Reactions of a diacetylenic tetracobalt carbonyl complex with monophosphine triphenylphosphine or diphosphines

Article abstract of DOI:10.1016/j.poly.2014.01.034

Five new diacetylenic tetracobalt carbonyl complexes 2-6 with monophosphine or diphosphines have been prepared from the parent complex (μ-HCCCH ₂CH₂CH₂CH₂CCH-μ)[Co ₂(CO)₆]₂ (1), and their structures were fully characterized. Reaction of 1 with PPh₃ in the presence of Me ₃NO·2H₂O afforded (μ-HCCCH₂CH ₂CH₂CH₂CCH-μ)[Co₂(CO) ₅(PPh₃)]₂ (2) in 59% yield. Similarly, reaction of 1 with dppe (Ph₂PCH₂CH₂PPh₂) in the presence of Me₃NO·2H₂O gave (μ-HCCCH ₂CH₂CH₂CH₂CCH-μ)[Co ₂(CO)₅]₂(dppe) (3) and (μ-HCCCH ₂CH₂CH₂CH₂CCH-μ)[Co ₂(CO)₆][Co₂(CO)₄(dppe)] (4), with a bridging diphosphine ligand, in 20% and 16% yields, respectively, whereas (μ-HCCCH₂CH₂CH₂CH₂CCH-μ) [Co₂(CO)₅]₂(dppp) (dppp = Ph ₂PCH₂CH₂CH₂PPh₂) (5) and (μ-HCCCH₂CH₂CH₂CH₂CCH-μ) [Co₂(CO)₅]₂(dppb) (dppb = Ph ₂PCH₂CH₂CH₂CH₂PPh ₂) (6) were prepared by the reactions of 1 with dppp or dppb in the presence of Me₃NO·2H₂O in 29% and 36% yields, respectively. The new complexes 2-6 were characterized by elemental analysis, spectroscopy and, for 1-3 and 6, by X-ray crystallography. It is interesting to note that the X-ray crystal structures of 3 and 6 contain 12 and 14 atom macrocycles, respectively.

Full text of DOI:10.1016/j.poly.2014.01.034

Polyhedron 72 (2014) 66–71
Contents lists available at ScienceDirect
Polyhedron
journal homepage: www.elsevier.com/locate/poly
Reactions of a diacetylenic tetracobalt carbonyl complex
with monophosphine triphenylphosphine or diphosphines
⇑
Xu-Feng Liu
Department of Chemical Engineering, Ningbo University of Technology, Ningbo 315016, China
a r t i c l e i n f o
a b s t r a c t
Article history:
Five new diacetylenic tetracobalt carbonyl complexes 2–6 with monophosphine or diphosphines have
Received 28 November 2013
Accepted 27 January 2014
Available online 10 February 2014
been prepared from the parent complex (
structures were fully characterized. Reaction of 1 with PPh3 in the presence of Me3NOꢀ2H2O afforded
-HC„CCH2CH2CH2CH2C„CH- )[Co2(CO)5(PPh3)]2 (2) in 59% yield. Similarly, reaction of 1 with dppe
(Ph2PCH2CH2PPh2) in the presence of Me3NOꢀ2H2O gave ( -HC„CCH2CH2CH2CH2C„CH- )[Co2(CO)5]2
(dppe) (3) and ( -HC„CCH2CH2CH2CH2C„CH- )[Co2(CO)6][Co2(CO)4(dppe)] (4), with a bridging diphos-
phine ligand, in 20% and 16% yields, respectively, whereas -HC„CCH2CH2CH2CH2C„CH- )[Co2
(CO)5]2(dppp) (dppp = Ph2PCH2CH2CH2PPh2) (5) and -HC„CCH2CH2CH2CH2C„CH- )[Co2(CO)5]2
l-HC„CCH2CH2CH2CH2C„CH-l)[Co2(CO)6]2 (1), and their
(
l
l
l
l
Keywords:
l
l
Cobalt carbonyl complex
Phosphine ligand
Carbonyl substitution
Synthesis
(
l
l
(
l
l
(dppb) (dppb = Ph2PCH2CH2CH2CH2PPh2) (6) were prepared by the reactions of 1 with dppp or dppb in
the presence of Me3NOꢀ2H2O in 29% and 36% yields, respectively. The new complexes 2–6 were charac-
terized by elemental analysis, spectroscopy and, for 1–3 and 6, by X-ray crystallography. It is interesting
to note that the X-ray crystal structures of 3 and 6 contain 12 and 14 atom macrocycles, respectively.
