09 MHz,
3.1.3. cis-[W(CO)4(L1)]
To a solution of L1 (0.100 g, 0.206 mmol) in degassed
CHCl3 (25 cm3) was added [W(CO)4(TMPA)] (0.089 g,
0.206 mmol). The resulting mixture was refluxed for 5 h
and then concentrated in vacuo to ca. 5 cm3. Hexane
(ca. 30 cm3) was added to afford a brown solid, which
was filtered, washed with C6H14 and dried in vacuo.
respectively and are referenced to external 85% H3PO4,
Me4Si or aqueous KMnO4 (dꢀ0). [Cr(acac)3] was
/
added to the NMR solutions prior to recording
13C{1H}-NMR spectra and a pulse delay of 2 s. was
introduced to accommodate the long relaxation times.
Microanalyses were obtained from the University of
Strathclyde microanalytical service.
The ligands L1 and L2 were prepared by literature
methods [4,14,15].
Yield: 73%. Calc. for [C34H32O6P2W]×
H, 3.8. Found: C, 45.7; H, 5.1%. APCI mass spectrum
(MeCN): Found: m/zꢀ726, 669; Calc. for
183W(CO)2(L1)]ꢂ m/zꢀ725, [183W((L1)]ꢂ m/zꢀ
669.
/
2CH2Cl2: C, 45.4;
/
[
/
/
1H-NMR: d 7.3ꢁ
7.7 (m, Ph, 20H), 3.6 (m, CH2O, 4H),
/
3.5 (s, CH2O, 4H), 2.6 (m, CH2P, 4H). 31P{1H}-NMR:
d 3.9 (s, L1, JWP
1
3.1. Preparations
ꢀ
232 Hz). 13C{1H}-NMR: 205.7 (t,
/
CO trans CO), 203.5 (dd, CO trans P), 127.7ꢁ139.4
/
(Ph), 71.1 (CH2O), 67.5 (CH2O), 32.8 (CH2P). n(CO)
(CH2Cl2, cmꢃ1): 2017s, 1916s, 1883sbr. n(CO) (CsI
disk, cmꢃ1): 2013s, 1905sh, 1883brs.
3.1.1. trans-[Cr(CO)4(L1)]
To a degassed solution of L1 (0.100 g, 0.206 mmol) in
C6H5CH3 (30 cm3) was added [Cr(CO)4(nbd)] (0.057 g,
0.206 mmol). The resulting solution was stirred at 40 8C
for 48 h. The solution was then concentrated in vacuo to
ca. 5 cm3 and hexane (ca. 30 cm3) was added to afford a
pale yellow solid which was filtered, washed with C6H14
3.1.4. Mer-trans-[MnCl(CO)3(L1)]
To a solution of L1 (0.320 g, 0.65 mmol) in degassed
CHCl3 (50 cm3) in a foil-wrapped flask was added
[MnCl(CO)5] (0.150 g, 0.65 mmol). The reaction mixture
was refluxed under N2 for 48 h until the solution IR
spectrum showed that all of the [MnCl(CO)5] had been
consumed and that there were no further changes in the
n(CO) region. The solution was then concentrated in
vacuo to ca. 5 cm3, and this was then added to ice-cold
C6H14 to afford a bright yellow solid which was filtered,
washed with C6H14 and dried in vacuo. Yield: 0.27 g,
63%. Calc. for [C33H32ClMnO5P2]: C, 60.0; H, 4.9.
Found: C, 60.3; H, 4.7%. Electrospray mass spectrum
and dried in vacuo. Yield: 40%. 31P{1H}-NMR: d 56.5
1
(s, L1). H-NMR: d 7.1ꢁ
/
7.7 (m, Ph, 20H), 3.3ꢁ
2.9 (m, CH2P, 4H). 13C{1H}-NMR:
222.7 (poorly resolved t, CO), 128.7ꢁ141.2 (Ph), 70.8
/
3.5 (m,
CH2O, 8H), 2.7ꢁ
/
/
(CH2O), 67.1 (CH2O), 33.8 (CH2P). n(CO) (CH2Cl2,
cmꢃ1): 1877s. Repeated attempts to obtain satisfactory
microanalytical data for this compound showed low
%C, however, the compound has been spectroscopically
characterised.
