Aroylphosphanes: Base-Free Synthesis and Their Coordination Chemistry with Platinum-Group Metals

Article abstract of DOI:10.1002/ejic.201600592

A series of aroylphosphanes have been prepared in good yield by base-free condensation of the respective aroyl chloride and HPPh₂. Alongside the cyclophane m-{-C(O)-C₆H₄(C(O)PMe)}₂(1), the IR spectroscopic signatures of C₆H₄R{C(O)PPh₂} (R = 3-Me 2, 3-CH₂Cl 3, 4-CO₂Me 4, 4-CN 5) and the bis(aroylphosphanes) C₆H₄{2,6-C(O)PPh₂}₂(6) and C₆H₃N{2,6-C(O)PPh₂}₂(7) are consistent with a manifestation of “phosphomide” character; however, weight of evidence suggests negligible contribution from this canonical form. Comparison is drawn to the structurally characterised O=P(C₆H₅Me-2)₃(8) in which the lone pair is sequestered. The coordination of 2–5 to rhodium(I), palladium(II) and platinum(II) is described, affording rare examples of aroylphosphane complexes of the platinum-group metals.

Full text of DOI:10.1002/ejic.201600592

DOI: 10.1002/ejic.201600592
Full Paper
Phosphanes
Aroylphosphanes: Base-Free Synthesis and Their Coordination
Chemistry with Platinum-Group Metals
Amy J. Saunders,[a] Ian R. Crossley*[a] and S. Mark Roe[a]
Abstract: A series of aroylphosphanes have been prepared in “phosphomide” character; however, weight of evidence sug-
good yield by base-free condensation of the respective aroyl gests negligible contribution from this canonical form. Compar-
chloride and HPPh2. Alongside the cyclophane m-{-C(O)- ison is drawn to the structurally characterised O=P(C6H5Me-2)3
C6H4(C(O)PMe)}2 (1), the IR spectroscopic signatures of (8) in which the lone pair is sequestered. The coordination of
C6H4R{C(O)PPh2} (R = 3-Me 2, 3-CH2Cl 3, 4-CO2Me 4, 4-CN 5) 2–5 to rhodium(I), palladium(II) and platinum(II) is described,
and the bis(aroylphosphanes) C6H4{2,6-C(O)PPh2}2 (6) and affording rare examples of aroylphosphane complexes of the
C6H3N{2,6-C(O)PPh2}2 (7) are consistent with a manifestation of platinum-group metals.
Introduction
first-row metals. A limited range of group 9 complexes has been
described with “Cp′RhCl2” (Cp′ = Cp, Cp*)[6] and “Cp*IrCl2”[14]
Phosphorus ligands are a ubiquitous feature of modern organo-
metallic and coordination chemistry. The facility with which
their steric profiles and electronic properties (σ-basicity/π-acid-
ity) can be varied renders them a versatile means of controlling
metal reactivity, whether through the imposition of spectator
bulk, or direct modification of metal electron density. Conse-
quently, prolific levels of activity surround the synthesis and
development of phosphanes bearing a variety of functionalities
(alkyl, aryl, alkenyl, alkynyl, OR).[1] However, somewhat less stud-
ied are acylphosphanes, in which one or more carbonyl moie-
ties are directly bonded to a phosphorus atom. This relative
neglect has been attributed to inherent weakness of the P–
C(O) linkage,[2] which renders them prone to hydrolytic and/or
oxidative cleavage. Computational studies have suggested this
weakness to be the result of hyperconjugative interactions be-
tween the n(O) and σ*(P–C) orbitals,[3] while simultaneously dis-
missing any appreciable delocalisation of the phosphorus lone
pair into the carbonyl group (cf. amides) that might mitigate
the “weakening” effect, while earlier work invoked pπ–dπ inter-
actions in a similar context.[4] Notwithstanding, the conceptual
analogy to amides, first defined by Issleib,[5] persists, being in-
voked for systems with low-energy acyl stretches (< 1700 cm–1),
lying in the region typical of amides. This notion has been fur-
ther evidenced by an observed increase in νC=O values upon P-
coordination of these molecules, attributed to sequestration of
the lone pair and thus loss of delocalisation.[6]
fragments;
however,
trans-Rh(CO)(L)2Cl
(L
=
PH2-
{C(O)Me}, PPh2{C(O)C7F15}, PPh2{C(O)p-An}[6]) and [Rh{κ2-P,P-
C6H3N{PC(O)PPh2}2-2,6}Cl][13a] are the only low-valent group 9
complexes known. Similarly, until recently only [Ni(CO)3-
(PAd{C(O)tBu}2)],[12h] cis-[Pt(PPh2{C(O)C6H5})2Cl2] and cis-
[Pd(PPh2){C(O)C6H5}2-(SnCl3)Cl][15] were known from group 10,
though complexes of the bis(phosphomides) C6H4{PC(O)PPh2}2-
1,3 (Ni, Pd)[13b] and C6H3N{PC(O)PPh2}2-2,6 (Ni, Pd, Pt)[13a] have
since been described. Moreover, we have recently communi-
cated the formally related cyclophane 1, along with its platinum
complexes [Pt(κ1-1)2Cl2] and [{Pt(PEt3)Cl2}2{μ-1}].[16]
Herein, we describe the facile synthesis of a series of aroyl-
phosphane derivatives and their coordination chemistry with
representative platinum group metals. The synthesis and coor-
dination chemistry of 1 has previously been reported in prelimi-
nary form.[16]
The coordination chemistry of such “phosphomide” ligands
is, nonetheless, scant and largely restricted to groups 6–8 (Cr,[7]
Mo,[7,8] W,[9] Mn,[10] Re,[11] Fe,[12] Ru[13]) with an emphasis on the
Results and Discussion
Synthesis of Aroylphosphane Ligands
[a] Department of Chemistry, University of Sussex,
Brighton, UK
The aroylphosphanes 2–5 are obtained in good yield (> 70 %)
from the reaction of the respective aroyl chloride and HPPh2
(Scheme 1) and isolated upon removal of volatiles. We have
similarly prepared the bis(phosphomides) C6H4{C(O)PPh2}2-1,3
(6)[13a] and C5H3N{C(O)PPh2}2-2,6 (7),[13b] which were independ-
E-mail: i.crossley@sussex.ac.uk
http://www.sussex.ac.uk/lifesci/crossleylab
Supporting information and ORCID(s) from the author(s) for this article are
available on the WWW under http://dx.doi.org/10.1002/ejic.201600592.
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Full Paper
ently reported during the course of our works. We note that, ent, the intersubstituent angles remain consistent with the gen-
while condensation reactions are commonly employed for such eral range recorded in the CCDC database (98–102°) for tertiary
syntheses, there is typically need for either extraneous base (to phosphanes; the slightly more truncated angles in 1 correspond
sequester HCl) or premetallation of the secondary phosphane, to the intracyclic angles and can thus be attributed to the con-
neither of which have we found to be necessary. While the strained geometry.
participation of the phosphane itself as base in these reactions
cannot be fully excluded, there is no evidence for the genera-
tion of [Ph2PH2]Cl; moreover, the presence of traces of HPPh2
in the crude products, taken alongside the high isolated (pure)
yields of 2–7 are also inconsistent with the former serving as
stoichiometric base. Indeed, the reactions require careful con-
trol of the equimolar reagent stoichiometries, the presence of
excess HPPh2 leading to significant contamination (ca. 50 % by
NMR spectroscopy) with intractable by-products.