Ó 2014 Elsevier Ltd. All rights reserved.
Crystal structure
1. Introduction
2. Experimental
The well known complexes (
l
-RC„CR0)Co2(CO)6 have been pre-
2.1. Materials and methods
pared by the reactions of Co2(CO)8 with alkynes since 1950s [1].
Studies on these cobalt carbonyl complexes, (
l
-RC„CR0)Co2(CO)6,
All reactions were performed using standard Schlenk and
vacuum-line techniques under N2 atmosphere. PPh3, dppe,
dppp, dppb and Me3NOꢀ2H2O were available commercially
and used as received. CH2Cl2 and MeCN were distilled over
CaH2 under N2. 1 [1] was prepared according to literature pro-
cedures. IR spectra were recorded on a Nicolet MAGNA 560
FTIR spectrometer. 1H, 31P anad 13C NMR spectra were ob-
tained on a Bruker Avance 500 MHz spectrometer. Elemental
analyses were performed with a Perkin-Elmer 240C analyzer,
while ESI-MS data were obtained on a Bruker Micro TOF Q-II
instrument.
have attracted a great deal of interest due to their applications in
organic syntheses [2], the Pauson–Khand reaction [3], the
protection of alkynes and the marking of acetylenic steroids [4].
Phosphine ligand substitution in (l
-RC„CR0)Co2(CO)6 has been
extensively studied in order to synthesize new complexes contain-
ing cobalt carbonyl [5–9]. The parent complex 1 was obtained by
the reaction of 1,7-octadiyne with Co2(CO)8 [1]. However, substitu-
tion reactions of 1 are relatively rare in the literature. As a contin-
uation of our previous work on carbonyl substitution reactions of
the transition metal carbonyl complexes [10–13], we have initiated
a study on the carbonyl substitution of 1 with a monophosphine or
diphosphines and have successfully prepared a series of cobalt
carbonyl complexes. In this paper, we will describe the synthesis
and characterization of cobalt carbonyl derivatives containing a
monophosphine or diphosphines via a carbonyl exchange reaction.
2.2. Characterization of 1
IR (KBr disk, cmꢁ1): mC
„
2093 (vs), 2049 (vs), 2028 (vs),
O
2005 (vs), 1995 (vs). 1H NMR (500 MHz, CDCl3, ppm): 6.09
(s, 2H, 2C„CH), 2.96 (s, 4H, 2CH„CCH2), 1.84 (s, 4H, CH„CCH2
CH2CH2CH2C„CH). 13C{1H} NMR (125 MHz, CDCl3, ppm):
199.88 (C„O), 96.72 (C„CH), 73.16 (C„CH), 33.90, 31.47 (2s,
CH2).
⇑
Tel./fax: +86 574 87089989.
E-mail address: nkxfliu@126.com
http://dx.doi.org/10.1016/j.poly.2014.01.034
0277-5387/Ó 2014 Elsevier Ltd. All rights reserved.

X.-F. Liu / Polyhedron 72 (2014) 66–71
67
2.3. Synthesis of (
(2)
l
-HC„CCH2CH2CH2CH2C„CH-
l
)[Co2(CO)5(PPh3)]2
as the eluent. The main red band afforded 0.030 g (29%) of 5 as a
red solid. Anal. Calc. for C45H36Co4O10P2: C, 52.25; H, 3.51. Found:
C, 51.94; H, 3.27%. IR (KBr disk, cmꢁ1): mC
„ 2060 (vs), 2000 (vs),
O
To a solution of 1 (0.068 g, 0.1 mmol) and PPh3 (0.052 g,
0.2 mmol) in CH2Cl2 (5 mL) was added a solution of Me3NOꢀ2H2O
(0.022 g, 0.2 mmol) in MeCN (5 mL). The new mixture was stirred
for 1 h. The solvent was reduced in vacuo and the residue was sub-
jected to TLC separation using CH2Cl2/petroleum ether (v/v = 1:5)
as the eluent. The main red band afforded 0.068 g (59%) of 2 as a
red solid. Anal. Calc. for C54H40Co4O10P2: C, 56.57; H, 3.52. Found:
1954 (vs). 1H NMR (500 MHz, CDCl3, ppm): 7.35–7.27 (m, 20H,
PhH), 5.24 (s, 2H, 2C„CH), 2.91–2.77 (m, 4H, 2CH„CCH2), 2.19–
2.14 (m, 4H, 2PCH2), 2.04–1.99 (m, 2H, PCH2CH2CH2P), 1.90–1.85
(m, 4H, CH„CCH2CH2CH2CH2C„CH). 31P{1H} NMR (200 MHz,
CDCl3, 85% H3PO4, ppm): 45.40 (s). 13C{1H} NMR (125 MHz, CDCl3,
ppm): 206.14, 204.31, 202.04 (C„O), 137.11, 136.76, 135.45,
135.12, 131.53, 131.47, 131.45, 131.34, 131.26, 130.17, 131.01,
128.65, 128.58, 128.55 (PhC), 91.98 (C„CH), 71.46 (C„CH),
31.97, 31.87 (HC„CCH2CH2CH2CH2C„CH), 29.72, 29.17 (PCH2CH2
CH2P). ESI-MS: m/z 1034.9095 [M++H] (Calc. 1034.9190).
