Synthesis of [1′-(diphenylthiophosphoryl)ferrocenyl]ethyne and alkyne-metal complexes thereof

Article abstract of DOI:10.1016/j.jorganchem.2006.02.027

The novel functionalized ferrocene alkyne Ph₂P(S)fcC {triple bond, long}CH (1; fc = ferrocene-1,1′-diyl) was synthesized from Ph₂P(S)fcCHO (6) via the Corey-Fuchs reaction. It was further reacted with K₂[HgI₄]/K

Full text of DOI:10.1016/j.jorganchem.2006.02.027

Journal of Organometallic Chemistry 691 (2006) 2863–2871
www.elsevier.com/locate/jorganchem
Synthesis of [10-(diphenylthiophosphoryl)ferrocenyl]ethyne
and alkyne-metal complexes thereof
ˇ
*
ˇ
ˇ
´ ˇ
´
Petr Stepnicka , Ivana Cısarova
Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12840 Prague, Czech Republic
Received 27 October 2005; received in revised form 16 February 2006; accepted 20 February 2006
Available online 28 February 2006
Abstract
The novel functionalized ferrocene alkyne Ph2P(S)fcC„CH (1; fc = ferrocene-1,10-diyl) was synthesized from Ph2P(S)fcCHO (6) via
the Corey–Fuchs reaction. It was further reacted with K2[HgI4]/KOH to give mercury(II) acetylide Hg{C„CfcP(S)Ph2}2 (8), and with
[Co2(CO)8] to afford the trimetallic Co2Fe complex [(l-g2:g2-1){Co(CO)3}2](Co–Co) (9). All compounds were characterized by spectral
methods (IR, NMR, and MS) and by combustion or high-resolution MS elemental analyses. In addition, the crystal structures of 1,
Ph2PfcBr (5), 6, Ph2P(S)fcCH@CBr2 (7), and 9 were determined by single-crystal X-ray diffraction.
ꢀ 2006 Elsevier B.V. All rights reserved.
Keywords: Ferrocene; Alkyne; Phosphine sulfides; Synthesis; Mercury; Cobalt; Structure determination
1. Introduction
fc = ferrocene-1,10-diyl). This contribution deals with the
synthesis and coordination behaviour towards selected
metals of this ‘semi-masked’ phosphinoalkyne.
Ferrocene alkynes represent valuable ligands and build-
ing blocks for organometallic synthesis and material sci-
ence [1]. The area of their possible application can be
further widened by introducing one or more functional
groups into their molecules. For instance, functionalized
ferrocene alkynes have been utilized in the preparation of
redox-active organometallic oligo- and polymers [2,3] and
their precursors [4], and as precursors to materials with
non-linear optical properties [5] and nucleobase receptors
[6]. Besides, ferrocene alkynes modified with polar groups
hold great potential for the synthesis of other ferrocene
derivatives [7]. In view of these facts, it appears somewhat
surprising that there was only little effort devoted to the
synthesis of ferrocene alkynes substituted with standard
donor groups (e.g., N-donor groups and phosphines) and
their coordination behaviour [8]. In an effort to extend
the chemistry of ferrocene alkynes modified with poten-
tially coordinating groups, we decided to study [10-(diphe-
nylthiophosphoryl)ferrocenyl]ethyne, Ph2P(S)fcC„CH (1;
2. Results and discussion
2.1. Synthesis of the ligand 1
For the preparation of alkyne 1, we made use of the
known precursor 10-(diphenylphosphino)ferrocenecarb-
oxaldehyde (3). This compound, which was originally
prepared by stepwise metallation/functionalization of
1,10-bis(tributylstannyl)ferrocene [9], is more conveniently
obtained from ring-opening of 1-phenyl-[1]-phosphaferro-
cenophane (2) with phenyl lithium and quenching the lith-
iated intermediate with N,N-dimethylformamide (Scheme
1, route A) [10] or, alternatively, by sequential lithiation/
functionalization of 1,10-dibromoferrocene (route B) [11] .
Aldehyde 3 was reacted with elemental sulfur to give the
corresponding phosphine sulphide 6, which was subse-
quently converted to the desired alkyne 1 by applying the
Corey–Fuchs methodology [12] (Scheme 2). Aldehyde 6
was first reacted with CBr4/PPh3 mixture to give 10-(di-
phenylthiophosphoryl)-1-(2,2-dibromovinyl)ferrocene (7).
*
Corresponding author. Fax: +420 221 951 253.
ˇ
E-mail address: stepnic@natur.cuni.cz (P. Steˇpnicˇka).
0022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.02.027

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P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2864
route A
PPh
2
i.
ii.
Fe
Fe
PPh
CHO
C12
2
3
C11
Fe
v.
P1
C18
C6
Br
Br
PPh
Br
2
iv.
iii.
S1
Fe
Fe
C7
C17
Fe
C2
4
5
route B
Scheme 1. Synthetic routes to (phosphino)aldehyde 3. Legend: (i) 1. LiBu/
TMEDA, 2. PhPCl2. (ii) 1. LiPh, 2. Me2NCHO. (iii) 1. LiBu/TMEDA, 2.
1,2-C2F4Br2 (or C2Cl4Br2). (iv) 1. LiBu, 2. PhPCl2. (v) 1. LiBu, 2.
Me2NCHO; TMEDA = N,N,N0,N0-tetramethyl-1,2-diaminoethane.