(MeCN): Found m/zꢀ
[Mn(CO)3(L1)]ꢂ m/zꢀ
597, [Mn(CO)(L1)]ꢂ m/zꢀ
/
625, 597, 569, 541, 487; Calc. for
625, [Mn(CO)2(L1)]ꢂ m/zꢀ
569, [Mn(L1)]ꢂ m/zꢀ
541,
486. H-NMR: d 7.2ꢁ7.9 (br m, Ph, 20H),
/
/
3.1.2. cis-[Mo(CO)4(L1)]
/
/
[Mo(CO)4(nbd)] (0.062 g, 0.206 mmol) was added to a
degassed solution of L1 (0.100 g, 0.206 mmol) in CHCl3
(25 cm3). The reaction mixture was stirred at room
temperature (r.t.) for ca. 18 h until solution IR spectro-
scopy showed that all of the starting material had been
consumed. The solution was then evaporated to dryness
in vacuo and redissolved in CH2Cl2. Hexane was then
added to precipitate the product which was collected by
filtration, washed with hexane and dried in vacuo. Yield:
1
[L1]ꢂ m/zꢀ
/
/
3.4 (br m, CH2O, 4H), 3.3 (br s, CH2O, 4H), 2.9 (br m,
CH2P, 4H). 31P{1H}-NMR: d 44 (s, L1, mer-cis isomer).
55Mn-NMR: d ꢃ1300 (br, w1/2 ca. 19,000 Hz). 13C{1H}-
/
NMR: 211.7 (br, CO), 127.5ꢁ137.4 (Ph), 70.2 (CH2O),
/
66.4 (CH2O), 27.9 (CH2P). n(CO) (CH2Cl2, cmꢃ1):
2045m, 1949s, 1909m.
53%. Calc. for [C34H32MoO6P2]×
4.7. Found: C, 56.7; H, 4.8%. Electrospray mass
spectrum (MeCN): Found m/zꢀ641, 613, 487; Calc.
for [98Mo(CO)2(L1)]ꢂ m/zꢀ640, [98Mo(CO)(L1)]ꢂ m/
486. H-NMR: d 7.3ꢁ7.6 (m, Ph,
/
1/2CH2Cl2: C, 56.2; H,
3.1.5. Fac-[MnCl(CO)3(L1)]
Method as above, except that the reaction was stirred
at r.t. under N2 for 2 h. The solvent was removed in
vacuo and the residue was redissolved in CH2Cl2 and
added to ice-cold C6H14 to give a bright yellow solid.
/
/
1
zꢀ
/
612, [L1]ꢂ m/zꢀ
/
/
20H), 3.7 (m, CH2O, 4H), 3.5 (s, CH2O, 4H), 2.6 (m,
CH2P, 4H). 31P{1H}-NMR: d 17.8 (s, L1). 13C{1H}-
NMR: 215.8 (t, CO trans CO), 210.1 (dd, CO trans P),
Yield: 51%. Required for [C33H32ClMnO5P2]×
3CH2Cl2: C, 58.1; H, 4.8. Found: C, 58.0; H, 4.7%.
1H-NMR: 7.3ꢁ
7.7 (br m, Ph, 20H), 3.5 (br m, CH2O,
/
1/
/
128.7ꢁ
/
136.7 (Ph), 70.1 (CH2O), 67.2 (CH2O), 33.1
4H), 3.4 (br s, CH2O, 4H), 2.5 (br m, CH2P, 4H).