C, 56.88; H, 3.36%. IR (KBr disk, cmꢁ1): mC
„
2054 (vs), 2000
O
(vs), 1953 (vs). 1H NMR (500 MHz, CDCl3, ppm): 7.50–7.29 (m,
30H, PhH), 5.19 (s, 2H, 2C„CH), 1.84–1.76 (m, 4H, 2CH„CCH2),
1.21–1.08 (m, 4H, CH„CCH2CH2CH2CH2C„CH). 31P{1H} NMR
(200 MHz, CDCl3, 85% H3PO4, ppm): 54.68 (s). 13C{1H} NMR
(125 MHz, CDCl3, ppm): 206.24, 205.14, 202.30 (C„O), 134.88,
134.55, 132.98, 132.90, 130.25, 128.53, 128.46 (PhC), 94.53
(C„CH), 71.73 (C„CH), 32.10, 31.57, 29.71 (CH2). ESI-MS: m/z
1145.9421 [M+] (Calc. 1145.9425).
2.6. Synthesis of (l-HC„CCH2CH2CH2CH2C„CH-l)[Co2(CO)5]2(dppb)
(6)
To a solution of 1 (0.068 g, 0.1 mmol) and dppb (0.043 g,
0.1 mmol) in CH2Cl2 (5 mL) was added a solution of Me3NOꢀ2H2O
(0.022 g, 0.2 mmol) in MeCN (5 mL). The new mixture was stirred
for 1 h. The solvent was reduced in vacuo and the residue was sub-
jected to TLC separation using CH2Cl2/petroleum ether (v/v = 1:3)
as the eluent. The main red band afforded 0.038 g (36%) of 6 as a
red solid. Anal. Calc. for C46H38Co4O10P2: C, 52.70; H, 3.65. Found:
2.4. Synthesis of (
(3) and ( -HC„CCH2CH2CH2CH2C„CH-
[Co2(CO)6][Co2(CO)4(dppe)] (4)
l-HC„CCH2CH2CH2CH2C„CH-l)[Co2(CO)5]2(dppe)
l
l)
C, 52.54; H, 3.89%. IR (KBr disk, cmꢁ1): mC
„
2059 (vs), 2000
To a solution of 1 (0.068 g, 0.1 mmol) and dppe (0.040 g,
0.1 mmol) in CH2Cl2 (5 mL) was added a solution of Me3NOꢀ2H2O
(0.022 g, 0.2 mmol) in MeCN (5 mL). The new mixture was stirred
for 1 h. The solvent was reduced in vacuo and the residue was sub-
jected to TLC separation using CH2Cl2/petroleum ether (v/v = 1:3)
as the eluent. The first red band afforded 0.020 g (20%) of 3 as a
red solid, whilst the second red band afforded 0.016 g (16%) of 4
as a red solid. 3: Anal. Calc. for C44H34Co4O10P2: C, 51.79; H, 3.36.
O
(vs), 1954 (vs). 1H NMR (500 MHz, CDCl3, ppm): 7.65, 7.42 (2s,
20H, PhH), 4.71 (s, 2H, 2C„CH), 2.96–2.72 (m, 4H, 2CH„CCH2),
2.12–2.06 (m, 8H, PCH2CH2CH2CH2P), 1.87 (s, 4H, CH„CCH2CH2
CH2CH2C„CH). 31P{1H} NMR (200 MHz, CDCl3, 85% H3PO4, ppm):
46.60 (s). 13C{1H} NMR (125 MHz, CDCl3, ppm): 207.86, 204.20,
201.97 (C„O), 133.45, 133.36, 131.84, 131.56, 130.74, 129.72,
129.52, 128.62 (PhC), 91.59 (C„CH), 73.72 (C„CH), 33.50, 32.58
(HC„CCH2CH2CH2CH2C„CH), 30.94 (d, JP-C = 21.9 Hz, PCH2),
25.62 (d, JP-C = 12.1 Hz, PCH2CH2). ESI-MS: m/z 1047.9249 [M+]
(Calc. 1047.9268).