C1
C23
C24
Fig. 1. View of molecule 1 in the structure of alkyne 1. Displacement
ellipsoids are shown at 30% probability level. Note. Atom-labelling scheme
for molecule 2 is similar: the respective atom labels are obtained by adding
30 the respective atom label in molecule 1. Selected geometric data;
molecule 1: Fe(1)–Cg(1) 1.6492(9), Fe(1)–Cg(2) 1.6394(9), P(1)–S(1)
1.9543(7), P(1)–C(6) 1.790(2), P(1)–C(11) 1.817(2), P(1)–C(17) 1.812(2),
S
PPh
PPh
2
2
S
8
Fe
Fe
˚
CHO
CHO
C(1)–C(23) 1.432(3), C(23)–C(24) 1.185(3) A, \Cp1,Cp2 2.2(1), C(1)–
C(23)–C(24) 176.2(2)ꢁ; molecule 2: Fe(2)–Cg(3) 1.6514(9), Fe(2)–Cg(4)
3
6
1.6406(9), P(2)–S(2) 1.9531(7), P(2)–C(36) 1.792(2), P(2)–C(41) 1.821(2),
˚
CBr /PPh
4
P(2)–C(47) 1.812(2), C(31)–C(53) 1.431(3), C(53)–C(54) 1.181(3) A,
3
\Cp3,Cp4 0.5(1), C(31)–C(53)–C(54) 175.6(2)ꢁ. Definition of the ring
planes: Cp1: C(1–5), Cp2; C(6–10); C(31–35), Cp2; C(36–40); Cg(1–4) are
the respective ring centroids.
S
S
PPh
PPh
2
2
i. LiBu
Fe
Fe
the asymmetric unit. In both cases, however, the indepen-
dent molecules are practically identical, showing only
minor conformational differences in the pairs (1 in the con-
formation of the ferrocene unit and the phosphorus substi-
tuent while 6 only very slightly in the orientation of the
phenyl rings) [13].
Br
+
ii. H
C
C
C
H
C
Br
H
1
7
Scheme 2. The synthesis of alkyne 1.
The structures corroborate the expected structures and
their geometric parameters compare favourably with those
in the related, structurally characterized compounds [14].
For instance, the geometry of the alkynyl moiety in 1
corresponds nicely to that in (ethynyl)ferrocene [15], the
C–Br bond length in 5 is very similar to those in, e.g., 1-
A subsequent eliminative dehalogenation of the latter com-
pound with butyl lithium followed by aqueous work-up
and crystallization gave alkyne 1 as an air-stable, orange
crystalline solid in 60% overall yield with respect to 3.
All new compounds were characterized by standard
spectral methods (NMR, IR, and MS) and gave correct ele-
mental analyses. In addition, the solid-state structures of 1
and 5–7 were determined by single-crystal X-diffraction
analysis.
0
˚
bromo-1 -(2-chloroethen-1-yl)ferrocene (1.887 A [16]) and
0
˚
1,1 -dibromoferrocene (1.866 and 1.882 A [17]), whereas
the molecular structure of aldehyde 6 differs only marginally
˚
from that of its phosphane precursor 3 (C@O 1.213 A).
Notably, the carbonyl group in 6 is twisted from a position
coplanar with its parent cyclopentadienyl ring, the devia-
tion from the cyclopentadienyl plane being higher for the
carbonyl carbon than for the oxygen atom (cf. perpendicu-
lar distances from the least-squares cyclopentadienyl
2.2. Crystal structures of 1 and 5–7
Views of the molecular structures of 1 and 5-7 are shown
in Figs. 1–4 together with the relevant geometric data.
Compounds 1 and 6 crystallize with two molecules within
˚
planes; molecule 1: C(23) 0.105(2) and O(1) 0.042(2) A;

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P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2865
C12
C11
C17
P1
C2
C1
C2
S1
Fe
C18
C1
C23
Fig. 2. Molecular structure of 5. Displacement ellipsoids are scaled to the
30% probability level. Selected geometric data: Fe–Cg(1) 1.647(2), Fe–
Cg(2) 1.642(2), C(1)–Br 1.883(4), P–C(6) 1.813(4), P–C(11) 1.833(4), P–
O1
Fig. 3. A view of molecule 1 in the structure of 6 showing displacement
ellipsoids with 30% probability. Molecule 2 is practically identical; atom
labels for molecule 2 are obtained by adding 30 to the respective atom
label in molecule 1 (except for Fe(2), P(2), and S(2)). Selected geometric
data; molecule 1: Fe(1)–Cg(1) 1.6530(9), Fe(1)–Cg(2) 1.6450(9), P(1)–S(1)
1.9506(7), P(1)–C(6) 1.793(2), P(1)–C(11) 1.816(2), P(1)–C(17) 1.818(2),
C(1)–C(23) 1.452(3), C(23)–O(1) 1.217(3) A, \Cp1,Cp2 2.2(1), C(1)–
C(23)–O(1) 124.1(2)ꢁ; molecule 2: Fe(2)–Cg(3) 1.6474(9), Fe(2)–Cg(4)
1.6485(9), P(2)–S(2) 1.9474(7), P(2)–C(36) 1.792(2), P(2)–C(41) 1.811(2),
P(2)–C(47) 1.818(2), C(31)–C(53) 1.453(3), C(53)–O(2) 1.216(3) A,
\Cp3,Cp4 3.1(1), C(31)–C(53)–O(2) 125.4(2)ꢁ (the ring planes are defined
as for 1, see Fig. 1).