Figure 1. Molecular structure of 8 in crystals of the diethyl ether solvate with
thermal ellipsoids at the 50 % probability level and hydrogen atoms omitted
for clarity.
Scheme 1. Synthesis of aroylphosphanes 2–7.
Table 1. Selected, comparative geometric parameters [Å, °] with standard un-
certainties in parentheses, for 1, [Pt(1)2Cl2] and 8.
The identities of 2–7 follow from NMR spectroscopic data,
those for 4–7 being consistent with previous reports, against
which the novel 2 and 3 compare well, their bulk purity being
confirmed by microanalytical data. It is noteworthy that for this
series of compounds (and indeed 1) the strong infrared absorb-
ances associated with the carbonyl moiety all fall in the region
1630–1650 cm–1. This region has been previously considered
indicative of appreciable delocalisation of the phosphorus lone
pair into the carbonyl group, viz. true “phosphomide” character.
On this basis, compounds 2–7 would seem to be among the
most pronounced examples of this behaviour, as compared
with the archetypal Ph2PC(O)Me (1670 cm–1),[5] and
CF3(CF2)6C(O)PPh2 (1686 cm–1)[6] for which partial delocalisation
was invoked. Notwithstanding, the contribution of any such ca-
nonical form is clearly minimal, NMR spectroscopic features (viz.
1[16]
[Pt(1)2Cl2][16]
8
C–O
1.210(3)
1.202(3)
1.211(3)
1.220(3)
1.892(3)
1.890(3)
1.894(3)
1.866(3)
120.7(2)
120.0(2)
120.4(2)
120.6(2)
117.5(2)
118.2(2)
117.1(2)
117.3(2)
121.8(3)
121.8(3)
122.5(3)
122.1(3)
95.7(1)[c]
98.7(2)
1.208(4)[a]
1.201(4)[a]
1.215(4)[b]
1.214(4)[b]
1.896(3)[a]
1.897(3)[a]
1.890(4)[b]
1.895(4)[b]
115.6(3)[a]
115.7(3)[a]
119.1(3)[b]
119.2(3)[b]
121.5(2)[a]
121.9(2)[a]
119.1(2)[b]
119.0(2)[b]
122.8(3)[a]
122.3(3)[a]
121.9(3)
1.213(3)
1.213(3)
1.216(3)
P–C(O)
P–C–O
P–C–C
O–C–C
C–P–C
1.897(2)
1.892(2)
1.896(2)
114.1(2)
113.7(2)
112.9(2)
120.7(2)
120.6(2)
121.3(2)
1
δP, δC, JPC) being wholly consistent with fully saturated phos-
125.2(2)
125.7(2)
125.8(2)
phorus and classical ketone moieties, with no evidence for mul-
tiple-bonding in the P–C linkage. Indeed, this situation is re-
flected in the structurally characterised cyclophane 1,[16] which
exhibits carbonyl stretches of 1657 and 1639 cm–1,[17] but no
geometric deviations to imply delocalisation, either in the solid
state, or as computed for the gas phase.[18]
Indeed, key geometric parameters for 1 are comparable to
those of O=P{C(O)C6H4Me-2}3 (8,[19,20] Figure 1, Table 1) in
which the lone pair is sequestered. Moreover, upon formation
of [Pt(1)2Cl2][16] the acyl linkages adjacent to the coordination
site [dC=O = 1.201(4), 1.208(4) Å] remain comparable to those
121.7(3)
101.8(2)[a]
102.0(2)[a]
104.6(2)[a,c]
99.2(2)[b]
97.9(1)[c]
100.1(1)[c]
[c]
100.1(1)
95.1(1)[c]
99.6(1)
99.4(1)
98.7(2)[b]
100.7(1)
97.7(2)[b,c]
[a] Proximal to P→Pt. [b] Distal from P→Pt. [c] C(O)–P–C(O).
While structural data for 2–7 are not available, a comparable
distal [dC=O = 1.215(4), 1.214(4) Å] and those within the free scenario would seem likely, given also the minimal changes in
ligand [dC=O = 1.211(3), 1.202(3), 1.220(3), 1.210(3) Å], while the νCO values noted upon coordination to transition metal atoms
P–C(O) linkages are similarly unperturbed [1.890(4)–1.897(3) Å, (vide infra). It is also noteworthy that the greater variation in
cf. 1.886(3)–1.894(3) Å for 1]. Though marginally distorted the magnitude of the νCO values results from its sensitivity to
pyramidal geometries about the phosphorus atom are appar- aryl substitution patterns, which correlate with Hammett pa-
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Full Paper
rameters.[21] Taken together, these data imply negligible contri-
butions from a “phosphomide” canonical form within the free
acylphosphanes, and may additionally raise questions as to the
validity of using νCO values as an indicator in this context, or
indeed for the manifestation of hyperconjugative or pπ–dπ con-
tributions.
Coordination Chemistry
Compounds 2–5 each react readily with [Rh(η4-C8H12)Cl]2, ef-
fecting dimer cleavage to afford [Rh(η4-C8H12)(L)Cl] (L = 2–5;
Scheme 2, complexes 9–12, respectively) as yellow or orange
solids in high yield. In each case, a coordination shift of the
phosphorus NMR resonance (ΔδP ≈ +25 ppm) is accompanied
by appreciable coupling to the rhodium atom (1JRhP ≈ 140 Hz),
both comparable to those reported for [Rh(CO)2(L)Cl] [L =
Ph2PC(O)R; R = C6H4OMe-2, Me, (CF2)6CF3],[6] the only precedent
RhI “phosphomide“ complexes. Retention of the (symmetry-bro-
Scheme 3. Coordination chemistry of 2–5 with platinum(II).
1:1 reaction with [Pt(η4-C8H12)2Cl2], affording a 1:1 mixture of
1
cis-[Pt(4)2Cl2] (cis-20; δP = 16.1 ppm, JPtP = 3504 Hz) and unre-
acted [Pt(η4-C8H12)2Cl2], as determined on the basis of multinu-
clear NMR spectroscopy. Separation of this mixture has proven
impracticable, while the stoichiometric reaction yields an en-
tirely different species (δP = 26.1 ppm, devoid of 195Pt-31P cou-
pling), which remains unidentified. The chemistry of 4 in this
context has not been further pursued.