Found: C, 52.02; H, 3.59%. IR (KBr disk, cmꢁ1): mC
„ 2056 (vs),
O
1999 (vs), 1988 (vs), 1955 (vs). 1H NMR (500 MHz, CDCl3, ppm):
7.42–7.27 (m, 16H, o-PhH and m-PhH), 7.15–7.12 (m, 4H, p-PhH),
4.94 (s, 2H, 2C„CH), 2.91–2.79 (m, 4H, 2CH„CCH2), 2.24–2.19
(m, 2H, PCH2), 2.09–2.04 (m, 2H, PCH2), 1.87–1.71 (m, 4H,
CH„CCH2CH2CH2CH2CCH). 31P{1H} NMR (200 MHz, CDCl3, 85%
H3PO4, ppm): 49.46 (s). 13C{1H} NMR (125 MHz, CDCl3, ppm):
207.74, 204.67, 201.70 (C„O), 136.81, 136.48, 133.68, 133.38,
133.01, 132.97, 130.59, 130.14, 129.84, 128.77 (PhC), 92.63
(C„CH), 73.20 (C„CH), 33.01, 30.18 (HC„CCH2CH2CH2CH2
C„CH), 25.64 (t, JP-C = 9.6 Hz, PCH2). ESI-MS: m/z 1019.8929 [M+]
(Calc. 1019.8955). 4: Anal. Calc. for C44H34Co4O10P2: C, 51.79; H,
2.7. X-ray structure determination
Single crystals of 1–3 and 6 suitable for X-ray diffraction analy-
sis were grown by slow evaporation of CH2Cl2/hexane solutions at
4 °C. A single crystal of 1–3 or 6 was mounted on a Rigaku MM-007
CCD diffractometer. Data were collected at 113 or 293 K using a
graphite monochromator with Mo K
a radiation (k = 0.71073 Å) in
the -/ scanning mode. Data collection, reduction and absorption
x
3.36. Found: C, 51.58; H, 3.54%. IR (KBr disk, cmꢁ1): mC
„ 2056
O
corrections were performed by the CRYSTALCLEAR program [14]. The
structures were solved by direct methods using the SHELXS-97 pro-
gram and refined by full-matrix least-squares techniques using
SHELXL-97 [15] on F2. Hydrogen atoms were located using the
geometric method. Details of crystal data, data collections and
structure refinement are summarized in Table 1.
(vs), 1999 (vs), 1986 (vs), 1956 (vs). 1H NMR (500 MHz, CDCl3,
ppm): 7.49–7.39 (m, 12H, m-PhH and p-PhH), 7.31–7.24 (m, 8H,
o-PhH), 5.42 (s, 2H, 2C„CH), 3.06, 3.03, 2.86, 2.83 (AB q, JAB = 3.9
Hz, 4H, 2CH„CCH2), 2.02 (d, J = 8.5 Hz, 2H, PCH2), 1.88, 1.86 (2s,
6H, PCH2 and CH„CCH2CH2CH2CH2C„CH). 31P{1H} NMR
(200 MHz, CDCl3, 85% H3PO4, ppm): 48.41 (s). 13C{1H} NMR
(125 MHz, CDCl3, ppm): 205.60, 204.17, 201.87 (C„O), 135.81,
135.49, 134.06, 133.76, 133.00, 132.96, 132.11, 132.08, 131.39,
131.35, 130.68, 130.35, 128.88, 128.84, 128.81 (PhC), 91.15
(C„CH), 70.56 (C„CH), 33.46, 28.93 (HC„CCH2CH2CH2CH2CCH),
25.41 (d, JP-C = 13.5 Hz, PCH2). ESI-MS: m/z 1019.8949 [M+] (calc.
1019.8955).
3. Results and discussion
3.1. Synthesis and characterization
As shown in Scheme 1, the reactions of 1 with PPh3, dppp or
dppb in the presence of Me3NOꢀ2H2O afforded 2, 5 and 6 in
29–59% yields, respectively, whereas the reaction of 1 with dppe
in the presence of Me3NOꢀ2H2O resulted in the formation of 3
and 4 in 20 and 16% yields, respectively. While complex 2 contains
the monophosphine PPh3, complexes 3–6 contain the bridging
diphosphines dppe, dppp or dppb.