31P{1H}-NMR: 29.9 (s, L1, fac isomer, major), 44 (s, L1,
mer-trans isomer, minor). n(CO) (CH2Cl2, cmꢃ1):
2027s, 1957s, 1910s.
(CH2P). n(CO) (CH2Cl2, cmꢃ1): 2022s, 1924s, 1903s,
1885sh. n(CO) (CsI disk, cmꢃ1): 2020s, 1918s, 1903s,
1885sh.

B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ
/62
61
1
3.1.6. [ReBr(CO)3(L1)]
H, 3.6%. H-NMR: d 7.3ꢁ
/
7.7 (br m, Ph, 20H), 3.1 (s,
To a degassed solution of L1(0.100 g, 0.206 mmol) in
CHCl3 (30 cm3) was added [ReBr(CO)5] (0.08 g, 0.206
mmol). The resulting solution was refluxed for 24 h and
then concentrated to ca. 5 cm3 in vacuo. Ice-cold C6H14
(50 cm3) was then added to afford a cream/fawn solid
which was filtered, washed with C6H14 and dried in
SCH2CH2S, 4H), 2.9 (m, CH2, 4H), 2.5 (m, CH2, 4H).
31P{1H}-NMR: d 53.0 (s, L2). 13C{1H}-NMR: 217.3 (d,
7 Hz, COtrans S), 215.1 (d, 28 Hz, COtrans P), 206.9 (d, 9
Hz, COtrans CO), 134.8ꢁ128.0 (Ph), 39.2 (s, SCH2CH2S),
34.7 (d, 15 Hz, SCH2CH2P), 26.2 (d, 23 Hz, PCH2). IR
spectrum (CsI disc): 2033, 1950, 1921 cmꢃ1
/
.
vacuo. Yield: 23%. Calc. for [C33H32BrO5P2Re]×
3CHCl3: C, 44.1; H, 3.6. Found: C, 44.0; H, 4.0%.
FAB mass spectrum: Found m/zꢀ729, 727; Calc. for
187Re(CO)2(L1)]ꢂ m/zꢀ729, [185Re(CO)2(L1)]ꢂ m/zꢀ
727. 1H-NMR: d 7.3ꢁ
7.7 (br m, Ph, 20H), 3.5 (m,
CH2O, 4H), 3.4 (m, CH2O, 4H), 2.5 (m, CH2P, 4H).
31P{1H}-NMR: d ꢃ12.8 (s, L1), ꢃ13.4 (s, L1). IR
spectrum (CsI disc): 2108m, 2036s, 1950s, 1910brs
cmꢃ1
/
2/
3.1.10. [Mo(CO)4(L2)]
/
Method as above but using a 1:1 [Mo(CO)4(nbd)]ꢁ
L2
ratio. Fawn coloured solid. Yield: 57%. Calc. for
/
[
/
/
/
[C34H32MoO4P2S2]1/4CH2Cl2: C, 55.0; H, 4.4. Found:
1
C, 54.9; H, 4.6%. H-NMR: d 7.3ꢁ
/
7.7 (br m, Ph, 20H),
/
/
2.1ꢁ
/
2.7 (br m, CH2, 12H). 31P{1H}-NMR: d 26.2 (s,
52.9 (s, coordi-
16.6 (s, uncoordi-
coordinated PPh2 in P2-chelating L2), ꢂ
/
.
nated PPh2 in P,S-chelating L2), ꢃ
/
nated PPh2 on P,S-chelating L2). 13C{1H}-NMR: 217.5
(d, 7 Hz, COtrans S, P,S-chelate), 215.0 (d, 28 Hz, COtrans
in P,S chelate), 214.8 (poorly resolved dd, COtrans P in
3.1.7. [{MnCl(CO)3}2(m2-L2)]
To a degassed solution of L2 (0.200 g, 0.39 mmol) in
CH2Cl2 (30 cm3) in a foil-wrapped flask, was added
MnCl(CO)5 (0.180 g, 0.77 mmol). The resulting solution
was stirred for 4 h. The yellow solution was concen-
trated in vacuo to ca. 5 cm3 and C6H14 (50 cm3) was
then added, giving a yellow solid which was filtered,
washed with C6H14 and dried in vacuo. Yield: 61%.