1
ken) cyclooctadiene ligand is apparent from H NMR spectro-
scopic data, while the bulk purity was confirmed by microanaly-
sis. Similarly, the palladium complexes [Pd(L)2Cl2] (Scheme 2,
13–16, respectively) are readily obtained from 2:1 reactions of
2–5 with [Pd(η4-C8H12)Cl2], and verified by NMR spectroscopic
data (ΔδP = +12 ppm) and microanalysis. In each case, the ex-
clusive product is assigned as the trans isomer, on the basis of
the manifestation of virtual triplets for the 13C{1H} NMR reso-
nances associated with the phosphorus substituents (Ar1, C=
O).[22,23]
It is noteworthy that, as with previously reported phos-
phomide ligands, an increase in the νCO value (Table 2) is ob-
served upon the coordination of 2–5. Such change has been
considered previously to imply a reduced contribution from the
–
phosphomide canonical form (i.e. O–C=PR2) due to sequestra-
tion of the lone pair.[6] However, this model would seem incom-
patible with recent computational studies[3] and our own obser-
vations (vide supra), which both imply limited, even negligible,
levels of lone-pair delocalisation within the free ligands. Indeed,
while a superficial correlation between the metal oxidation
state and magnitude of Δν is apparent, which might be consist-
ent with lone-pair sequestration arguments, correlation might
also be drawn to metal basicity, given the established π-acid
character of aroylphosphanes.[6] This might imply partial conju-
gation of the carbonyl π-system and C–P linkage, akin to
Kostyanovsky's proposed, albeit outdated, pπ→dπ model, in-
creases in νCO values being indicative of competitive donation
from the metal to P-based acceptor orbitals. However, we are
not currently in a position to make a decisive comment.
[a,b]
Table 2. Acyl stretching frequencies (νCO
)
for 2–5 and their coordination
complexes.
Scheme 2. Coordination chemistry of 2–5 toward rhodium and palladium.
L
Free
[Rh(C8H12)(L)Cl]
[Pd(L)2Cl2]
[Pt(L)2Cl2]
The chemistry of platinum, however, is somewhat more com-
plex and highly dependent on the ligand (Scheme 3). Thus, 2
reacts with [Pt(NCPh)2Cl2] (0.5 equiv.) to afford an approxi-
mately statistical mixture of cis-/trans-[Pt(2)2Cl2] (17; 55:45 %),
2
3
4
5
1634
1645
1648
1650
1657
1656
1663
1660
1660
1667
1669
1666
1659
1669
1670
1666
1
[a] In cm–1. [b] As neat solids on an ATR diamond cell.
distinguished from the magnitude of JPtP (JPtP-cis = 3505 Hz;
JPtP-trans = 2546 Hz) and the presence of virtual coupling for
trans-17, discernible in the 13C{1H} NMR spectrum. In contrast,
both 3 and 5 react under comparable conditions to afford ex-
clusively cis-18 and 19.
Conclusions
The coordination chemistry of 4, however, would appear We have described the facile synthesis of a family of aroylphos-
somewhat more precocious, the free phosphomide being re- phanes, including novel 3-alkyl deriviatives, by mild and base-
covered unchanged from the reaction with both [Pt(NCPh)2Cl2] free condensation protocols. The coordination chemistry of sev-
and [PtCl2]n, though its coordination was achieved through the eral of these ligands toward Rh, Pd and Pt salts has been de-
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C6H4{C(O)Cl}(Me-3) (1.07 g, 6.95 mmol) as solution in diethyl ether.
The resulting colourless solution was stirred for 30 min before being
allowed to attain ambient temperature, whereupon a yellow colou-
ration was assumed. The mixture was stirred for 1 h. Removal of
the volatiles under reduced pressure afforded 1 as a crude yellow
solid, which was washed with pentane and dried in vacuo. Yield:
1.41 g, 67 %. NMR (C6D6, 30 °C): 1H NMR: δH = 1.88 (s, 3 H, CH3),
scribed, affording the first systematic series of aroylphosphane
complexes of the platinum-group metals, thus significantly in-
creasing the documented coordination compounds of such li-
gands.
Consideration of the structural features of the macrocyclic
aroylphosphane 1, and the phosphine oxide 8, alongside spec-
troscopic data for the full series of ligands, lead us to conclude
a negligible extent of n(P) delocalisation within the free ligands,
raising question as to the validity of invoking νCO values in the
assessment of “phosphomide” character – particularly given its
sensitivity to arene substitution patterns. Consequently, noted
increases in νCO values upon coordination cannot be attributed
to loss of lone-pair delocalisation, though we cannot currently
offer a definitive comment on the origin of this effect.
3
3
6.81 (d, JHH = 7.4 Hz, 1 H, CH4), 6.87 (t, JHH = 7.7 Hz, 1 H, CH5),
7.01 (m, 6 H, m-Ph, p-Ph), 7.50 (m, 4 H, o-Ph), 7.96 (s, 1 H, CH2), 7.99
(d, JHH = 7.7 Hz, 1 H, CH6) ppm; 13C{1H} NMR: δC = 21.0 (s, CH3),
3
126.3 (d, JPC = 11 Hz, C6H), 128.6 (s, C5H), 128.8 (s, C2H), 128.9 (d,
3
3JPC = 8 Hz, m-Ph), 129.5 (s, p-Ph), 133.9 (s, C4H), 135.3 (d, JPC
=
20 Hz, o-Ph), 138.6 (s, C3Me), 140.2 (d, JPC = 36 Hz, C1), 211.8 [d,
2
1JPC = 37 Hz, C(O)P] ppm; 31P{1H} NMR: δP = 12.4 ppm. IR: ν = 1634
˜
(νCO) cm–1. C20H17OP (304.33): calcd. C 78.93, H 5.63; found C 78.84,
H 5.47.
C6H4{C(O)PPh2}(CH2Cl-3) (3): As for 1 using HPPh2 (0.701 g,
Experimental Section
3.76 mmol) and C6H4{C(O)Cl}(CH2Cl-3) (0.712 g, 3.76 mmol). Yield:
1
1.13 g, 89 %. NMR (C6D6, 30 °C): H NMR: δH = 3.83 (s, 2 H, CH2Cl),
General Methods: All manipulations were performed under strict
anaerobic conditions using standard Schlenk line and glovebox
(MBraun) techniques, working under dry argon or dinitrogen, re-
spectively. Solvents were distilled from appropriate drying agents
and stored over either molecular sieves (4 Å for DCM and THF)
or potassium mirrors. Aroyl chlorides, HPPh2 and P(SiMe3)3 were
obtained from Sigma–Aldrich and used as supplied. Precious metal
salts (PtCl2, PdCl2) were obtained from STREM and used as supplied;
[RhCl(1,5-cod)]2 was previously prepared according to literature
methods.[24] Deuterated solvents were supplied by Goss Scientific
and purified by refluxing in the presence of potassium (hydro-
carbon) or CaH2 (chlorinated) for 3 d prior to use, being vacuum-
transferred and stored under an inert gas. NMR spectra were re-
corded with a Varian V NMR S 400 (1H, 399.50 MHz; 13C, 100.46 MHz;
31P, 161.71 MHz; 195Pt, 85.53 MHz) or V NMR S 500 (1H 499.91 MHz;
13C, 125.72 MHz) spectrometer. All spectra were referenced to
Me4Si, 85 % H3PO4 or K2PtCl6 as appropriate. 13C NMR spectroscopic
data were assigned with recourse to 2D (HSQC, HMBC) spectra; de-
tailed connectivity was assessed using 1H-31P HMBC spectra. Ele-
mental analyses were obtained by Mr. S. Boyer of the London Met-
ropolitan University Elemental Analysis Service. Infrared spectra
were recorded with a Perkin-Elmer Spectrum One instrument. Mass
spectra were obtained by Dr A. Abdul-Sada of the departmental
service, using a VG Autospec Fisons instrument (FAB+) with a 3-
nitrobenzyl alcohol matrix.