The new complexes 2–6 are air-stable red solids, which have
been characterized by elemental analysis and various spectro-
scopic techniques. The IR spectra of 2–6 displayed three to four
2.5. Synthesis of (l-HC„CCH2CH2CH2CH2C„CH-l)[Co2(CO)5]2(dppp)
(5)
To a solution of 1 (0.068 g, 0.1 mmol) and dppp (0.041 g,
0.1 mmol) in CH2Cl2 (5 mL) was added a solution of Me3NOꢀ2H2O
(0.022 g, 0.2 mmol) in MeCN (5 mL). The new mixture was stirred
for 1 h. The solvent was reduced in vacuo and the residue was sub-
jected to TLC separation using CH2Cl2/petroleum ether (v/v = 1:3)

68
X.-F. Liu / Polyhedron 72 (2014) 66–71
Table 1
Crystal data and structure refinements details for 1–3 and 6.
Complex
1
2
3ꢀ0.25CH2Cl2
6
Empirical formula
Formula weight
Temperature (K)
Wavelength (Å)
Crystal system
Space group
a (Å)
C
20H10Co4O12
C27H20Co2O5P
573.26
113(2)
C44.25H34.50Cl0.50Co4O10P2
1041.60
293(2)
C92H76Co8O20P4
2096.86
293(2)
0.71073
monoclinic
P2(1)/n
25.289(5)
17.020(3)
28.526(6)
90
115.52(3)
90
11079(4)
4
1.258
678.00
113(2)
0.71073
triclinic
P1
6.857(7)
0.71073
triclinic
0.71073
triclinic
ꢀ
ꢀ
ꢀ
P1
P1
8.199(7)
9.019(8)
9.829(2)
b (Å)
c (Å)
7.655(7)
10.983(2)
23.493(5)
87.50(3)
78.03(3)
74.34(3)
2388.9(8)
2
1.448
12.584(11)
98.796(8)
101.490(19)
103.429(16)
615.7(10)
1
17.782(14)
102.896(13)
91.200(13)
100.303(10)
1258.5(17)
2
a
(°)
b (°)
c
(°)
V (Å3)
Z
Dcalc (g cmꢁ3
)
1.829
2.707
1.513
1.417
l
(mmꢁ1
)
1.512
1.281
F(000)
334
582
1053
4260
Crystal size (mm3)
hmin, hmax (°)
0.20 ꢂ 0.18 ꢂ 0.12
1.69, 27.96
6377/2895
0.0408
0.20 ꢂ 0.18 ꢂ 0.12
2.35, 25.02
10607/4433
0.0638
0.20 ꢂ 0.18 ꢂ 0.12
1.77, 25.02
19438/8350
0.0416
0.28 ꢂ 0.24 ꢂ 0.20
1.42, 25.02
88916/19527
0.1527
Reflections collected/unique
Rint
hkl range
ꢁ8 6 h 6 8
ꢁ10 6 k 6 10
ꢁ16 6 l 6 16
98.2
2895/0/163
1.049
ꢁ9 6 h 6 9
ꢁ10 6 k 6 10
ꢁ18 6 l 6 21
99.8
4433/0/317
1.023
ꢁ11 6 h 6 11
ꢁ13 6 k 6 13
ꢁ27 6 l 6 26
99.2
8350/31/569
1.075
ꢁ30 6 h 6 29
ꢁ20 6 k 6 20
ꢁ33 6 l 6 30
99.7
19527/2568/1106
1.219
Completeness to hmax (%)
Data/restraints/parameters
Goodness of fit on F2
R1/wR2 (I > 2
r
(I))
0.0289/0.0725
0.0305/0.0736
0.449/ꢁ0.989
0.0820/0.2263
0.1096/0.2492
1.431/ꢁ0.994
0.0551/0.1849
0.0648/0.1957
1.409/ꢁ0.425
0.1641/0.4022
0.2881/0.4665
1.196/ꢁ0.582
R1/wR2 (all data)
Largest difference in peak and hole (e Åꢁ3
)
(OC)3Co
Co(CO)2(PPh3)
PPh3, Me3NO
(OC)3Co
Co(CO)2(PPh3)
2
CO
Ph2
P
Ph2
P
OC
OC
Co
Co
CO
CO
OC
Co
Co
(CO)
(CO)
OC
OC
3
dppe, Me3NO
(OC)3Co
Co(CO)3
(OC)3Co
Co(CO)3
(OC)3Co
Co(CO)3
PPh2
(OC)3Co
Co(CO)3
P
Ph2
4
1
CO
Ph2
P
OC
OC
Ph2
P
dppp, Me3NO
dppb, Me3NO
OC
OC
OC
Co
Co
CO
CO
Co
Co
(CO)
(CO)
5
CO
Ph2
Ph2
P
P
OC
OC
OC
Co
Co
CO
CO
OC
Co
Co
(CO)
(CO)
OC
6
Scheme 1. Preparation of complexes 2–6.