˚
C(17) 1.839(4) A; \Cp1,Cp2 0.6(2)ꢁ (the ring planes are defined as for 1,
see Fig. 1).
˚
molecule 2: C(53) ꢀ0.116(2) and O(2) ꢀ0.025(2) A). Like-
wise, the dibromovinyl group in 7 is rotated with respect
to the adjacent cyclopentadienyl ring at the dihedral angle
of the {C(23)C(24)Br(1)Br(2)} and Cp1 least-square planes
of 29.6(2)ꢁ. However, the dibromovinyl group itself is
almost perfectly planar and its overall geometry matches
that in 1,1-dibromo-2-[3,5-bis(benzyloxy)phenyl]ethene [18].
A noteworthy feature of the whole series is the similarity
of the overall molecular arrangement (Scheme 3). Ferrocene
units in all molecules (1, 5–7) show well balanced Fe–
Cg(1,2) distances (relative differences are lower than 1%)
and negligible tilts of the cyclopentadienyl rings (cf. the
maximum tilt angle of 3.1ꢁ for 6, molecule 2). As indicated
by the torsion angle C(1)–Cg(1)–Cg(2)–C(6) (s), all com-
pounds adopt similar conformations at the ferrocene unit;
1: s = 78.5(2)ꢁ and ꢀ73.7(1)ꢁ (two independent molecules),
5: s = 70.7(3)ꢁ, 6: s =ꢀ 75.0(1)ꢁ and 77.3(1)ꢁ (two symmet-
rically non-equivalent molecules), and 7: s = 66.0(2)ꢁ. The s
angles are scattered around the value characteristic for the
ideal syn-eclipsed conformation (s = 72ꢁ). In addition, all
compounds have similarly oriented phosphorus groups.
The Ph2P(S) moieties, where E is sulfur atom (1, 6, and 7)
or lone electron pair (5), are oriented so that one phenyl ring
is directed outwards the ferrocene unit with the pivotal
C(fc)–C(Ph1) bond practically parallel to the axis of the fer-
rocene framework whilst the E-substituent and the other
phenyl ring point towards it with the ferrocene axis approx-
imately bisecting the E–P–C(Ph2) angle. Moreover, the sec-
ond substituent at the ferrocene unit (X = C„CH, Br,
CHO, and CH@CBr2) is always located at the side of the
phenyl group. Such an arrangement leads to relatively com-
˚
˚
pact (though perhaps sterically congested) structures and
my thus facilitate the crystal assembly that, due to a lack
of stronger intermolecular interactions, seems to be dictated
largely by dipolar interactions and intermolecular forces at
the van der Waals level (with occasional support from the
weak hydrogen bonds, e.g., C–Hꢁ ꢁ ꢁS/O).
2.3. Preparation of complexes
Similarly to simple alkynes [19], ethanol–acetone solu-
tion of alkyne 1 reacts smoothly with alkalic solution of
potassium tetraiodomercurate(II) to give the appropriate
mercury(II) acetylide 8 in good yield (Scheme 4). Unfortu-
nately, the crystallized acetylide is only sparingly soluble in
common organic solvents which makes it impractical for
further synthetic utilization.
The compound was characterized by spectral methods
and elemental analysis. Its NMR spectra are in accordance
with the formulation, showing signals due Ph2P(S)-substi-
tuted ferrocene framework. The r-coordination of the tri-
ple bond is clearly reflected by an absence of the signal due
to the terminal „CH group (1H NMR), and further by
changes in the region of triple bond C-13 resonances:

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P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2866
whereas the Cb is influenced only marginally, the „CH res-
onance is replaced with a signal of the mercury-bonded car-
bon (Ca) at lower field. In IR spectrum, the m(C„C)
stretching vibration of 8 appears as a composite band,
shifted by around 50 cmꢀ1 to higher energies as compared
with the parent alkyne.
Alkyne 1 also reacted smoothly with one-molar equiva-
lent of [Co2(CO)8] in benzene at room temperature to give
(l-alkyne)hexacarbonyldicobalt complex 9 as a brown
dichroic crystalline solid in a 88% yield after chromato-
graphic purification (Scheme 5). A comparison of the spec-
tral data (NMR and IR) obtained for 9 with those reported
for similar complexes [20] as well as identical dP values for 1
and 8 indicate that even in this case the phosphine sulphide
1
moiety remains uncoordinated. The CH[Co] signal in H
NMR spectrum of 8 appears at dH 6.03 (cf. dH 6.27 for
the analogue without the phosphorus substituent, [(l-
g2:g2-FcCCH){Co(CO)3}2](Co–Co) (10) [20a]), while the
CO resonance in 13C NMR spectrum is observed at a
slightly higher field as compared to the same reference
compound (dC 199 and 203, respectively [20e]). The FAB
mass spectrum of 9 shows the molecular ion ([M+H]+)
and fragments resulting from successive loss of the car-
bonyl ligands.
Crystallization of 9 from toluene to hexane gave single
crystals suitable for X-ray diffraction analysis. The molec-
ular structure is depicted in Fig. 5 and the relevant geomet-
ric parameters are given in Table 1. The geometry of the
alkyne-bridged Co2(CO)6 moiety in 9 compares favourably
with those in other structurally characterized dicobalt
hexacarbonyl complexes featuring ferrocene alkynes
[20b,20d,20e], particularly, with 10 [21].