3
3
6.77 (t, JHH = 7.6 Hz, 1 H, CH5), 6.88 (d, JHH = 7.5 Hz, 1 H, CH4),
7.01 (m, 6 H, m-Ph, p-Ph), 7.47 (m, 4 H, o-Ph), 7.96 (dq, JHH = 7.7,
J
HH = 1.4 Hz, 1 H, CH6), 8.03 (d, JHH = 7.7 Hz, 1 H, CH2) ppm; 13C{1H}
NMR: δC = 45.2 (s, CH2Cl), 128.3 (obscured, C2H), 128.5 (d, JPC
=
10 Hz, C6H), 128.9 (d, JPC = 8 Hz, m-Ph), 129.0 (d, JPC = 1 Hz, C5H),
3
129.6 (s, p-Ph), 132.9 (d, JPH = 1.5 Hz, C4H), 135.3 (d, JPC = 19 Hz,
3
o-Ph), 138.4 (d, JPC = 1 Hz, C3Me), 140.3 (d, JPC = 36 Hz, C1), 211.4
2
[d, JPC = 38 Hz, C(O)P] ppm; 31P{1H} NMR: δP = 12.9 ppm. IR: ν =
1
˜
1645 (νCO) cm–1. C20H16ClOP (338.77): calcd. C 70.91, H 4.76; found
C 70.90, H 4.73.
C6H4{C(O)PPh2}(CO2Me-4) (4): As for 1 using HPPh2 (0.572 g,
3.07 mmol) and C6H4{C(O)Cl}(CO2Me-4) (0.610 g, 3.07 mmol). Yield:
1
0.853 g, 80 %. NMR (C6D6, 30 °C): H NMR: δH = 3.35 (s, 3 H, CH3),
3
7.00 (m, 6 H, m-Ph, p-Ph), 7.42 (m, 4 H, o-Ph), 7.84 (d, JHH = 8.4 Hz,
3
4
2 H, CH3,5), 7.97 (dd, JHH = 6.8, JHH = 1.8 Hz, 2 H, CH2,6) ppm;
13C{1H} NMR: δC = 51.7 (s, CH3), 128.2 (obscured, C2,6H), 129.0 (d,
3JPC = 8 Hz, m-Ph), 129.7 (s, C3,5H), 130.0 (s, p-Ph), 134.2 (s, C4), 135.3
3
2
(d, JPC = 19 Hz, o-Ph), 142.9 (d, JPC = 35 Hz, C1), 165.6 (s, CO2Me),
212.1 [d, 1JPC = 39 Hz, C(O)P] ppm; 31P{1H} NMR: δP = 14.4 ppm. ν =
˜
1721 (CO2Me), 1649 (νC=O) cm–1. FAB-MS: m/z = 349 [MH]+.
C6H4{C(O)PPh2}(CN-4) (5): As for
1 using HPPh2 (0.741 g,
3.98 mmol) and C6H4{C(O)Cl}(CN-4) (0.659 g, 3.98 mmol). Yield:
3
1.00 g, 80 %. NMR (C6D6, 30 °C): 1H NMR: δH = . = 6.71 (d, JHH
=
8.4 Hz, 2 H, CH3,5), 7.01 (m, 6 H, m-Ph, p-Ph), 7.35 (m, 4 H, o-Ph),
7.63 (dd, 3JHH = 8.5 Hz, 2 H, CH2,6) ppm. 13C{1H} NMR: δC = 116.5 (s,
Synthesis
m-{-C(O)-C6H4(C(O)PMe)}2 (1): To a diethyl ether solution of
MeP(SiMe3)2 (0.66 g, 2.27 mmol), cooled to –78 °C, was added m-
C6H4{C(O)Cl}2 (0.46 g, 2.27 mmol) as solution in diethyl ether, lead-
ing to immediate formation of a yellow precipitate, suspended in a
yellow supernatant solution. After stirring at –78 °C for 30 min, the
mixture was allowed to attain ambient temperature and stirred for
a further 12 h. The solution was then removed by filtration and the
C4), 117.9 (s, C≡N), 128.2 (obscured, C2,6H), 129.1 (d, JPC = 8 Hz, m-
3
Ph), 129.9 (s, p-Ph), 132.3 (s, C3,5H), 135.3 (d, JPC = 19 Hz, o-Ph),
3
141.9 (d, 2JPC = 38 Hz, C1), 212.5 [d, 1JPC = 39 Hz, C(O)P] ppm. 31P{1H}
NMR: δP = 14.5 ppm. ν = 2229 (νCN), 1650 (νC=O) cm–1. FAB-MS:
˜
m/z = 349 [MH]+.
C6H4{C(O)PPh2}2-1,3 (6): In a manner analogous to that used for 1
using 2 equiv. of HPPh2 (0.504 g, 2.71 mmol) and 1 equiv. of iso-
phthaloyl chloride (0.275 g, 1.35 mmol) in THF. Yield: 0.574 g, 85 %.
precipitate washed with diethyl ether and dried in vacuo. Yield:
0.320 g, 79 %. NMR (C6D6, 30 °C): 1H NMR: δH = 1.58 (d, JPH
=
2
3
3
3.1 Hz, 6 H) 6.45 (t, JHH = 1.75 Hz, 2 H), 7.15 (d, JHH = 1.67 Hz, 4
1
3
NMR (C6D6, 30 °C): H NMR: δH = 6.66 (t, JHH = 7.9 Hz, 1 H, CH5),
H), 9.28 (br., 2 H) ppm; 13C{1H} NMR: δC = 1.7 (d, JCP = 4.5 Hz, Me),
1
6.99 (m, 8 H, m-Ph), 7.01 (m, 4 H, p-Ph), 7.40 (m, 8 H, o-Ph), 7.90 (dt,
130.3 (JCP = 1.6 Hz, Cm), 130.6 (dd, JCP ≈ 2 Hz, Co,p), 134.0 (t, JCP
=
3
3
3JPH = 7.8, JHH = 1.5 Hz, 2 H, CH4,6), 9.02 (m, 1 H, C2) ppm; 13C{1H}
13.9 Hz, Co), 137.6 (d, JCP = 37.9 Hz, Ci), 205.9 (d, JCP = 46.0 Hz, C=
NMR: δC = 128.4 (obscured, C2H), 128.6 (obscured, C5), 129.0 (d,
O) ppm; 31P{1H} NMR: δP = 32.7 (s) ppm. IR: ν = 1656, 1639 (νCO
)
3JPC = 8 Hz, m-Ph), 129.7 (s, p-Ph), 132.1 (d, 3JPC = 9 Hz, C4,6H), 133.1
˜
cm–1. C18H14O4P2 (356.25): calcd. C 60.67, H 3.93; found C 60.59, H
3.82.