X.-F. Liu / Polyhedron 72 (2014) 66–71
69
Fig. 1. ORTEP view of 1 with 30% probability level ellipsoids.
Fig. 2. ORTEP view of 2 with 30% probability level ellipsoids.
absorption bands in the region 2060–1953 cmꢁ1 for their terminal
carbonyls and the mC values moved towards lower frequencies
with respect to 1 (2093, 2049, 2028, 2005 and 1995 cmꢁ1) but
were very close to the bands for ( -FcC„CH)Co2(CO)5(PPh3)
and 2 consist of two pseudo-tetrahedral [C2Co2] clusters with
twelve terminal carbonyls or ten terminal carbonyls and two
PPh3 ligands, which are joined together through a zigzag chain,
C8C9C10C10AC9AC8A or C7C8C9C9AC8AC7A. The molecules of 1
and 2 are centrosymmetric, with the midpoint of C10–C10A
or C9–C9A as an inversion center. The Co–Co bond lengths
[2.482(2) Å for 1 and 2.4602(19) Å for 2] and the triple bond
lengths [C7–C8 = 1.345(2) Å for 1 and C6–C7 = 1.341(9) Å for 2] are
comparable to the previously reported complexes C20H8[Co2(CO)6]2
„
O
l
(Fc = ferrocene) (2055, 1999 and 1963 cmꢁ1) [16]. The 1H NMR
spectra of 2–6 showed a singlet at 5.42–4.71 ppm for the acety-
lenic protons. The 31P{1H} NMR spectra of 2–6 exhibited a singlet
at 54.68–45.40 ppm for the phosphorus atoms of PPh3, dppe, dppp
or dppb coordinated to the cobalt atoms. The 13C{1H} NMR spectra
of 2–6 demonstrated three singlets at about 200 ppm for the
terminal carbonyls and two singlets at about 90 and 70 ppm for
the acetylenic carbons.
[17] and (l-FcC„CH)Co2(CO)4(dppm) (dppm = Ph2PCH2PPh2) [18].
The phosphorus atom of PPh3 in 2 resides in an apical position
of the square-pyramidal coordination sphere of the cobalt atom,
consistent with the crystal structure of (
[16].
l-FcC„CH)Co2(CO)5(PPh3)
3.2. X-ray crystal structures
As shown in Figs. 3 and 4, complexes 3 and 6 consist of two
pseudo-tetrahedral [C2Co2] clusters with ten terminal carbonyls
and dppe or dppb. The macrocycles of 3 and 6 have 12 and 14
The molecular structures of 1–3 and 6 were determined by sin-
gle crystal X-ray diffraction analysis. While ORTEP views of 1–3
and 6 are shown in Figs. 1–4, selected bond lengths and angles
are presented in Table 2. As shown in Figs. 1 and 2, complexes 1
atoms, respectively, which are joined together by
a zigzag
chain, C38C39C40C41C42C43 or C40C41C42C43C44C45, and a

70
X.-F. Liu / Polyhedron 72 (2014) 66–71
Table 2
Selected bond lengths (Å) and angles (°) for 1–3 and 6.