P
P2 chelate), 209.0 (poorly resolved t, COtrans CO in P2-
chelate), 207.2 (d, 9 Hz, COtrans
in P,S chelate),
CO
136.2ꢁ
/
128.9 (Ph), 41.9ꢁ26.7 (CH2). IR spectrum
/
(CH2Cl2): 2022s, 1918 sh, 1908s, 1881s cmꢃ1
.
Calc. for [C36H32Cl2Mn2O6P2S2]×
/
1/2CH2Cl2: C, 48.2; H,
1
3.7. Found: C, 48.2; H, 4.0%. H-NMR: d 7.0ꢁ
m, Ph, 20H), 2.5ꢁ
3.4 (br m, CH2, 12H). 31P{1H}-NMR:
d 70.6 (s, L2). 13C{1H}-NMR: 221ꢁ
218 (br, CO),
/7.8 (br
4. X-Ray crystallography
/
/
Details of the crystallographic parameters are given in
Table 2. Crystals of [Mo(CO)4(L1)] were grown by
vapour diffusion of diethyl ether onto a solution of the
129.9ꢁ138.4 (Ph), 34.7, 31.9, 27.3 (CH2). IR spectrum
/
(CH2Cl2): 2033, 1950, 1921 cmꢃ1
.
complex in CH2Cl2 at ca. ꢃ15 8C. Data collection used
a Rigaku AFC7S four-circle diffractometer equipped
with an Oxford Systems open-flow cryostat operating at
/
3.1.8. [MnCl(CO)3(L2)]
As above but using a 1:1 ratio of MnCl(CO)5:L2.
Yellow
[C33H32ClMnO3P2S2]×
Found: C, 55.2; H, 4.7%. Electrospray mass spectrum
solid.
Yield:
59%.
Calc.
for
150 K, using graphite-monochromated Moꢁ
/
Ka X-
0.71073 A). Structure solution and refine-
˚
/
1/2CH2Cl2: C, 54.7; H, 4.5.
radiation (lꢀ
/
(MeCN): Found m/zꢀ
[Mn35Cl(CO)3(L2)]ꢂ m/zꢀ
zꢀ
7.8 (br m, Ph, 20H), 2.5ꢁ
NMR: d 70.9 (s, coordinated PPh2 on L2), ꢃ
uncoordinated PPh2 on L2). 13C{1H}-NMR: 222, 218,
216 (br, CO), 129.2ꢁ138.4 (Ph), 38.5ꢁ
23.0 (CH2). 55Mn-
/
693, 657, 629; Calc. for
Table 2
Crystallographic parameters
/
692, [Mn(CO)3(L2)]ꢂ m/
1
/
657, [Mn(CO)2(L2)]ꢂ m/zꢀ
/
629. H-NMR: d 7.1ꢁ
/
Complex
cis-[Mo(CO)4(L1)]
/
3.4 (br m, CH2, 12H). 31P{1H}-
16.6 (s,
Empirical formula
Formula weight
Crystal system
Space group
C34H32MoO6P2
694.51
/
Monoclinic
P21/n
/
/
NMR: ꢃ700 (w1/2 ca. 15,000 Hz). IR spectrum (CsI
/
˚
a (A)
15.776(4)
12.543(3)
16.296(3)
102.28(2)
3150(1)
4
disc): 2032, 1957, 1919 cmꢃ1
.
˚
b (A)
˚
c (A)
3.1.9. [{Mo(CO)4}2(L2)]
b (8)
3
U (A )
˚
To a degassed solution of L2 (0.100 g, 0.19 mmol) in
CH2Cl2 (30 cm3) was added [Mo(CO)4(nbd)] (0.120 g,
0.40 mmol). The resulting solution was stirred for 12 h.
The solution was then concentrated in vacuo to ca. 5
cm3 and C6H14 (30 cm3) was added to afford a fawn
coloured solid which was filtered, washed with C6H14
and dried in vacuo. Yield: 52%. Calc. for
[C38H32Mo2O8P2S2]: C, 48.8; H, 3.5. Found: C, 49.6;
Z
m(Moꢁ
/
Ka) (cmꢃ1
Unique observed reflections
)
5.47
5833
Observed reflections with [Ioꢀ2s(Io)]
R
Rw
3885
0.038
0.047
Rꢀa (jFobsjiꢃjFcalcji)/a jFobsji;
Rw ꢀ([a wi(½Fobs½i ꢃ½Fcalc½i)2=a wi½Fobs½2)1=2
:/
i

62
B. Heuer et al. / Journal of Organometallic Chemistry 655 (2002) 55ꢁ62
/
[3] A.R.J. Genge, A.M. Gibson, N.K. Guymer, G. Reid, J. Chem.
Soc. Dalton Trans. (1996) 4099.
ment were routine [16,17]. Selected bond lengths and
angles are given in Table 1.
[4] B. Heuer, S.J.A. Pope, G. Reid, Polyhedron 19 (2000)
743.
[5] C.L. Doel, A.M. Gibson, G. Reid, C.S. Frampton, Polyhedron 14
(1995) 3139.
5. Supplementary material
[6] F. Harrington, M.L. Matthews, B. Patel, G. Reid, Polyhedron 20
(2001) 2741.
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC no. 179097 for compound cis-
[Mo(CO)4(L1)]. Copies of this information may be
obtained free of charge from The Director, CCDC, 12
[7] A. Varshney, M.L. Webster, G.M. Gray, Inorg. Chem. 31 (1992)
2580.
[8] P. Dapporto, L. Sacconi, J. Chem. Soc. A (1971) 1914.
[9] A. Varshney, G.M. Gray, Inorg. Chem. 30 (1991) 1748.
[10] C.H. Duffey, C.H. Lake, G.M. Gray, Inorg. Chim. Acta 317
(2001) 199.
Union Road, Cambridge CB2 1EZ, UK (Fax: ꢂ44-
/
[11] P. Garrou, Chem. Rev. 8 (1981) 229.
[12] S.J.A. Pope, G. Reid, J. Chem. Soc. Dalton Trans. (1999)
1615.
1223-336033; e-mail: deposit@ccdc.cam.ac.uk or www:
http://www.ccdc.cam.ac.uk).
[13] J. Connolly, G. Goodban, G. Reid, A.M.Z. Slawin, J. Chem. Soc.
Dalton Trans. (1998) 2225.
[14] Y.-M. Hsiao, S.S. Chojnacki, P. Hinton, J.H. Reibenspies, M.Y.
Darensbourg, Organometallics 12 (1983) 870.
[15] N.R. Champness, R.J. Forder, C.S. Frampton, G. Reid, J. Chem.
Soc. Dalton Trans. (1996) 1261.
Acknowledgements
We thank the EPSRC for support.
[16] PATTY, The DIRDIF Program System, P.T. Beurskens, G.
Admiraal, G. Beurskens, W.P. Bosman, S. Garcia-Granda, R.O.
Gould, J.M.M. Smits, C. Smykalla, Technical Report of the
Crystallography Laboratory, University of Nijmegen, The Neth-
erlands, 1992.
References
[1] A.M. Gibson, G. Reid, J. Chem. Soc. Dalton Trans. (1996) 1267.
[2] J. Connolly, R.J. Forder, G. Reid, Inorg. Chim. Acta 264 (1997)
137.
[17] TEXSAN: Crystal Structure Analysis Package, Version 1.8, Mole-
cular Structure Corporation, Texas, 1997.