1
2
2
(d, JPC = 6 Hz, i-Ph), 135.3 (d, JPC = 18 Hz, o-Ph), 139.9 (d, JPC
=
=
38 Hz, C1,3), 211.2 [d, JPC = 38 Hz, C(O)P] ppm; 31P{1H} NMR: δP
1
C6H4{C(O)PPh2}(Me-3) (2): To a diethyl ether solution of HPPh2
12.9 ppm. ν = 1642, 1588 (νCO) cm–1. C32H24O2P2 (502.49): calcd. C
˜
(1.29 g, 6.95 mmol), cooled to –78 °C, was added dropwise 76.49, H 4.81; found C 76.42, H 4.80.
Eur. J. Inorg. Chem. 2016, 4076–4082
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4079 © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Full Paper
C5H3N{C(O)PPh2}2-2,6 (7): As for 5, using HPPh2 (0.617 g,
7.47 (m, 2 H, p-Ph), 7.53 (t, JHH = 7.7 Hz, 1 H, CH5), 7.64 (br. s, 2 H,
3.32 mmol) and 1 equiv. of C5H3N{C(O)Cl}2-2,6 (0.338 g, 1.67 mmol) CH4), 7.65–7.67 (m, 4 H, o-Ph), 8.73 (br. d, JHH = 7.5 Hz, 1 H, CH6),
1
in THF. Yield: 0.623 g, 74 %. NMR (C6D6, 30 °C): H NMR: δH = 6.71
8.81 (br. s, 1 H, CH2) ppm; 13C{1H} NMR: δC = 29.2 (s, COD-CH2), 33.2
(s, COD-CH2), 46.0 (s, CH2Cl), 71.4 (d, JRhC = 13 Hz, COD-CH), 105.8
(d, 3JHH = 7.9 Hz, 1 H, CH5), 7.03 (m, 4 H, p-Ph), 7.09 (m, 8 H, m-Ph),
3
7.42 (d, JHH = 7.4 Hz, 2 H, CH4,6), 7.63 (m, 8 H, o-Ph) ppm; 13C{1H} (d, JRhC = 11, JPC = 7 Hz, COD-CH), 128.5 (d, JPC = 10 Hz, m-Ph),
3
3
NMR: δC = 123.2 (t, JPC = 2 Hz, C4,6H), 128.7 (d, JPC = 8 Hz, m-Ph),
129.0 (s, C5H), 130.9 (d, JPC = 2 Hz, p-Ph), 130.8 (d, JPC = 3 Hz, C6H),
131.2 (d, JPC = 4 Hz, C2H), 133.9 (s, C4H) 135.5 (d, JPC = 10 Hz, o-Ph),
1
3
129.3 (s, p-Ph), 134.3 (d, JPC = 6 Hz, i-Ph), 135.4 (d, JPC = 20 Hz, o-
Ph), 153.4 (d, 2JPC = 38 Hz, C1,3), 213.5 [d, 1JPC = 40 Hz, C(O)P] ppm.
138.0 (s, C3), 202.1 [br., C(O)P] ppm; 31P{1H} NMR: δP = 36.4 (JRhP
=
31P{1H} NMR: δP = 16.6 ppm. ν = 1650 (νC=O) cm–1. C31H23NO2P2 146 Hz) ppm. ν = 1657 (νC=O) cm–1. C28H28Cl2OPRh (585.31): calcd.
˜
˜
(503.48): calcd. C 73.95, H 4.60, N 2.78; found C 73.82, H 4.55, N
C 57.46, H 4.82; found C 57.43, H 4.75.
2.88.
[Rh(η4-C8H12){PPh2C(O)C6H4CO2Me-4}Cl] (11): As for 9 using
O=P{C(O)C6H4Me-2}3 (8): To a diethyl ether solution of P(SiMe3)3
(1.21 g, 4.84 mmol) kept at –78 °C was added C6H4(COCl)(Me-2)
(2.24 g, 14.5 mmol) as solution in diethyl ether. After stirring at
–78 °C for 30 min, the mixture was warmed to ambient temperature
and stirred for a further 48 h, whereupon a yellow precipitate was
formed. Volatiles were removed under reduced pressure, then the
solid washed with pentane and dried in vacuo. Yield: 1.66 g, 68 %.
[Rh(η4-C8H12)Cl]2 (0.197 g, 0.40 mmol) and 4 (0.278 g, 0.80 mmol).
1
Yield: 0.205 g, 86 %. NMR (CDCl6, 30 °C): H NMR: δH = 2.07 (br. m,
2 H, COD-CH2 exo), 2.16 (br. m, 2 H, COD-CH2 exo), 2.49 (br., 4 H, COD-
CH2 endo), 3.43 (br. s, 2 H COD-CH), 5.60 (br. s, 2 H, COD-CH), 3.97 (s,
3 H, CH3), 7.32–7.39 (m, 4 H, m-Ph), 7.41–7.46 (m, 2 H, 9-Ph), 7.58–
3
3
7.65 (m, 4 H, o-Ph), 8.18 (d, JHH = 8 Hz, 2 H, CH3,5), 8.87 (d, JHH
=
8 Hz, 2 H, CH2,6) ppm; 13C{1H} NMR: δC = 29.2 (s, COD-CH2), 38.9 (s,
COD-CH2), 52.7 (s, CH3), 71.4 (d, JRhC = 14 Hz, COD-CH), 106.0 (d,
JRhC = 11, JRhC = 7 Hz, COD-CH), 128.6 (d, JPC = 10 Hz, m-Ph), 129.8
(s, C3,5H), 130.7 (d, JPC = 4 Hz, C2,6H), 131.0 (d, JPC = 2 Hz, p-Ph),
135.4 (d, JPC = 11 Hz, o-Ph), 141.7 (d, JPC = 42 Hz, C1), 166.3 (s,
CO2Me), 202.5 [d, JPC = 18 Hz, C(O)P] ppm. 31P{1H} NMR: δP = 36.9
1
NMR (C6D6, 30 °C): H NMR: δH = 2.51 (s, 9 H, CH3) 6.84 (m, 3 H, p-
CH), 6.93 (m, 6 H, m-CH), 8.04 (m, 3 H, o-CH) ppm; 13C{1H} NMR:
3
δC = 21.1 (s, CH3), 125.7 (s, p-CH), 131.5 (d, JPC = 15.8 Hz, o-CH),
4
4
132.1 (d, JPC = 1.3 Hz, m-CH), 132.4 (d, JCP = 2.7 Hz, m-CH), 138.8
3
2
1
(d, JPC = 3.7 Hz, o-C), 140.8 (d, JPC = 33.3 Hz, i-C), 208.9 (d, JCP
=
34.8 Hz, C=O) ppm; 31P{1H} NMR: δP = 67.2 (s) ppm. C24H21O4P1
(JRhP = 146.9 Hz) ppm. ν = 1718, 1663 (νC=O) cm–1. C29H29ClO3PRh
˜
(404.40): calcd. C 71.28, H 5.23; found C 71.42, H 5.19.
(594.88): calcd. C 58.55, H 4.91; found C 58.42, H 4.96.