1
Co(1)–C(7)
Co(1)–C(8)
Co(1)–Co(2)
Co(2)–C(7)
C(7)–Co(1)–C(8)
C(7)–Co(1)–Co(2)
C(8)–Co(1)-Co(2)
C(7)–Co(2)–C(8)
C(7)–Co(2)–Co(1)
1.9571(2)
1.972(2)
2.482(2)
1.956(2)
40.04(7)
50.63(7)
51.09(5)
40.02(6)
50.66(5)
Co(2)–C(8)
C(7)–C(8)
C(8)–C(9)
C(9)–C(10)
C(8)–Co(2)–Co(1)
C(8)–C(7)–Co(2)
C(8)–C(7)–Co(1)
Co(2)–C(7)–Co(1)
Co(1)–C(8)–Co(2)
1.975(2)
1.345(2)
1.489(2)
1.524(3)
51.00(7)
70.73(1)
70.60(1)
78.71(8)
77.91(8)
2
Co(1)–C(7)
Co(1)–C(6)
Co(1)–Co(2)
Co(2)–C(6)
C(7)–Co(1)–C(6)
C(7)–Co(1)–Co(2)
C(6)–Co(1)–Co(2)
C(6)–Co(2)–C(7)
C(6)–Co(2)–P(1)
1.982(8)
2.000(9)
2.4602(2)
1.950(7)
39.3(3)
50.9(2)
50.6(2)
40.2(3)
104.1(3)
Co(2)–C(7)
Co(2)–P(1)
C(6)–C(7)
C(7)–C(8)
C(7)–Co(2)–P(1)
C(6)–Co(2)–Co(1)
C(7)–Co(2)–Co(1)
P(1)–Co(2)–Co(1)
C(7)–C(6)–Co(1)
1.956(8)
2.212(2)
1.341(9)
1.511(1)
102.4(2)
52.4(3)
51.8(2)
153.13(7)
69.6(5)
3
Co(1)–C(44)
Co(1)–C(43)
Co(1)–Co(2)
Co(2)–C(44)
C(44)–Co(1)–C(43)
C(44)–Co(1)–Co(2)
C(43)–Co(1)–Co(2)
C(44)–Co(2)–C(43)
C(44)–Co(2)–P(1)
1.984(6)
1.992(5)
2.4890(1)
1.934(5)
38.8(2)
49.67(2)
50.19(2)
39.7(2)
Co(2)–C(43)
Co(3)–Co(4)
C(43)–C(44)
C(37)–C(38)
C(43)–Co(2)–P(1)
C(44)–Co(2)–Co(1)
C(43)–Co(2)–Co(1)
P(1)–Co(2)–Co(1)
C(37)–C(38)–C(39)
1.953(5)
2.4882(1)
1.321(8)
1.328(8)
99.02(2)
51.47(2)
51.59(1)
150.07(5)
141.7(5)
Fig. 3. ORTEP view of 3 with 30% probability level ellipsoids.
diphosphine ligand, dppe or dppb. The Co–Co bond lengths
[2.4890(13) and 2.4882(13) Å for 3, and 2.487(3) and 2.441(3) Å
for 6] are close to that of 1, whereas the triple bond lengths
[C37–C38 = 1.328(8) Å and C43–C44 = 1.321 (8) Å for 3, and C39–
C40 = 1.27(2) Å and C45–C46 = 1.26(2) Å for 6] are somewhat
shorter than that of 1. It should be noted that the two phosphorus
atoms of dppe or dppb both reside in an apical position of the
square-pyramidal coordination sphere of the cobalt atoms, in good
agreement with 2 and analogous dicobalt complexes [19]. In addi-
tion, the structure of 6 is of lower quality than 3 and there are 2568
restraints in the crystal refinement because of so many disordered
103.64(2)
6
Co(1)–C(40)
Co(1)–C(39)
Co(1)–Co(2)
Co(2)–C(40)
C(40)–Co(1)–C(39)
C(40)–Co(1)–Co(2)
C(39)–Co(1)–Co(2)
C(40)–Co(2)–C(39)
P(1)–Co(2)–Co(1)
1.983(1)
2.010(2)
2.487(3)
1.939(2)
37.2(6)
49.9(5)
51.1(5)
37.9(6)
147.06(1)
Co(2)–C(39)
C(45)–C(46)
Co(3)–Co(4)
C(39)–C(40)
C(46)–Co(3)–C(45)
P(2)–Co(3)–Co(4)
C(39)–C(40)–C(41)
C(46)–C(45)–C(44)
C(23)–C(24)–C(25)
1.987(2)
1.26(2)
2.441(3)
1.27(2)
37.8(6)
151.85(2)
130.3(2)
144.0(2)
111.9(1)
Fig. 4. ORTEP view of 6 with 30% probability level ellipsoids.

X.-F. Liu / Polyhedron 72 (2014) 66–71
71
solvent molecules in the crystal structure. The room temperature
analysis and poor crystal quality may lead to such results.
58010), the Zhejiang Province Science and Technology Innovation
Program (2013R422014) and Ningbo Science and Technology
Innovation Team (2011B82002).