Fig. 4. Molecular structure of 7 showing the displacement ellipsoids at the
30% probability level. Selected geometric data: Fe–Cg(1) 1.649(2), Fe–
Cg(2) 1.641(2), C(24)–Br(1) 1.891(3), C(24)–Br(2) 1.893(3), P–S 1.955(1),
P–C(6) 1.788(3), P–C(11) 1.819(3), P–C(17) 1.812(3), C(1)–C(23) 1.460(4),
C(23)–C(24) 1.322(4) A; \Cp1,Cp2 1.6(2), C(1)–C(23)–C(24) 129.0(3),
C(23)–C(24)–Br(1) 120.9(2), C(23)–C(24)–Br(2) 124.9(2), Br(1)–C(24)–
˚
Br(2) 114.2(2)ꢁ (for the definition of the ring planes see Fig. 1).
The coordination of 1 leads to an elongation of the triple
bond, consistent with donation from bonding p-electron
systems. Furthermore, the loss of triple bond character
and rehybridization is reflected by the bond lengths and
angles at the vertexes of the dicobaltatetrahedrane (Table
1; see also the torsion angle C(1)–C(23)–C(24)–H(24) of
ꢀ15(3)ꢁ). The Co2C2 core is slightly asymmetric (less than
in 10), showing somewhat varying Co–C bond lengths (the
Co(2)–C(23) bond is by ca. 0.04 A shorter that the remain-
ing three bonds).
The ferrocene unit in 9 is rotated with respect to the
Co2C2 framework so that the dihedral angle subtended
by the {Co(1), C(23), C(24)} and {Co(1), C(23), C(24)}
planes and the Cp1 ring (see Fig. 5) are 14.9(2)ꢁ and
E
P
P
E
Fe
X
Fe
X
˚
Scheme 3. A schematic drawing of the molecular conformation adopted
by 1 and 5–7 in the solid state as viewed along (left) and perpendicular
(right) to the axis of the ferrocene unit.
P(S)Ph
2
Fe
P(S)Ph
2
C
C
1 + K [HgI ]
2
4
Hg
C
- KI, -HI
Fe
C
[Co (CO) ] + 1
2 8
- CO
H
C
C
Fe
(OC) Co
3
Co(CO)
Ph P(S)
2
3
8
9
Scheme 4.
Scheme 5.

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P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2867
C(12)
C(11)
C(6)
P
S
C(7)
C(18)
Fe
C(17)
O(1)
C(2)
C(31)
C(1)
C(23)
C(33)
O(3)
Co(1)
C(24)
C(32)
O(2)
Co(2)
O(4)
O(34)
C(36)
O(6)
C(35)
O(5)
Fig. 5. Molecular structure of 9. Displacement ellipsoids are scaled to the 30% probability level.
Table 1
a
˚
Selected distances and angles for 9 (in A and ꢁ)
Co(1)–Co(2)
Co(1)–C(23)
Co(2)–C(23)
Co(1)–C(24)
Co(2)–C(24)
Co–C
C„O
Co–C„O
Co(1)–Co(2)–C(23)
C(23)–Co(1)–C(24)
Co(1)–Co(2)–C(24)
Co(1)–C(23)–Co(2)
Co(1)–C(23)–C(24)
Co(1)–C(24)–C(23)
C(1)–C(23)–C(24)
C(23)–C(24)–H(24)
2.4633(6)
1.956(2)
1.994(2)
1.955(3)
C(23)–C(24)
C(24)–H(24)
C(1)–C(23)
P–S
P–Cb
Fe–Cg(1)
Fe–Cg(2)
\Cp1,Cp2
1.332(4)
0.99(3)
1.446(3)
1.9537(9)
1.794(3)–1.822(3)
1.653(1)
1.648(1)
3.8(1)
52.11(7)
39.5(1)
50.79(9)
78.2(1)
72.1(2)
68.5(2)
112.23(8)–115.44(8)
103.6(1)–106.26(1)
1.950(3)
1.784(5)–1.823(4)
1.129(7)–1.141(4)
176.7(3)–178.3(3)
50.72(7)
39.8(1)
50.98(8)
77.17(9)
70.1(2)
70.1(2)
145.5(3)
Co(2)–Co(1)–C(23)
C(23)–Co(2)–C(24)
Co(2)–Co(1)–C(24)
Co(1)–C(24)–Co(2)
Co(2)–C(24)–C(23)
Co(2)–C(23)–C(24)
S–P–C(6,11,17)
C–P–Cc
144(2)
a
Least-squares planes are defined as for 1. See caption to Fig. 1.
The range of P–C(6,11,17) bond lengths.
The range of C(6)–P–C(11,17) and C(11)–P–C(17) angles.
b
c
80.5(2)ꢁ, respectively. Likewise, the C(23)–C(24) bond devi-
ates from coplanarity with Cp1, intersecting the cyclopen-
tadienyl plane at an angle of 14.5(2)ꢁ. The conformation
of the disubstituted ferrocene moiety is close to syn-eclipsed
conformation (s = ꢀ83.7(2)ꢁ), similar to 1 and the com-
pounds mentioned above. However, even in 9, there seems
to be no steric congestion between the proximal, bulky sub-
stituents at the ferrocene skeleton.

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2868
3. Conclusions
431 (27), 430 (M+ꢀ, 94), 402 ([MꢀCO]+, 25), 338 (22), 337
([MꢀC5H4CHO]+, 100), 273 (10), 197 (5), 183 (9), 170 (9),
121 ([C5H5Fe]+, 5), 56 (Fe, 8). IR (Nujol): m/cmꢀ1m(C@O)
1679 (vs), 1661 (s); 1242 (s), 1172 (s), 1104 (s), 1032 (m),
1028 (m), 842 (s), 758 (s), 719 (vs), 696 (s), 657 (vs), 542
(s), 499 (s), 490 (s). Anal. Calc. for C23H19FeOPS
(430.29): C, 64.20; H, 4.45. Found: C, 64.03; H, 4.70%.
Compound 1, a new functionalized organometallic
alkyne, was obtained in a good yield by conventional meth-
ods from Ph2PfcCHO. Although its donor properties have
been tested thus far only in r-acetylide complex 8 and p-
alkyne-bridged dicobalt carbonyl complex 9, it is apparent
that the presence of a relatively weakly coordinating thios-
phosphoryl group (as compared to the corresponding
phosphine) enables this compound to coordinate rather
as a simple alkyne than a heterobifunctional donor.
4.3. Synthesis of Ph2P(S)fcCH@CBr2 (7)
A solution of tetrabromomethane (3.33 g, 10 mmol in
10 mL of dichloromethane) was introduced slowly to an
ice-cooled solution of aldehyde 6 (2.16 g, 5.0 mmol) and
triphenylphosphane (5.25 g, 20 mmol) in dry dichlorometh-
ane (40 mL) with stirring. After the addition was com-
pleted (ca. 3 min), stirring was continued for another
20 min at 0 ꢁC. The reaction was terminated by adding a
mixture of saturated aqueous NaHCO3 solution (20 mL)
and 30% hydrogen peroxide (3 mL) and stirring for
15 min. The organic layer was separated, washed with
10% aqueous Na2S2O3 to remove unreacted hydrogen per-
oxide, and dried over MgSO4. The solution was mixed with
alumina (grade for chromatography, Brockmann) and the
mixture evaporated under reduced pressure (pre-adsorption).
The solid was transferred onto a top of a short alumina col-
umn and eluted with diethyl ether (Note. Large amounts of
the solvent are necessary for complete elution of the prod-
uct which is only sparingly soluble in ether; triphenylph-
oshane oxide co-elutes). The yellow eluate was
evaporated to dryness, taken up in chloroform (ca.
50 mL) and the solution evaporated again to leave a dark
brown oil, which was immediately crystallized by addition
of hot methanol (ca. 30 mL). The mixture was allowed to
stand at 0 ꢁC overnight, the separated product was filtered
off, washed with methanol and dried under vacuum. Yield
of 7: 2.45 g (83%), orange crystalline solid.
4. Experimental
4.1. Materials and methods
Unless noted otherwise, the syntheses were performed
under argon atmosphere and with an exclusion of the direct
day light. Tetrahydrofuran (THF) was distilled from potas-
sium-benzophenone ketyl. Toluene, diethyl ether and hex-
ane were dried over potassium metal and distilled.
Dichloromethane was dried with anhydrous potassium car-
bonate or distilled from calcium hydride. Other chemicals
and solvents were used as received from commercial suppli-
ers (Fluka, Aldrich; solvents from Lachema).
NMR spectra were measured on a Varian UNITY
Inova 400 spectrometer (1H, 399.95; 13C, 100.58; 31P, and
161.90 MHz) at 298 K. Chemical shifts (d/ppm) are given
relative to an internal tetramethylsilane (1H and 13C) or
an external 85% aqueous H3PO4 (31P). IR spectra were
recorded on an FT IR Nicolet Magna 760 instrument in
the range of 400-4000 cmꢀ1. Melting points were deter-
mined on a Kofler apparatus and are uncorrected.
4.2. Synthesis of Ph2P(S)fcCHO (6)
A mixture of aldehyde 3 (1.99 g, 5.0 mmol) and sulfur
(0.19 g, 6.0 mmol) in toluene (50 ml) was gently refluxed
for 1 h. The solids dissolved to give a clear solution, which
was filtered while hot and crystallized at ꢀ18 ꢁC. The crys-
talline product was filtered off, washed thoroughly with
hexane and dried in air. Evaporation of the mother liquor
and crystallization from hot toluene followed by isolation
as given above gave a second crop of 6. Combined yield:
1.91 g (89%), red brown flakes.
M.p. dec. above 155 ꢁC. 1H NMR (CDCl3): d 4.31
(apparent t, 2H), 4.43 (apparet q, 2H), 4.54 (apparet q,
2H), 4.65 (apparent t, 2H) (4· CH of fc); 6.78 (s, 1H,
CH@), 7.38–7.77 (m, 10H, PPh2). 13C{1H} NMR (CDCl3):
d
70.80, 71.33, 73.23 (d, JPC = 10 Hz), 74.10 (d,
1
JPC = 13 Hz) (4· CH, fc); 76.06 (d, JPC = 95 Hz, C–P of
fc), 81.01 (C–CH@, fc), 85.01 (@CBr2), 128.28 (d,
JPC = 13 Hz), 131.37 (d, JPC = 3 Hz), 131.58 (d,
1
JPC = 11 Hz) (3· CH, Ph); 134.27 (d, JPC = 87 Hz, Cipso
,
M.p. 184–185 ꢁC (ethyl acetate–hexane). 1H NMR
(CDCl3): d 4.54 (apparent q, 2H), 4.58–4.61 (m, 4H),
4.80 (apparent t, 2H) (4· CH of fc); 7.38–7.76 (m, 10H,
PPh2), 9.62 (s, 1H, CHO). 13C{1H} NMR (CDCl3): d
71.36, 73.24 (d, JPC = 10 Hz), 74.18 (d, JPC = 12 Hz),
Ph), 134.35 (@CH). 31P{1H} NMR (CDCl3): d = 41.6 (s).