Crystal Data for 8: C24H21O4P·(0.5Et2O), Mw = 441.46, triclinic, P1
[Rh(η4-C8H12){PPh2C(O)C6H4CN-4}Cl] (12): As for 9 using [Rh(η4-
¯
(Nno. 2), a = 8.6469(4), b = 12.0839(5), c = 12.5443(4) Å, α = C8H12)Cl]2 (0.072 g, 0.145 mmol) and 5 (0.091 g, 0.289 mmol). Yield:
106.344(2), ꢀ = 92.601, γ = 110.101(2)°, V = 1166.29(8) Å3, Z = 2, 0.070 g, 86 %. NMR (CD2Cl2, 30 °C): H NMR: δH = 2.09 (br. m, 2 H,
1
Dc = 1.257 Mg/m–3, μ(Mo-Kα) = 0.149 mm–1, T = 173(2) K, 5249
independent reflections, full-matrix F2 refinement, R1 = 0.0599,
wR2 = 0.1765 on 5249 independent absorption-corrected reflections
COD-CH2 exo), 2.20 (br. m, 2 H, COD-CH2 exo), 2.48 (br., 4 H, COD-
CH2 endo), 3.45 (br. s, 2 H, COD-CH), 5.57 (br. s, 2 H COD-CH), 7.36–
7.42 (m, 4 H m-Ph), 7.45–7.51 (m, 2 H p-Ph), 7.55–7.62 (m, 4 H o-
[I > 2σ(I); 2θmax = 55.08°], 289 parameters. CCDC 1480086 (for 8) Ph), 7.85 (d, JHH = 8 Hz, 2 H, CH3,5), 8.86 (d, JHH = 8 Hz, 2 H, CH2,6
)
contains the supplementary crystallographic data for this paper.
These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre.
[Rh(η4-C8H12){PPh2C(O)C6H4Me-3}Cl] (9): To a solution of [Rh(η4-
C8H12)Cl]2 (0.184 g, 0.37 mmol) in dichloromethane was added, at
ambient temperature, 2 (0.227 g, 0.75 mmol) resulting in the imme-
diate formation of an orange solution, stirring of which was contin-
ued overnight. After removal of the solvent under reduced pressure,
the crude material was washed with pentane, then dried in vacuo
ppm; 13C{1H} NMR: δC = 29.6 (s, COD-CH2), 33.5 (s, COD-CH2), 72.2
(d, JRhC = 13 Hz, COD-CH), 107.0 (d, JRhC = 12, JRhC = 7 Hz, COD-CH),
117.3 (s, C4), 118.6 (s, C≡N), 129.1 (d, JPC = 9 Hz, m-Ph), 131.6 (d,
JPC = 2 Hz, p-Ph), 131.3 (d, JPC = 3 Hz, C2,6H), 132.9 (s, C3,5H), 135.8
(d, JPC = 11 Hz, o-Ph), 141.9 (d, JPC = 43 Hz, C1), 203.0 [d, JPC
=
17 Hz, C(O)P] ppm; 31P{1H} NMR: δP = 37.8 (JRhP = 147.1 Hz) ppm.
ν = 2229 (νCN), 1660 (νC=O) cm–1. C28H26ClNOPRh (561.85): calcd. C
˜
59.86, H 4.66, N 2.85; found C 59.85, H 4.95, N 2.57.
trans-[Pd{PPh2C(O)C6H4Me-3}2Cl2] (13): To a solution of [Pd(η4-
to afford 9 as a yellow solid. Yield: 0.155 g, 76 %. NMR (C6D6, 30 °C): C8H12)Cl2] (0.085 g, 0.297 mmol) in dichloromethane were added at
1H NMR: δH = 1.99–2.07 (br. m, 2 H, COD-CH2 exo), 2.08–2.15 (br. m, ambient temperature 2 equiv. of 2 (0.181 g, 0.595 mmol) resulting
2 H, COD-CH2 exo), 2.41–2.54 (br. m, 4 H, COD-CH2 endo), 2.47 (s, 3 H,
CH3), 3.42 (br. s, 2 H, COD-CH), 5.61 (br. s, 2 H, COD-CH), 7.32–7.37
(m, 4 H, m-Ph), 7.39–7.45 (m, overlapped, 4 H, CH4, CH5, p-Ph), 7.62–
7.69 (m, 4 H, p-Ph), 8.51 (br. s, 1 H, CH2), 8.71 (dd, JHH/JPH ≈ 4 Hz, 1
H, CH6) ppm; 13C{1H} NMR: δC = 21.7 (s, CH3), 29.2 (d, JRhC = 1 Hz,
COD-CH2), 33.2 (d, JRhC = 3 Hz, COD-CH2), 71.0 (d, JRhC = 14 Hz,
in the immediate formation of a yellow solution, stirring of which
was continued overnight. After removal of the solvent under re-
duced pressure, the crude material was washed with pentane, then
dried in vacuo to afford 13 as a yellow solid. Yield: 0.217 g, 93 %.
1
NMR (CDCl3, 30 °C): H NMR: δH = 2.32 (s, 6 H, CH3), 7.26 (m, 2 H,
CH4), 7.32 (m, 2 H, CH5), 7.36 (m, 8 H, m-Ph), 7.45 (m, 4 H, p-Ph),
3
COD-CH), 105.4 (dd, JRhC = 12, JPC = 7 Hz, COD-CH), 128.4 (d, JPC
=
7.75 (m, 8 H, o-Ph), 8.09 (s, br. 2 H, CH2), 8.25 (d, JHH = 7.8 Hz, 2 H,
10 Hz, m-Ph), 128.4 (s, C5H), 128.6 (d, JPC = 4 Hz, C6H), 129.8 (d, CH6) ppm; 13C{1H} NMR: δC = 21.5 (s, CH3), 126.9 (t, JPC = 22 Hz, C1),
JPC = 40 Hz, i-Ph), 130.7 (d, JPC = 2 Hz, p-Ph), 131.2 (d, JPC = 4 Hz,
127.9 (t, JPC = 2 Hz, C6H), 128.5 (s, C4H), 128.6 (t, JPC = 4 Hz, m-Ph),
C2H), 134.9 (s, C4H), 135.6 (d, JPC = 11 Hz, o-Ph), 138.4 (s, C3H), 138.6 130.2 (t, JPC = 2 Hz, C2H), 131.3 (t, JPC = 1 Hz, p-Ph), 134.9 (s, C5H),
(d, JPC = 42 Hz, C1), 202.2 [d, JPC = 17 Hz, C(O)P] ppm; 31P{1H} NMR: 135.9 (t, JPC = 6 Hz, o-Ph), 137.2 (t, JPC = 23 Hz, i-Ph), 138.6 (s, C3),
δP = 36.1 (JRhP = 146 Hz) ppm. ν = 1657 (νC=O) cm–1. C28H29ClOPRh
198.9 [br., C(O)P] ppm; 31P{1H} NMR: δP = 25.8 (s) ppm. ν = 1660
˜
˜
(550.87): calcd. C 61.06, H 5.31; found C 60.93, H 5.18.
(νC=O) cm–1. C40H34Cl2O2P2Pd (785.96): calcd. C 61.13, H 4.36; found
C 61.02, H 4.45.