3.3. Discussion
Appendix A. Supplementary material
The present work reports a novel series of diacetylenic tetraco-
balt carbonyl complexes with the monophosphine ligand PPh3 or
bridging diphosphine ligands, dppe, dppp or dppb. The reactions
of the starting material 1 with dppe, dppp or dppb resulted in
the formation of two coordination modes: macrocycle and intra-
molecular bridging. The macrocyclic complex 3 and intramolecular
bridging complex 4 were obtained from the reaction of dppe at the
same time and the structure of 3 was determined by X-ray crystal-
lography, whereas the structure of 4 was deduced from 1H, 31P{1H}
and 13C{1H} NMR and ESI-MS spectroscopy. It is very interesting
that when dppe was replaced by dppp or dppb, the same type of
reactions yielded products with only one coordination mode: the
macrocyclic complexes 5 and 6. X-ray analysis also revealed the
structure of 6. Unfortunately, all attempt to grow suitable single
crystals of 4 and 5 failed. A detailed mechanism for the reactions
is still uncertain and will need deeper study.
CCDC 971422–971425 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from http://www.ccdc.cam.ac.uk/conts/retrieving.html, or
from the Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336 033; or e-mail:
deposit@ccdc.cam.ac.uk.
References
[1] H. Greenfield, H.W. Sternberg, R.A. Friedel, J.H. Wotiz, R. Markby, I. Wender, J.
Am. Chem. Soc. 78 (1956) 120.
[2] N.E. Schore, Chem. Rev. 88 (1988) 1081.
[3] S.D. Najdi, M.M. Olmstead, N.E. Schore, J. Organomet. Chem. 431 (1992) 335.
[4] Y. Rubin, C.B. Knobler, F. Diederich, J. Am. Chem. Soc. 112 (1990) 4966.
[5] L.S. Chia, W.R. Cullen, M. Franklin, A.R. Manning, Inorg. Chem. 14 (1975) 2521.
[6] E. Sappa, G. Predieri, L. Marko, Inorg. Chim. Acta 228 (1995) 147.
[7] K. Yang, S.G. Bott, M.G. Richmond, Organometallics 13 (1994) 3788.
[8] S. Clément, L. Guyard, A. Khatyr, M. Knorr, Y. Rousselin, M.M. Kubicki, Y.
Mugnier, S. Richeter, P. Gerbier, C. Strohmann, J. Organomet. Chem. 699 (2012)
56.
4. Summary
[9] M.J. Macazaga, M.L. Marcos, C. Moreno, F. Benito-Lopez, J. Gomez-González, J.
González-Velasco, R.M. Medina, J. Organomet. Chem. 691 (2006) 138.
[10] X.-F. Liu, Z.-Q. Jiang, Z.-J. Jia, Polyhedron 33 (2012) 166.
[11] X.-F. Liu, H.-Q. Gao, Polyhedron 65 (2013) 1.
[12] X.-F. Liu, X.-W. Xiao, J. Organomet. Chem. 696 (2011) 2767.
[13] X.-F. Liu, J. Organomet. Chem. 750 (2014) 117.
[14] CRYSTALCLEAR 1.3.6. Rigaku and Rigaku/MSC. The Woodlands, TX, 2005.
[15] G.M. Sheldrick, SHELXS97 and SHELXL97, A Program for Crystal Structure Solution,
University of Göttingen, Germany, 1997.
In summary, the reactions of complex 1 with PPh3, dppe, dppp
or dppb afforded diacetylenic tetracobalt carbonyl complexes 2–6
in moderate yields. The new complexes 2–6 were characterized
by elemental analysis, spectroscopy and, in some cases, by X-ray
crystallography. These macrocyclic complexes may have potential
applications in supramolecular chemistry.
[16] J.-H. Ye, Q.-L. Suo, Y.-B. Wang, L.-M. Han, X.-B. Leng, J. Inorg. Chem. 20 (2004)
559.
[17] R.D. Adams, U.H.F. Bunz, W. Fu, L. Nguyen, J. Organomet. Chem. 578 (1999) 91.
[18] V. Derdau, S. Laschat, Organometallics 18 (1999) 3859.
[19] R.H. Cragg, J.C. Jeffery, M.J. Went, J. Chem. Soc., Chem. Commun. (1990) 993.
Acknowledgements
This work was supported by the National Training Programs of
Innovation and Entrepreneurship for Undergraduates (2013110