EI MS: m/z (relative abundance) 588 (11), 586 (20) and
584 (11) (M+); 507 (49) and 505 (48) ([MꢀBr]+); 427 (14,
[Mꢀ2Br]+), 402 ([MꢀCHCBr2]+), 338 (22), 337
([MꢀC5H4CHCBr2]+, 100), 294 (14), 293 (14), 273 (12),
226 (11), 185 (16), 183 (35), 171 (16), 170 (18), 121 (11),
89 (14), 56 (10). IR (Nujol): m/cmꢀ1 1735 (m), 1173 (s),
1103 (s), 1036 (m), 841 (m), 825 (s), 760 (m), 715 (vs),
700 (m), 654 (vs), 542 (m), 501 (s), 488 (vs). Anal. Calc.
for C24H19Br2FePS (589.11): C, 49.18; H, 3.27. Found:
C, 48.89; H, 3.15%.
1
75.04 (4· CH of fc); ca. 77.49 (d, JPC ꢂ 95 Hz, C–P of
fc; the signal is obscured by the solvent resonance), 80.03
(C-CHO, fc), 128.40 (d, JPC = 13 Hz), 131.54 (d,
JPC = 3 Hz), 131.56 (d, JPC = 10 Hz) (3· CH, Ph); 133.85
1
(d, JPC = 87 Hz, Cipso, Ph), 193.55 (CHO). 31P{1H}
NMR (CDCl3): d 40.9 (s). EI MS: m/z (relative abundance)

ˇ
P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2869
4.4. Synthesis of Ph2P(S)fcCBCH (1)
with chloroform (20 mL). The filtered orange extract was
allowed to crystallize by diffusion of hexane vapours over
several days. The solid product formed was filtered off,
washed with hexane and dried under vacuum. Yield of 8:
76 mg (72%), rusty orange microcrystalline solid. Note.
The recrystallized product is only very poorly soluble in
all common organic solvents (CH2Cl2, CHCl3, acetone,
methanol, etc.)
Butyl lithium in hexanes (4 mL 2.5 M, 10 mmol) was
added to a solution of 7 (2.35 g, 4.0 mmol) in dry THF
(40 mL) with stirring and cooling to ꢀ78 ꢁC. The mixture
was stirred for 1 h at ꢀ78 ꢁC and then for 1 h with the
cooling bath removed. The reaction mixture was
quenched by addition of saturated aqueous NH4Cl solu-
tion and diluted with diethyl ether. Organic layer was sep-
arated, washed with the NH4Cl solution and then dried
over magnesium sulfate. The solvents were removed under
reduced pressure yielding a rusty orange residue, which
was extracted with hot ethyl acetate (100 mL). The extract
was filtered and diluted with hexane (100 mL). A subse-
quent crystallization at ꢀ18 ꢁC gave 1 as orange needles,
which were filtered off, washed with hexane and dried
under vacuum. The mother liquor was evaporated and
the residue crystallized in a similar manner (20 mL of
each solvent) providing a second fraction of the product.
Combined yield: 1.40 g (82%). The compound thus
obtained tends to retain traces of ethyl acetate. The pres-
ence of the solvent in the bulk material was shown by IR
and NMR spectra.
1H NMR (CDCl3): d 4.28 (apparent t, 2 H), 4.44–4.48
(m, 4H), 4.55 (apparent q, 2H) (4· CH of fc); 7.391–7.76
(m, 10H, PPh2). 13C{1H} NMR (CDCl3): d 65.60 (C„C),
71.35, 73.65, 74.72, 74.83 (d, JPC = 3 Hz) (4· CH, fc);
103.88, 117.97 (C„C and C–C„C of fc), 128.30 (d,
JPC = 12 Hz), 131.29 (d, JPC = 3 Hz), 131.72 (d,
1
JPC = 11 Hz) (3· CH, Ph); 134.45 (d, JPC = 87 Hz, Cipso
,
Ph); the C–P signal at fc is obscured by the solvent
resonance. 31P{1H} NMR (CDCl3): d +41.7 (s). FAB
MS: m/z 1052 (M+), 426 ([Ph2P(S)fcC„CH]+). IR (Nujol):
m/cmꢀ1m(C„C) 2163 (vw), 2147 (w), 2122 (vw); 1306 (m),
1167 (s), 1101 (s), 1034 (m), 1023 (m), 997 (w), 920 (m),
845 (m), 831 (m), 760 (m), 746 (m), 712 (vs), 694 (s), 649
(vs), 627 (m), 614 (m), 541 (s), 486 (s), 467 (s), 435 (s). Anal.
Calc. for C3H3Fe2HgP2S2 Æ 0.3 CHCl3: C, 53.37; H, 3.37.
Found: C, 53.39; H, 3.40%.
1H NMR (CDCl3): d 2.62 (s, 1H, „CH), 4.27 (apparent
t, 2H), 4.42 (apparent t, 2H), 4.48 (apparent q, 2H), 4.54
(apparent q, 2H) (4· CH of fc); 7.38–7.46 (m, 10 H,
PPh2). 13C{1H} NMR (CDCl3): d 65.38 (C„CH), 71.37,
73.28, 74.35 (d, JPC = 12 Hz) (3· CH, fc); 74.45 („CH),
4.6. Synthesis of [Co2(CO)6(l-g2:g2-1)] (9)
1
74.84 (d, JPC = 10 Hz, CH, fc) 76.20 (d, JPC = 98 Hz, C–
Dicobalt octacarbonyl (70 mg, 0.20 mmol) and 1
P of fc), 81.15 (C–C„CH, fc), 128.24 (d, JPC = 12 Hz),
131.26 (d, JPC = 3 Hz), 131.60 (d, JPC = 11 Hz) (3· CH,
(87 mg, 0.20 mmol) were dissolved in benzene (5 mL) and
the reaction mixture was stirred overnight at room temper-
ature. The volume of the reaction solution was reduced
under vacuum to ca. 2 mL and the residue transferred onto
a top of a chromatographic column filled with silica gel in
diethyl ether–hexane (1:2). Eluting with the same solvent
mixture provided firstly a minor band containing traces
of unreacted alkyne, and then major, brownish band of
the product. The latter was collected and evaporated to
give 9 as a brown microcrystalline solid showing green-
red dichroism (126 mg, 88%).
1
Ph); 134.29 (d, JPC = 87 Hz, Cipso, Ph). 31P{1H} NMR
(CDCl3): d +41.7 (s). EI-MS: m/z (relative abundance)
428 (8), 427 (23), 426 (M+ꢀ, 82), 337 ([Ph2P(S)C5H4Fe]+,
100), 335 (5), 237 (11), 226 (9), 197 (6), 183 (11), 171 (9),
170 (11), 56 (Fe+, 11). IR (Nujol): m/cmꢀ1 alkyne m(CH)
3290 (w); *3218 (w), m(C„C) 2105 (w); *m(C@O) 1733
(m), 1307 (m), 1194 (m), 1169 (s), 1154 (m), 1102 (s),
*1035 (s), 1027 (s), 914 (m), 840 (s), 819 (s), 753 (s), 178
(vs), 694 (vs), 656 (vs), 627 (m), 614 (m), 566 (m), 543 (s),
526 (vs), 494 (vs), 482 (s), 448 (m), 435 (m); signals labelled
with an asterisk are attributable to the residual ethyl ace-
1H NMR (CDCl3): d 4.31, 4.34 (2· apparent t, 2H),
4.38, 4.48 (2· apparent q, 2H) (4· CH of fc); 6.03 (s, 1H,
CH[Co]), 7.41–7.77 (m, 10H, PPh2). 13C{1H} NMR
(CDCl3): d 71.32, 71.89, 73.82 (d, JPC = 10 Hz), 74.46 (d,
JPC = 12 Hz) (4· CH, fc); 75.72 (CH[Co]), 86.25 (C–
CC[Co] of fc), 88.98 (C[Co]), 128.30 (d, JPC = 13 Hz),
131.31 (d, JPC = 3 Hz), 131.65 (d, JPC = 11 Hz) (3· CH,
1
3
tate. Anal. Calc. for C24H19FePS ꢁ CH3CO2Et: C, 67.78;
H, 4.79. Found: C, 67.80; H, 4.69%. HR MS (EI): Calc.
for C24H1956FePS: 426.0295, found 426.0311.
1
4.5. Synthesis of Hg{CCfcP(S)Ph2}2 (8)
Ph); 134.43 (d, JPC = 87 Hz, Cipso, Ph), 199.44 (br, CO);
the C–P signal at fc probably coincides with the solvent res-
onance. 31P{1H} NMR (CDCl3): d +41.7 (s). FAB MS:
m/z 713 ([M+H]+), 657 ([M+Hꢀ2CO]+), 628 ([Mꢀ3CO]+),
572 ([Mꢀ5CO]+), 544 ([Mꢀ6CO]+). IR (Nujol):
m/cmꢀ1 m(C„O) 2091 (vs), 2055 (vs), 2033 (vs), 2010
(vs), 1996 (vs); 1170 (m), 1099 (m), 1034 (w), 1026 (m),
826 (m), 752 (m), 716 (s), 694 (s), 656 (s), 512 (s), 490 (s),
455 (m). HR MS Calc. for C30H20Co256FeO6PS
([M+H]+): 712.8732. Found: 712.8752.
Mercury(II) chloride (68 mg, 0.25 mmol) and KI
(249 mg, 1.5 mmol) were suspended in 5% aqueous KOH
(5 mL) and the mixture was stirred until all solids dis-
solved. Then, a hot solution of 1 (85.5 mg, 0.20 mmol) in
ethanol–acetone (1:1, 12 mL) was added, causing an imme-
diate formation of an ochre precipitate. The mixture was
stirred at room temperature for 30 min, the precipitated
solid was filtered off, dried (at 60 ꢁC in air) and extracted

ˇ
P. Steˇpnicˇka, I. Cı´sarˇova´ / Journal of Organometallic Chemistry 691 (2006) 2863–2871
2870
Table 2
Crystallographic data, data collection and structure refinement parameters for 1, 5, 6, 7 and 9
Compound
1
5
6
7
9
Formula
M (g molꢀ1
C24H19FePS
426.27
C22H18BrFeP
449.09
C23H19FeOPS
430.26
C24H19Br2FePS
586.09
C30H19Co2FeO6PS
712.19
)
Crystal system
Space group
Monoclinic
P21/n (no. 14)
13.2162(2)
17.3084(3)
17.2149(3)
Monoclinic
P21/c (no. 14)
8.7250(2)
17.0619(5)
13.1367(3)
Monoclinic
P21/n (no. 14)
13.3420(1)
17.4117(2)
17.0096(2)
Monoclinic
P21/c (no. 14)
13.0769(2)
9.3115(1)
Triclinic
ꢀ
P1 ðno. 2Þ
˚
a (A)
7.5876(2)
8.8658(2)
22.0057(5)
97.941(2)
95.305(2)
98.614(1)
1439.88(6)
2
˚
b (A)
˚
c (A)
18.2543(3)
a (ꢁ)
b (ꢁ)
c (ꢁ)
101.901(1)
108.136(2)
102.0403(5)
101.9585(6)
3
˚
V (A )
3853.3(1)
8
1.470
0.980
0.664–0.960
66940
1858.44(8)
4
1.605
3.049
0.526–0.652
34315
3864.52(7)
8
2174.51(5)
4
1.790
4.547
0.355–0.454
29273
Z
D (g mLꢀ1
)
1.479
0.981
1.643
1.806
0.664–0.939
27361
6615/5162
4.10
l(Mo Ka) (mmꢀ1
Ta
)
e
–
Diffrns total
54363
8868/7073
3.60
Unique/obsdb diffrns
Rint (%)c
8778/6886
5.26
4264/3236
5.53
4967/4639
4.24
No. of params
487
3.22
4.81, 8.56
0.42, ꢀ0.44
287289
226
4.07
6.17, 10.56
0.66, ꢀ0.80
287286
487
3.22
4.65, 9.76
0.39, ꢀ0.50
287287
262
3.32
3.66, 785
0.46, ꢀ0.54
287288
374
3.53
5.52, 8.34
0.42, ꢀ0.83
287290
R obsd diffrns (%)d
R, wR all data (%)d
ꢀ3
˚
Dq (e A
)
CCDC ref. no.
a
The range of transmission coefficients.
b
c
Diffractions with Io > 2r(Io).
P
P
Rint
¼
j F o2 ꢀ F o2ðmeanÞ j = F 2o; where F 2oðmeanÞ is the average intensity for symmetry equivalent diffractions.
P
P
P
P
2
2 1=2
d
e
R = jFoj ꢀ jFcj/j jFoj, wR ¼ ½ fwðF 2o ꢀ F c2Þ g= wðF o2Þ ꢃ
.
Not corrected.
4.7. X-ray crystallography
matic CH groups, and CHO), 0.97 (methylene) and 0.96
(methyl) A] and assigned Uiso(H) = 1.2 Ueq(C). Final geo-
˚
Single crystals suitable for X-ray diffraction analysis
were selected directly from the reaction batch (1: orange
plate, 0.03 · 0.30 · 0.50 mm3) or obtained by recrystalliza-
tion of the bulk material from diethyl ether-hexane (5:
orange brown prism, 0.15 · 0.20 · 0.25 mm3), ethylace-
tate–hexane (6: red brown prism, 0.13 · 0.25 · 0.40 mm3;
7: rusty brown prism, 0.23 · 0.28 · 0.28 mm3) and from
toluene–hexane (9: brown plate, 0.03 · 0.15 · 0.25 mm3).
metric calculations were carried out with a recent version
of PLATON program [26].
Crystallographic data (excluding structure factors) have
been deposited with CCDC (see Table 2 for the deposition
numbers). These data can be obtained upon request from
the Cambridge Crystallographic Data Centre, 12 Union
Road, Cambridge CB2 1EZ, UK, e-mail: deposit@ccdc.
cam.ac.uk, or via the internet at www.ccdc.cam.ac.uk.
Full-set diffraction data ( h
k
l, 2h 6 55ꢁ) were col-
lected on a Nonius Kappa CCD diffractometer equipped
with Cryostream Cooler (Oxford Cryosystems) at
150(2) K using graphite monochromatized Mo Ka radia-
Acknowledgement
The authors thank the Grant Agency of the Czech
Republic (Grant No. 203/05/0276) for financial support.
˚
tion (k = 0.71073 A) and analyzed with the HKL program
package [22]. If appropriate, the data were corrected for
absorption by using an empirical multiscan method
(SORTAV routine [23]; 5 and 7) and gaussian correction pro-
cedure (1 and 9) included in the diffractometer software.
The structures were solved by direct methods (SIR-97
[24]) and subsequently refined by weighted full-matrix least
squares on F2 (SHELXL-97 [25]). The non-hydrogen atoms
were refined with anisotropic displacement parameters.
The H(24) atom in 9 was identified on the difference elec-
tron density map and its coordinates and isotropic dis-
placement parameter were refined without constraints.
All other hydrogen atoms were included in the calculated
positions [C–H bond lengths: 0.93 (alkene, alkyne and aro-
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ˇ
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