[Rh(η4-C8H12){PPh2C(O)C6H4CH2Cl-3}Cl] (10): As for
9 using
[Rh(η4-C8H12)Cl]2 (0.138 g, 0.28 mmol) and 3 (0.189 g, 0.56 mmol). trans-[Pd{PPh2C(O)C6H4CH2Cl-3}2Cl2] (14): As for 13 using [Pd(η4-
Yield: 0.124 g, 76 %. NMR (CDCl3, 30 °C): 1H NMR: δH = 2.00–2.10
(br. m, 2 H, COD-CH2 exo), 2.11–2.22 (br. m, 2 H, COD-CH2 exo), 2.43–
2.56 br. m, 4 H, COD-CH2 endo), 3.43 (br. s, 2 H, COD-CH), 4.68 (s,
CH2Cl), 5.63 (br. s., 2 H, COD-CH), 7.34–7.40 (m, 4 H, m-Ph), 7.41–
C8H12)Cl2] (0.042 g, 0.147 mmol) and 3 (0.100 g, 0.295 mmol). Yield:
0.117 g, 93 %. NMR (CDCl3, 30 °C): 1H NMR: δH = 4.50 (s, 4 H, CH2Cl),
7.34 (m, 2 H, C5H), 7.38 (m, 8 H, m-Ph), 7.47 (m, 4 H, p-Ph), 7.54 (t,
3JHH = 8.4 Hz, 2 H, C4H), 7.78 (dt, JHH = 6.4, JPH = 5.8 Hz, 8 H, o-
3
Eur. J. Inorg. Chem. 2016, 4076–4082
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4080
© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Full Paper
3
Ph), 8.23 (br. s, 2 H, C2H), 8.29 (d, JHH = 7.7 Hz, 2 H, C6H) ppm;
0.447 mmol) and 3 (0.303 g, 0.894 mmol). Yield: 0.217 g, 93 %. NMR
13C{1H} NMR: δC = 45.5 (s, CH2Cl), 126.2 (t, JPC = 23 Hz, i-Ph), 128.8 (C6D6, 30 °C): 1H NMR: δH = 4.58 (s, 4 H, CH2Cl), 7.22 (m, 8 H, m-Ph),
(t, JPC = 5 Hz, m-Ph), 129.0 (s, C5H), 129.6 (t, JPC = 2 Hz, C2H), 130.1
7.32 (m, 2 H, C5H), 7.41 (m, 4 H, p-Ph), 7.48 (m, 2 H, C4H), 7.50 (m,
(t, JPC = 2 Hz, C6H), 131.5 (s, p-Ph), 133.8 (s, C4H), 135.8 (t, JPC = 6 Hz, 8 H, o-Ph), 8.21 (d, JHH = 8.0 Hz, 2 H, C6H), 8.29 (br. s, 2 H, C2H)
3
o-Ph), 137.3 (t, JPC = 21 Hz, C1), 138.1 (s, C3), 198.8 [br., C(O)P] ppm;
31P{1H} NMR: δP cm–1
25.9 (s) ppm. 1657 (νC=O
ppm; 13C{1H} NMR: δC = 45.7 (s, CH2Cl), 124.8 (d, JPC = 58 Hz, i-Ph),
128.6 (d, JPC = 10, JPtC = 8 Hz, m-Ph), 128.9 (s, C5H), 130.0 (s,
C6H),130.1 (s, C2H), 132.0 (s, p-Ph), 133.6 (s, C4H), 135.8 (d, JPC = 10,
JPtC = 8 Hz, o-Ph), 136.7 (d, JPC = 40 Hz, C1), 137.8 (s, C3), 194.6
=
ν
˜
=
)
.
C40H32Cl4O2P2Pd (854.85): calcd. C 56.20, H 3.77; found C 56.24, H
3.74.
1
[C(O)P] ppm; 31P{1H} NMR: δP = 15.3 (s, JPtP = 3503 Hz) ppm;
trans-[Pd{PPh2C(O)C6H4(CO2Me)-4}2Cl2] (15): As for 13 using
[Pd(η4-C8H12)Cl2] (0.162 g, 0.567 mmol) and 4 (0.395 g, 1.13 mmol).
Yield: 0.452 g, 91 %. NMR (CDCl3, 30 °C): H NMR: δH = 3.95 (s, 6 H,
195Pt{1H} NMR: δPt = –4354 (t, 1JPtP = 3503 Hz) ppm. ν = 2229 (νCN),
˜
1668 (νC=O) cm–1. C40H32Cl4O2P2Pt (943.54): calcd. C 50.92, H 3.42;
1
3
found C 50.88, H 3.33.
CH3), 7.39 (m, 8 H, m-Ph), 7.48 (m, 4 H, p-Ph), 7.78 (dt, JHH = 6.9,
JPH = 5.6 Hz, 8 H, o-Ph), 8.01 (d, JHH = 8.5 Hz, 4 H, C3,5H), 8.31 (d,
3
cis-[Pt{PPh2C(O)C6H4CN-4}2Cl2] (19): Prepared in fashion compara-
ble to that for 17 using [Pt(NCPh)2Cl2] (0.211 g, 0.424 mmol) and 5
3JHH = 8.8 Hz, 4 H, C2,6H) ppm; 13C{1H} NMR: δC = 52.7 (s, CH3), 125.9
(t, JPC = 23 Hz, i-Ph), 128.9 (t, JPC = 5 Hz, m-Ph), 129.7 (t, JPC = 2 Hz,
1
(0.267 g, 0.848 mmol). Yield: 0.320 g, 84 %. NMR (CDCl3, 30 °C): H
C
2,6H), 129.8 (s, C3,5H), 131.7 (s, p-Ph), 135.7 (t, JPC = 6 Hz, o-Ph),
NMR: δH = 7.25 (m, 8 H, m-Ph), 7.40 (m, 4 H, p-Ph), 7.45 (m, 8 H, o-
140.1 (t, JPC = 23 Hz, C1), 166.1 (s, CO2) 199.2 [br., C(O)P] ppm;
31P{1H} NMR: δP = 26.1 (s) ppm. ν = 1720, 1670 (νC=O) cm–1
Ph), 7.60 (d, 3JHH = 8 Hz, 4 H, C3,5H), 8.21 (d, 3JHH = 8 Hz, 4 H, C2,6H)
ppm; 13C{1H} NMR: δC = 116.6 (s, C4), 117.8 (s, C≡N), 124.2 (t, JPC
=
.
˜
58 Hz, i-Ph), 128.8 (d, JPC = 11, JPtC = 10 Hz, m-Ph), 130.8 (s, C2,6H),
132.5 (s, m-Ph), 132.1 (s, C3,5H), 135.6 (d, JPC = 9, JPtC = 10 Hz, o-Ph),
139.5 (d, JPC = 49 Hz, C1), 194.8 [d, JPC = 44 Hz, C(O)P] ppm; 31P{1H}
C
4.03.
42H34Cl2O6P2Pd (873.98): calcd. C 57.72, H 3.92; found C 57.63, H
trans-[Pd{PPh2C(O)C6H4CN-4}2Cl2] (16): As for 13 using [Pd(η4-
C8H12)Cl2] (0.053 g, 0.187 mmol) and 5 (0.118 g, 0.375 mmol). Yield:
NMR: δP = 16.5 (s, JPtP = 3493 Hz) ppm; 195Pt{1H} NMR: δPt = 4374
1
(t, JPtP = 3493 Hz) ppm. ν = 2230 (νCN), 1666 (νC=O) cm–1
C
.
1
0.139 g, 92 %. NMR (CDCl3, 30 °C): H NMR: δH = 7.42 (m, 8 H, m-
˜
3
40H28Cl2N2O2P2Pt (896.62): calcd. C 53.58, H 3.15, N 3.12; found C
Ph), 7.54 (m, 4 H, p-Ph), 7.74 (dt, JHH = 7, JPH = 6 Hz, 8 H, o-Ph),
7.59 (d, JHH = 8.5 Hz, 4 H, C3,5H), 8.26 (d, JHH = 8.4 Hz, 4 H, C2,6H)
3
3
53.65, H 3.15, N 3.10.
ppm; 13C{1H} NMR: δC = 117.0 (s, C4), 117.8 (s, C≡N), 125.5 (t, JPC
=
cis-[Pt{PPh2C(O)C6H4(CO2Me)-4}2Cl2] (20): Prepared in a manner
similar to that for 17, but commencing from [Pt(η4-C8H14)Cl2]
(0.118 g, 0.316 mmol) and 4 (0.109 g, 0.316 mmol). Obtained as 1:1
mixture with [Pt(η4-C8H14)Cl2]. Yield (crude): 0.216 g. NMR (CDCl3,
30 °C): 1H NMR: δH = 3.94 (s, 6 H, CH3), 7.22 (m, 8 H, m-Ph), 7.41 (m,
24 Hz, i-Ph), 129.1 (t, JPC = 5 Hz, m-Ph), 129.9 (t, JPC = 2 Hz, C2,6H),
131.1 (s, p-Ph), 132.3 (s, C3,5H), 135.6 (t, JPC = 6 Hz, o-Ph), 139.8 (t,
J
PC = 23 Hz, C1), 198.7 [t, JPC = 12 Hz, C(O)P] ppm; 31P{1H} NMR: δP =
25.9 (s) ppm. ν = 2229 (νCN), 1666 (νC=O) cm–1. C40H28Cl2N2O2P2Pd
˜
(807.93): calcd. C 59.46, H 3.49, N 3.47; found C 59.58, H 3.52, N
3.48.
3
4 H, p-Ph), 7.47 (m, 8 H, o-Ph), 7.98 (d, JHH = 8.9 Hz, 4 H, C3,5H),
3
8.26 (d, JHH = 8.9 Hz, 4 H, C2,6H) ppm; [Pt(C8H12)Cl2]: δH = 2.26
cis-/trans-[Pt{PPh2C(O)C6H4Me-3}2Cl2] (17): To
a solution of
(m, 4 H, COD-CH2), 2.70 (m, 4 H, COD-CH2), 5.61 (m, JPtH = 66.7 Hz,
COD-CH)] ppm; 13C{1H} NMR: δC = 52.7 (s, CH3), 124.7 (d, JPC = 58 Hz,
i-Ph), 128.6 (t, JPC = 11, JPtC = 8 Hz, m-Ph), 129.5 (s, C3,5H), 130.5 (s,
[Pt(NCPh)2Cl2] (0.143 g, 0.303 mmol) in dichloromethane were
added at ambient temperature 2 equiv. of 2 (0.184 g, 0.605 mmol)
resulting in the immediate formation of a pale yellow solution, stir-
ring of which was continued overnight. After removal of the solvent
under reduced pressure, the crude material was washed with Et2O,
then pentane and dried in vacuo to afford 17 as a yellow solid.
C
2,6H), 132.2 (s, p-Ph), 135.7 (d, JPC = 10, JPtC = 8 Hz, o-Ph), 139.7 (d,
JPC 49 Hz, C1), 166.1 (s, CO2) 195.1 [d, JPC = 45 Hz, C(O)P] ppm;
[Pt(C8H12)Cl2]: δC = 31.1 (s, COD-CH2), 100.2 (s, JPtC = 152 Hz, COD-
CH), 5.61 (m, JPtH = 66.7 Hz)] ppm; 31P{1H} NMR: δP = 16.1 (JPtP
=
3504 Hz) ppm. ν = 1721 (νCO (ester)), 1670 (νCO) cm–1
.
Yield: 0.217 g, 93 %. ν =1661 (νC=O; br. absorption due to mixture
˜
˜
of isomers) cm–1. C40H34Cl2O2P2Pt (874.65): calcd. C 54.93, H 3.92;
found C 54.86, H 3.78.
Supporting Information (see footnote on the first page of this
article): Computational details for compound 1.
cis-17: 55 %. NMR (CDCl3, 30 °C): 1H NMR: δH = 2.33 (s, 6 H, CH3),
7.18 (m, 8 H, m-Ph), 7.28 (m, 2 H, C4H), 7.35 (m, 2 H, C5H), 7.37 (m,
4 H, p-Ph), 7.51 (m, 8 H, o-Ph), 8.06 (br. s, 2 H, C2H), 8.17 (d, JHH
=
3
Acknowledgments
7.6 Hz, 2 H, C6H) ppm; 13C{1H} NMR: δC = 21.5 (s, CH3), 125.4 (d,
JPC = 58 Hz, i-Ph), 127.4 (d, JPC = 40 Hz, C1), 128.3 (s, C5H), 128.4 (d,
JPC = 10 Hz, m-Ph), 130.0 (s, C6H), 131.3 (s, C2H), 131.8 (s, p-Ph),
134.6 (s, C4H), 135.8 (d, JPC = 10, JPtC = 8 Hz, o-Ph), 138.3 (s, C3),
We thank the Royal Society and the Leverhulme Trust (F/00 230/
AL, studentship to A. J. S.) for financial support. I. R. C. gratefully
acknowledges the award of a Royal Society University Research
Fellowship.
195.1 [d, JPC = 41 Hz, C(O)P] ppm; 31P{1H} NMR: δP = 14.8 (s, JPtP
=
3505 Hz) ppm; 195Pt{1H} NMR: δPt = –4351 (t, 1JPtP = 3505 Hz) ppm.
trans-17: 45 %. NMR (CDCl3, 30 °C): 1H NMR: δH = 2.33 (s, 6 H, CH3),
Keywords: Phosphane ligands · Phosphanes · Transition
metals · Phosphomides · Coordination compounds
7.27 (m, 2 H, C5H), 7.36 (m, 8 H, m-Ph), 7.36 (m, 2 H, C4H), 7.45 (m,
3
4 H, p-Ph), 7.77 (dt, JHH = 6.2, JPH = 5.8 Hz, 8 H, o-Ph), 8.16 (br. s, 2
3
H, C2H), 8.33 (d, JHH = 7.7 Hz, 2 H, C6H) ppm; 13C{1H} NMR: δC
=
21.5 (s, CH3), 126.6 (t, JPC = 27 Hz, i-Ph), 128.0 (br., C6H), 128.3 (s,
C5H), 128.5 (t, JPC = 6 Hz, m-Ph), 131.2 (br., C2H), 131.6 (s, p-Ph),
134.8 (s, C4H), 135.8 (t, JPC = 6 Hz, o-Ph), 137.4 (t, JPC = 23 Hz, C1),
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Eur. J. Inorg. Chem. 2016, 4076–4082
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Received: May 18, 2016
Published Online: August 9, 2016
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4082
© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim