Tri- and tetracoordinate copper(I) complexes bearing bidentate soft/hard SN and SeN ligands based on 2-aminopyridine

Article abstract of DOI:10.1039/c1dt10377f

The coordination properties of the EN ligands N-(2-pyridinyl)amino- diphenylphosphine sulfide, N-(2-pyridinyl)amino-diisopropylphosphine sulfide, N-(2-pyridinyl)amino-diphenylphosphine selenide, N-(2-pyridinyl)amino- diisopropylphosphine selenide towards copper(i) precursors CuX (X = Br, I), [Cu(IPr)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), and [Cu(CH₃CN)₄]PF₆ were studied. Treatment of CuX with EN ligands resulted in the formation of tricoordinate complexes of the type [Cu(κ²(E,N)-EN)X]. The reaction of [Cu(IPr)Cl] with EN ligands, followed by halide abstraction with AgSbF₆, afforded cationic tricoordinate complexes [Cu(κ²(S,N)-EN)(IPr)] ⁺, while the reaction of [Cu(CH₃CN)₄] ⁺ with two equivalents of EN ligands yielded tetrahedral complexes [Cu(κ²(E,N)-EN)₂]⁺. Halide removal from [Cu(κ²(S,N)-SN)I] with silver salts in the presence of L = CH₃CN and CNtBu afforded dinuclear complexes of the type [Cu(κ²(S,N),μ(S)-SN)(L)]₂²⁺ containing bridging SN ligands. With the terminal alkynes HCCC₆H₄Me and HCCC₆H₄OMe, complexes of the formula [Cu(κ²(S,N)-SN-iPr)(η²-HCCC₆H ₄Me)]⁺ and [Cu(κ²(S,N)-SN-iPr) (η²-HCCC₆H₄OMe)]⁺ were obtained. The mononuclear nature of these compounds was supported by DFT calculations. Most complexes were also characterized by X-ray crystallography.

Full text of DOI:10.1039/c1dt10377f

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PAPER
Tri- and tetracoordinate copper(I) complexes bearing bidentate soft/hard SN
and SeN ligands based on 2-aminopyridine†
a
b
c
a
¨
¨
Ozgu¨r Oztopcu, Kurt Mereiter, Michael Puchberger and Karl A. Kirchner*
Received 4th March 2011, Accepted 20th April 2011
DOI: 10.1039/c1dt10377f
The coordination properties of the EN ligands N-(2-pyridinyl)amino-diphenylphosphine sulfide,
N-(2-pyridinyl)amino-diisopropylphosphine sulfide, N-(2-pyridinyl)amino-diphenylphosphine selenide,
N-(2-pyridinyl)amino-diisopropylphosphine selenide towards copper(I) precursors CuX (X = Br, I),
[Cu(IPr)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), and [Cu(CH3CN)4]PF6 were
studied. Treatment of CuX with EN ligands resulted in the formation of tricoordinate complexes of the
2
type [Cu(k (E,N)-EN)X]. The reaction of [Cu(IPr)Cl] with EN ligands, followed by halide abstraction
2
with AgSbF6, afforded cationic tricoordinate complexes [Cu(k (S,N)-EN)(IPr)]+, while the reaction of
2
[Cu(CH3CN)4]+ with two equivalents of EN ligands yielded tetrahedral complexes [Cu(k (E,N)-EN)2]+.
2
Halide removal from [Cu(k (S,N)-SN)I] with silver salts in the presence of L = CH3CN and CNtBu
2
2+
afforded dinuclear complexes of the type [Cu(k (S,N),m(S)-SN)(L)]2 containing bridging SN ligands.
With the terminal alkynes HC CC6H4Me and HC CC6H4OMe, complexes of the formula
2
2
2
2
[Cu(k (S,N)-SN-iPr)(h -HC CC6H4Me)]+ and [Cu(k (S,N)-SN-iPr)(h -HC CC6H4OMe)]+ were
obtained. The mononuclear nature of these compounds was supported by DFT calculations. Most
complexes were also characterized by X-ray crystallography.
phosphorus-nitrogen bond forming reactions, compared to those
Introduction
in which phosphorus-carbon bonds are formed, it is not surprising
that many examples of transition metal complexes featuring this
type of PN ligands have emerged over the last few decades.5–14
The most prominent member of this ligand family, with a few
exceptions,15 is N-diphenylphosphino-2-aminopyridine (PN-Ph).
Another very useful and interesting aspect of PN ligands is the fact
that they can also be readily functionalized at the phosphorus site
by oxidation with H2O2, sulfur, and gray selenium, respectively,
to give chalcogen O, S, and Se derivatives (EN ligands), as
shown in Scheme 1. Despite the fact that the synthesis of these
heterodifunctional EN ligands has been known for some time,11
it is surprising that transition metal complexes containing these
ligands are relatively scarce.7,10,16,17
As part of our ongoing interest in transition metal complexes
containing heterodifunctional ligands,2,3 we herein report on the
synthesis, structure, and reactivity of tri- and tetracoordinate Cu(I)
complexes featuring soft/hard SN and SeN ligands with R = Ph
and iPr, as shown in Scheme 1. These ligands are expected to
form stable and perhaps unusual complexes due the favorable soft
acid–soft base interaction with this closed-shell d10 metal ion.18
Heterodifunctional ligands are intensively studied and applied in
coordination and organometallic chemistry owing to the often
unique properties of their metal complexes and their ability
to generate hemilabile systems which often display enhanced
reactivity.1 In particular, soft/hard, e.g., P/N and P/O assemblies,
are able to coordinate reversibly to a metal center providing or
protecting temporarily a vacant coordination site, a feature very
desirable for catalysts.
In this context, we have become interested in heterodifunctional
PN ligands based on 2-aminopyridine in which the donor atoms
are separated by an amino group.2,3 These types of ligands are
easily constructed by reacting 2-aminopyridine with R2PCl in the
presence of a base (Scheme 1). R2PCl may contain both bulky
and/or electron-rich dialkyl phosphines as well as P–O and P–N
bond containing achiral and chiral phosphite units derived from
diols, aminoalcohols, and diamines.4 Due the comparative ease of
aInstitute of Applied Synthetic Chemistry, Vienna University of Tech-
nology, Getreidemarkt 9, A-1060, Vienna, Austria. E-mail: kkirch@
mail.tuwien.ac.at; Fax: +43-1-58801-16399
bInstitute of Chemical Technologies and Analytics, Vienna University of
Technology, Getreidemarkt 9, A-1060, Vienna, Austria
Results and discussion
cInstitute of Materials Chemistry, Vienna University of Technology, Getrei-
demarkt 9, A-1060, Vienna, Austria
The coordination properties of the EN ligands 1 and 2 to-
wards the copper(I) precursors CuX (X = Br, I), [Cu(IPr)Cl]
† Electronic supplementary information (ESI) available: 1H–15N HSQC
spectra of 2b and 5b. CCDC reference numbers 810363–810377. For ESI
and crystallographic data in CIF or other electronic format see DOI:
10.1039/c1dt10377f
(IPr
= 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), and
[Cu(CH3CN)4]PF6 were investigated. Treatment of CuX with
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Scheme 1
1 equiv. of 1 and 2 in THF at room temperature resulted in the
2
formation of tricoordinate complexes of the type [Cu(k (E,N)-
EN)X] (3–6) in 68 to 85% isolated yields (Scheme 2). The
reaction of [Cu(IPr)Cl] with one equiv. of 1 in THF, followed by
halide abstraction with AgSbF6, afforded cationic tricoordinate
2
2
complexes [Cu(k (S,N)-SN-Ph)(IPr)]SbF6 (7a) and [Cu(k (S,N)-
SN-iPr)(IPr)]SbF6 (7b) in good isolated yields (Scheme 3). When
[Cu(CH3CN)4]+ was treated with one equiv. of 1 and 2, respectively,
2
tetrahedral complexes of the type [Cu(k (E,N)-EN)2]+ (8, 9)
were obtained in low yields. There was no evidence for the
2
formation of the expected bis-acetonitrile complex [Cu(k (E,N)-
EN)(CH3CN)2]+. In addition, substantial amounts of the starting
material were recovered. When the same reaction was performed
with two equiv. of EN ligands, complexes 8 and 9 were obtained
in high isolated yields (Scheme 4).
Scheme 4
were determined by H–15N HMBC and H–15N HSQC NMR
experiments (performed with 15N natural abundance, referenced to
NH4Cl). In the 1H–15N HMBC spectra of both 2b and 5b, depicted
in Fig. 1, cross peaks were observed between the pyridine nitrogen
atom and the pyridine protons H3, H5, and H6 that provided the
15N chemical shifts at 252 and 222 ppm, respectively. In the 1H–15N
HSQC spectra (see ESI†), cross peaks between the amine nitrogen
and the NH protons were observed giving rise to 15N chemical
shifts at 66 and 58 ppm, respectively. Accordingly, coordination of
SN-iPr to copper(I) leads to an up-field shift of the 15N resonances.
1
1
In the 31P{ H} NMR spectra, all compounds exhibit singlets for
1
2
the k (E,N)-coordinated EN ligands which are all slightly high-
field shifted relative to the free uncoordinated ligands. Moreover,
the phosphorus signals of the SeN ligands exhibit a singlet with a
pair of Se satellites with 31P–77Se coupling constants in the range
of 787 to 673 Hz.
Scheme 2
The molecular structures of the ligands 1a, 1b, 2a, 2b and of the
complexes 3a, 3b, 5b, 6b, 7a, 7b, and 8b were determined by X-ray
crystallography. Structural diagrams for 1a, 1b, 3a, 5b, 7a, and 8b
are depicted in Fig. 2–7 with selected bond distances and angles
reported in the captions. Structural views of 2a, 2b, 3b, 6b, and 7b
are given in the ESI.†
The free EN ligands 1a, 1b, 2a, and 2b exhibit in solid state
bond lengths which do not differ significantly from those of their
Cu-complexes (see below), except that P–S bonds are shorter
˚
than those in the Cu-complexes by about 0.03 A. However, the
conformation of the free ligands differs from that of the Cu-
complexes (see below) because the S and Se atoms are turned
away from the pyridine N-atoms, as shown for instance in
Fig. 2, whereas in all Cu-complexes the EN ligands are chelating
and S and Se atoms are turned to the pyridine N-atoms. It
is a characteristic feature of all free ligands that their N–H
groups form intermolecular hydrogen bonds to either the pyridine
N-atoms or the E-atoms (S, Se) as acceptors and that they build
up hydrogen bonded dimers. Whereas the phenyl-bearing ligands
Scheme 3
All the above complexes are thermally robust, white to pale
yellow solids that are air stable both in the solid state and
in solution for several days. Their identity was unequivocally
established by H, 13C{ H}, and 31P{ H} NMR, and elemental
1
1
1
analysis. In the case of the ligand 2b and complex 5b, the 15N shifts
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Fig. 3 ORTEP diagram of 1b showing the two independent molecules
of the structure with 50% displacement ellipsoids. Se-analogue 2b
is not isostructural. Carbon-bonded
H atoms omitted for clar-
ity. Selected distances and angles (A, ◦): P1–S1 1.9627(3), P2–S2
1.9596(3), P1–N2 1.6826(8), P2–N4 1.6830(8), N2–P1–S1 107.18(3),
N4–P2–S2 108.60(3), N1–C1–N2–P1 -8.9(1), N3–C12–N4–P2 -5.7(1),
C1–N2–P1–S1 -179.8(1), C12–N4–P2–S2 179.4(1), N2 ◊ ◊ ◊ S2 3.375(1),
N4 ◊ ◊ ◊ S1 3.470(1).
˚
Fig. 1 300 MHz 1H–15N HMBC spectra of SN-iPr (2b) and [Cu(SN-iPr)I]
(5b) in acetone-d6 at 25 ◦C.
Fig. 4 Molecular structure of 3a showing 50% displacement ellip-
soids. H atoms omitted for clarity. Selected distances and angles
(A, ◦): Cu1–N1 2.0597(12), Cu1–S1 2.2092(4), Cu1–Br1 2.3410(3),
˚
P1–S1 1.9791(5), P1–N2 1.6746(12), N2–C1 1.391(2), N1–Cu1–S1
113.51(3), N1–Cu1–Br1 111.67(3), S1–Cu1–Br1 133.73(1), P1–S1–Cu1
89.10(2), N2–P1–S1 117.18(4), C1–N2–P1 127.7(1), N1–C1–N2 118.6(1),
Cu1–N1–C1 122.6(1).
Fig. 2 ORTEP diagram of 1a showing the two independent molecules
of the structure with 50% displacement ellipsoids. The Se-analogue 2a
is isostructural. Carbon-bonded H atoms omitted for clarity. Selected
distances and angles (A, ◦): P1–S1 1.9470(4), P2–S2 1.9497(4), P1–N2
˚
Br1 is strongly distorted with bond lengths of Cu1–N1 2.0597(12),
1.6689(9), P2–N4 1.6706(9), N2–P1–S1 117.02(4), N4–P2–S2 115.89(3),
N1–C1–N2–P1 179.8(1), N3–C18–N4–P2 -151.5(1), C1–N2–P1–S1
-61.2(1), C18–N4–P2–S2 45.3(1), N2 ◊ ◊ ◊ N3 2.935(1), N4 ◊ ◊ ◊ N1 2.926(1).
˚
Cu1–S1 2.2092(4), Cu1–Br1 2.3410(3) A and bond angles between
◦
˚
111.67(3) and 133.73(1) . Copper deviates by 0.131 A from the
N1–S1–Br1 plane being displaced to the pyridine plane. The six-
membered chelate ring formed by the EN ligand has a ring bond
angle sum of 688.7◦ – the planar hexagon has 720◦ – and is
therefore distinctly puckered. Most responsible for this puckering
is the P–S–Cu bond angle, which is near 90◦ in all these Cu
complexes, for electronic reasons originating from S and Se. Using
the pyridine ring as the reference plane, the following deviations
from this plane are observed in compound 3a: N2 -0.03, P1 -0.34,
1a and 2a are isostructural and form N–H ◊ ◊ ◊ N bonded dimers,
the isopropyl-bearing ligands 1b and 2b are not isostructural and
form N–H ◊ ◊ ◊ S (1b; Fig. 3) or N–H ◊ ◊ ◊ Se bonded dimers (2b; see
ESI†).
Complexes 3a through 7b contain Cu in triangular and
approximately planar coordination geometry. As representative
2
example [Cu(k (S,N)-SN-Ph)Br] (3a) is shown in Fig. 4. The
˚
coordination triangle formed by the three ligands N1, S1 and
S1 0.97, Cu1 0.78, and Br1 1.59 A. A further consequence of
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Fig. 5 Molecular structure of 5b showing 50% displacement ellipsoids
(isostructural with 3b and 6b). H atoms omitted for clarity. Selected
◦
˚
distances and angles (A, ): Cu1–N1 2.0209(13), Cu1–S1 2.2174(5), Cu1–I1
2.4961(3), P1–S1 1.9900(5), P1–N2 1.6822(13), N1–Cu1–S1 116.00(4),
N1–Cu1–I1 114.41(4), S1–Cu1–I1 128.95(1), P1–S1–Cu1 92.73(2).
Fig. 7 Molecular structure of 8b showing 50% displacement ellipsoids.
-
PF6 anion and H atoms omitted for clarity. Selected distances and
angles (A, ◦): Cu1–N1 2.140(2), Cu1–N3 2.163(2), Cu1–S1 2.2602(8),
˚
Cu1–S2 2.2706(7), P1–S1 1.9860(7), P1–N2 1.676(2), P2–S2 1.9863(7),
P2–N4 1.678(2), N1–Cu1–N3 89.84(9), S1–Cu1–S2 128.22(4), N1–Cu1–S1
107.21(5), N3–Cu1–S2 106.29(5), N1–Cu1–S2 109.90(5), N3–Cu1–S1
108.63(5).
Complexes 7a and 7b, which contain a Cu–C bonded neutral
N-heterocyclic ligand (NHC) and an uncoordinated SbF6 anion
instead of a Cu-bonded halide anion maintain the triangular
coordination of Cu and the chelate ring puckering of the previous
˚
complexes. They show very short Cu–C bonds of ca. 1.92 A and
compensate this by having slightly longer Cu–N and Cu–S bonds,
along with some changes in the bond angles around Cu (Table
3). For example, the cationic complex 7a is shown in Fig. 6,
which reveals that the NHC ligand is oriented approximately
perpendicular to the Cu coordination triangle, a feature that also
holds true for 7b.
In complex 8b (Fig. 6) the copper atom adopts a distorted
tetrahedral coordination by two N and two S atoms from two
chelating SN-ligands. Here the Cu–N bonds are longer by about
˚
˚
0.10 A and the Cu–S bonds by about 0.06 A than in the previous
triangular Cu-complexes. Crystallographically the Cu-complex of
8b is C1-symmetric, but geometrically it is close to a C2 symmetry.
This C2-pseudosymmetry is also valid for the monoclinic crystal
Fig. 6 Molecular structure of 7a showing 50% displacement ellip-
-
soids. SbF6 anion, (CH3)2CO solvent molecule, and H atoms omitted
for clarity. Selected distances and angles (A, ◦): Cu1–C18 1.913(2),
˚
Cu1–N1 2.048(2), Cu1–S1 2.2674(8), P1–S1 1.9732(9), P1–N2 1.668(2),
C18–Cu1–N1 129.15(9), C18–Cu1–S1 121.60(8), N1–Cu1–S1 108.84(6),
P1–S1–Cu1 92.60(3).
¯
lattice of the compound in the lattice direction [101] perpendicular
to which the complex cations and the SbF6 counter anions are
-
linked into N–H ◊ ◊ ◊ F hydrogen bonded chains.
Complexes [Cu(k (S,N)-SN)I] (5a, 5b) were reacted with silver
2
the chelate ring puckering is that one of the two P–C bonds is
approximately parallel to the pyridine ring, whereas the second is
steeply inclined to it. The N2–H group of the complex forms an
intermolecular hydrogen bond to Br1 of a neighboring molecule,
salts in the presence of ligands such as CH3CN, CNtBu, PPh3,
terminal alkynes, olefins, and CO. Abstraction of the metal
bound halide from complexes 5a and 5b with AgSbF6 (1 equiv.)
in neat CH3CN led to the formation of the cationic com-
˚
N2 ◊ ◊ ◊ Br1 = 3.475(1) A, linking the complexes into infinite straight
2
2
chains.
plexes [Cu(k (S,N)-SN-Ph)(NCCH3)2]+ (10a) and [Cu(k (S,N)-
SN-iPr)(NCCH3)2]+ (10b), respectively (Scheme 5). It has to
be noted that these complexes were not accessible by treat-
ing [Cu(CH3CN)4]+ with stoichiometric amounts of the corre-
sponding SN ligands. They are stable in the solid state and
in acetonitrile solution. In other solvents, e.g., acetone or ni-
tromethane, both complexes dimerize slowly to afford com-
The isopropyl-substituted complexes 3b (S, Br), 5b (S, I), and
6b (Se, I) form an isostructural series with monoclinic symmetry
and space group P21/c, of which 5b is shown as a representative
example in Fig. 5. These complexes follow essentially the geometric
characteristics outlined already for complex 3a. A comparison of
important geometric data of these complexes is given in Table 1.
In their crystal lattice the complexes are linked by intermolecular
N–H ◊ ◊ ◊ Br, I hydrogen bonds into infinite zig-zag chains (N ◊ ◊ ◊ Br,
2
plexes of the type [Cu(k (S,N),m(S)-SN-Ph)(CH3CN)]22+ (11a) and
2
2+
[Cu(k (S,N),m(S)-SN-iPr)(CH3CN)]2 (11b), respectively, which
˚
I 3.447, 3.676 and 3.721 A for 3b, 5b, and 6b, respectively).
feature bridging SN ligands. In the course of this dimerization,
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Table 1 Comparison of selected geometric parameters (A, ◦) of the complexes 3a, 3b, 5b, 6b, 7a, and 7b, with triangular coordination of Cu
˚
E =
X =
Cu–N
Cu–E
Cu–X
N–Cu–E
N–Cu–X
E–Cu–X
CuPD
3a
3b
5b
6b
7a
7b
S
S
S
Se
S
Br
Br
I
I
C
C
2.060
2.026
2.021
2.017
2.048
2.044
2.209
2.205
2.217
2.323
2.267
2.306
2.341
2.327
2.496
2.495
1.913
1.935
113.5
115.2
116.0
117.1
108.8
106.9
111.7
113.4
114.4
115.5
129.2
135.2
133.7
130.3
128.9
127.0
121.6
117.7
0.131
0.100
0.104
0.088
0.075
0.047
S
For convenience, bond lengths and angles were rounded to three and one decimal place, respectively. E = S or Se, X = Br, I, or C of the NHC-ligand.
“CuPD” is the distance of Cu from the N–E–X plane.
Table 2 Comparison of selected geometric parameters (A, ◦) of the dinuclear complexes 11a, 11b, and 12, with tetrahedral coordination about Cu
˚
L =
Cu1–L
Cu1–N1
Cu1–S1
Cu1–S1a
Cu1 ◊ ◊ ◊ Cu1a
S1–Cu1–S1a
S1 ◊ ◊ ◊ S1a
11a
11b
12
N3
N3
C12
1.964
1.966
1.877
2.069
2.096
2.092
2.326
2.298
2.360
2.435
2.411
2.428
2.671
2.871
3.126
111.8
107.7
98.5
3.943
3.802
3.628
For convenience, bond lengths and angles were rounded to three and one decimal place, respectively. L = N3 of an acetonitrile or C12 of a CNtBu ligand.
S1a and Cu1a are the centrosymmetric equivalents of S1 and Cu1.
Scheme 5
one CH3CN ligand was liberated. A similar reaction took place
when iodide abstraction from 10b was performed in the presence
of CNtBu (1 equiv.) as depicted in Scheme 6. NMR monitoring of
this reaction did not provide any evidence for the formation of a
2
monomeric intermediate such as [Cu(k (S,N)-SN-iPr)(CNtBu)2]+.
Even if two or three equiv. of CNtBu were used, only the formation
of the dimeric complex [Cu(k (S,N),m(S)-SN-iPr)(CNtBu)]22+ (12)
2
was observed (Scheme 6).
Scheme 6
Fig. 8 Molecular structure of 11a showing 50% displacement ellipsoids.
Compounds 10, 11, and 12 were again characterized by a
-
SbF6 anion, diethyl ether solvent molecule, and H atoms omitted for
combination of H, 13C{ H}, and 31P{ H} NMR and IR spec-
troscopy and elemental analysis. In addition, 11a, 11b, and 12
were characterized by X-ray crystallography. Structural views
are depicted in Fig. 8–10 with important bond distances and
angles reported in the caption. All three compounds contain
crystallographically centrosymmetric dinuclear complexes with
the copper atoms in modestly distorted tetrahedral coordination
by one pyridine N, two sulfur atoms and a N or C atom of the
ancillary ligand. The two Cu and S atoms form a perfectly planar
rhombus-like parallelogram with two shorter and two longer Cu–
1
1
1
clarity. The molecule is centrosymmetric. Selected distances and angles
(A, ◦): Cu1–N3 1.964(2), Cu1–N1 2.069(2), Cu1–S1 2.3264(5), Cu1–S1A
˚
2.4349(5), Cu1 ◊ ◊ ◊ Cu1A 2.6711(4), P1–S1 1.9943(5), P1–N2 1.6621(14),
N3–Cu1–N1 111.59(6), N3–Cu1–S1 113.12(5), N3–Cu1–S1A 118.98(5),
N1–Cu1–S1 110.14(4), N1–Cu1–S1A 88.58(4), S1–Cu1–S1A 111.792(14),
P1–S1–Cu1 87.49(2), P1–S1–Cu1A 118.96(2).
S bonds. The shorter Cu–S bond subtends with the S–P bond
angle close to 90◦, whereas for the longer Cu–S bond this angle is
between 111 and 119◦. Table 2 gives a comparison of geometric
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In this context it has to be noted that Cu–Cu d10–d10 interactions
have been the subject of many experimental and theoretical studies
due to their biological relevance, e.g., cytochrome oxidase and
hemocyanins contain a Cu(I)–Cu(I) active site.19 However, copper–
˚
copper separations in the range of 2.7–3.6 A are observed for many
complexes of the formula LnCu(m-X)2CuLm (m = 1, 2; n = 1, 2)
which contain X bridges such as halides, alkoxides, and sulfides.
In all these cases, a direct Cu–Cu bond can be excluded as the
˚
separation exceeds by at least 0.3 A the sum of the copper covalent
20
˚
radii (1.17 A).
Halide abstraction from 5b with AgCF3SO3 in THF, followed
by the addition of one equiv. of PPh3, afforded the tetracoordinate
2
1
complex [Cu(k (S,N)-SN-iPr)(PPh3)(k (O)-CF3SO3)] (13) in 51%
isolated yield (Scheme 7). This complex contains a coordinated
CF3SO3 anion. In the 31P{ H} NMR spectrum, the SN-iPr and
PPh3 ligands give rise to singlets at 91.1 and 11.8 ppm, respectively
(for comparison, the free ligands exhibit resonances at 103.5 and
-6.5 ppm).
-
1
Fig. 9 Molecular structure of 11b showing 50% displacement ellipsoids.
-
SbF6 anion and H atoms omitted for clarity. The molecule is cen-
trosymmetric. Selected distances and angles (A, ◦): Cu1–N3 1.9661(14),
˚
Cu1–N1 2.0957(11), Cu1–S1 2.2984(5), Cu1–S1A 2.4110(4), Cu1 ◊ ◊ ◊ Cu1A
2.7810(5), P1–S1 2.0032(5), P1–N2 1.6735(12), N3–Cu1–N1 103.08(5),
N3–Cu1–S1 122.28(4), N3–Cu1–S1A 118.77(4), N1–Cu1–S1 109.16(4),
N1–Cu1–S1A 90.42(3), S1–Cu1–S1A 107.655(14), P1–S1–Cu1 91.37(2),
P1–S1–Cu1A 112.04(2).
Scheme 7
A structural view of 13 is shown in Fig. 11 with selected
bond distances and angles reported in the caption. Copper has
a distorted tetrahedral coordination by each one N, P, S, and O
atom with bond angles between 90 and 133◦. As the Cu1–O1
bond is clearly the longest and weakest of the four bonds, the
coordination of this Cu is not far off a flat triangular one with the
˚
metal atom only 0.340 A above the plane of the N–P–S triangle
Fig. 10 Molecular structure of 12 showing 50% displacement ellip-
-
soids. SbF6 anion, diethyl ether solvent molecule, and H atoms omit-
ted for clarity. The molecule is centrosymmetric. Selected distances
and angles (A, ◦): Cu1–C12 1.8873(12), Cu1–N1 2.0924(10), Cu1–S1
˚
2.3598(3), Cu1–S1A 2.4280(3), Cu1 ◊ ◊ ◊ Cu1A 3.1255(3), P1–S1 1.9971(4),
P1–N2 1.6736(9), C12–Cu1–N1 117.98(5), C12–Cu1–S1 117.99(4),
C12–Cu1–S1A 121.66(4), N1–Cu1–S1 106.17(3), N1–Cu1–S1A 89.63(3),
S1–Cu1–S1A 98.51(1), P1–S1–Cu1 91.46(1), P1–S1–Cu1A 111.25(1).
Fig. 11 Molecular structure of 13 showing 50% displacement ellipsoids.
H atoms omitted for clarity. Selected distances and angles (A, ◦):
˚
data revealingthat these complexes, despite their generalgeometric
uniformity, exhibit a large variation in the intramolecular Cu–Cu
Cu1–N1 2.0261(13), Cu1–P2 2.2099(4), Cu1–O1 2.2395(14), Cu1–S1
2.3101(4), P1–S1 1.9756(5), P1–N2 1.6870(14), N1–Cu1–P2 132.86(4),
N1–Cu1–O1 90.06(6), N1–Cu1–S1 109.84(4), P2–Cu1–O1 99.03(4),
P2–Cu1–S1 109.71(2), O1–Cu1–S1 110.71(5), P1–S1–Cu1 92.25(2).
˚
˚
˚
distance, ranging from 2.671 A in 11a to 2.781 A in 11b and 3.126 A
in 12.
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Scheme 8
˚
(expected elevation in a regular tetrahedron is about 0.7 A). The
likely monomeric. This may be attributed to the higher steric
demand of h -coordinated terminal alkynes as compared to the
2
NH group of this complex forms a hydrogen bond to O2 of a
neighboring complex (N2 ◊ ◊ ◊ O2 = 2.877(2) A) linking them into
˚
terminally coordinated ligands CH3CN and CNtBu, respectively,
where dimeric structures were formed. Moreover, it has to be
noted that, in principle, the alkyne ligands can be coordinated
in two conformations where the internal alkyne carbon atom is
either in a trans or cis position with respect to the S atom of
the SN-iPr ligand. The free energy of the two rotamers of 14a
and 14b (shown for 14b in Fig. 12) is nearly the same, differing
only by 0.6 kcal mol-1 in both cases. The free activation energies
(DG‡) for alkyne rotation were calculated to be 15.1 and 17.9 kcal
mol-1, respectively, which is consistent with free rotation of the
linear chains.
Halide abstraction from 5b with AgSbF6 (1 equiv.) in
THF was also performed in the presence of the terminal
alkynes HC CC6H4Me and HC CC6H4OMe yielding cop-
2
per(I) alkyne complexes of the tentative formula [Cu(k (S,N)-
SN-iPr)(h -HC CC6H4Me)]+ (14a) and [Cu(k (S,N)-SN-iPr)(h -
HC CC6H4OMe)]+ (14b), respectively, as shown in Scheme 8. It
has to be noted that complex 5b did not undergo a reaction with
olefins and carbon monoxide under the same reaction conditions.
The exact structure of 14a and 14b could not be fully established,
since we were unable to obtain single crystals suitable for an
X-ray analysis. Thus, merely based on NMR spectroscopic
data we cannot exclude that these complexes are dimeric
(vide infra).
2
2
2
2
C–C bonds of the h -bound alkyne ligand at room temperature.
For comparison, the energy barrier (DG‡) for alkyne rotation
4
2
2
in the tetrameric Cu(I) alkyne complexes [Cu4-m -O-m -X2(h -
tmtch)4] (tmtch = 3,3,6,6-tetramethyl-1-thia-4-cycloheptyne, X =
Cl, Br) was experimentally determined to be 13.4 and 12.9 kcal
mol-1, respectively. Similarly, the energy barrier for alkyne rotation
1
The H NMR spectra of 14a and 14b in CD2Cl2 exhibits a
2
singlet corresponding to the HC C– moiety of the alkynes at 4.68
ppm, which is a downfield shift compared to the corresponding
signals of the free HC CC6H4Me and HC CC6H4OMe alkynes
(3.56 and 3.49 ppm). The resonances of the acetylenic carbon
in the b-diketiminato complex [Cu(Me3NN)(h -HC CPh)] was
determined to be 13.4 kcal mol-1. These data correspond to fast
rotation at room temperature.23,24 In the transition state, TSrot,
the alkyne has rotated roughly by about 90◦ around the axis,
connecting the Cu to the C C centroid. The Cu–C bond to the
2
atoms are barely shifted upon h -coordination of the C C triple
˚
bond to the copper(I) center, which is a common observation in
internal alkyne carbon atom is significantly elongated from 2.12 A
alkyne–copper(I) chemistry.21,22 In the case of 14a, the 13C{ H}
in 14a to 2.55 A in TSrot, while the Cu–C bond to the terminal
1
˚
˚
NMR signals of the terminal and internal acetylenic carbons
HC C– and HC C–in acetone-d6 appear at 79.2 and 87.9 ppm,
respectively, which is slightly downfield shifted relative to the free
ligand which gave rise to signals at 77.6 and 83.5 ppm (DFT
calculated shift values for the free ligand: 75.5 and 80.8 ppm; for
alkyne carbon atom has changed only from 1.96 to 1.99 A.
Conclusion
complex 14a: 80.8 and 108.9 ppm). Concurrent 13C{ H} NMR
1
In this work we have synthesized a series of tri- and tetra-
coordinated copper(I) complexes with the EN ligands N-(2-
pyridinyl)amino-diphenylphosphine sulfide, N-(2-pyridinyl)-
amino-diisopropylphosphine sulfide, N-(2-pyridinyl)amino-
diphenylphosphine selenide, N-(2-pyridinyl)amino-diisopro-
pylphosphine selenide by using the copper(I) precursors CuX (X =
Br, I), [Cu(IPr)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-
2-ylidene), and [Cu(CH3CN)4]PF6. Several mononuclear tri- and
tetracoordinate complexes could be obtained. In some cases,
it was found that SN ligands are capable of acting as bridging
ligands, thereby forming dinuclear complexes. Terminal alkynes
spectra were observed for 14b giving signals at 78.5 and 88.5
ppm, respectively, for the terminal and internal acetylenic carbons
atoms (calculated shift values: 80.4 and 111.3 ppm). Accordingly,
the room temperature NMR spectra are consistent with rapid
spinning of the alkyne around the axis connecting the Cu to the
C
C centroid on the NMR time scale (vided infra).
In order to obtain further information of the structure
of complexes 14, DFT calculations were carried out with
2
the monomeric and dimeric model complexes [Cu(k (S,N)-
SN-iPr)(h -HC CC6H5)]+ and [Cu(k (S,N),m(S)-SN-iPr)(h -
HC CC6H5)]22+, respectively. Interestingly, the dimeric complex
featuring bridging SN-iPr ligands turned out to be unstable at
this level of theory and spontaneous monomerization took place.
Accordingly, these results suggest that complexes 14 are most
2
2
2
2
were found to react with the [Cu(k (S,N)-SN-iPr)]+ fragment to
2
2
form complexes of the type [Cu(k (S,N)-SN-iPr)(h -alkyne)]+.
The mononuclear nature of these compounds was supported by
DFT calculations.
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2
2
Fig. 12 Free energy profile for the rotation of the HC CC6H4OMe ligand in [Cu(k (S,N)-SN-iPr)(h -HC CC6H4OMe)]+ (14b) (experimental and
calculated (italic) 1H and 13C NMR chemical shifts d in ppm relative to TMS).
Ph2,6), 128.6 (d, JCP = 13.4 Hz, Ph3,5), 117.0 (◦s, py5), 112.1 (d, JCP
=
Experimental Section
1
3.4 Hz, py3). 31P{ H} NMR (d, CD2Cl2, 20 C): 64.4.
General
N-(2-pyridinyl)amino-diisopropylphosphine sulfide (SN-iPr) (1b)
All manipulations were performed under an inert atmo-
sphere of argon by using Schlenk techniques. The solvents
were purified according to standard procedures.25 The lig-
ands N-diphenylphosphino-2-aminopyridine (PN-Ph) and N-
diisopropylphosphino-2-aminopyridine (PN-iPr),2 and the cop-
per(I) precursors [Cu(CH3CN)4]PF6,26 and Cu(IPr)Cl (IPr = 1,3-
bis(2,6-diisopropylphenyl)imidazol-2-ylidene)27 were prepared ac-
cording to the literature. The deuterated solvents were purchased
This ligand has been prepared analogously to 1a with PN-iPr
(1.68 g, 8.0 mmol) and elemental sulphur (256 mg, 8.0 mmol)
1
as starting materials. Yield: 1.56 g (80%). H NMR (d, CDCl3,
◦
20 C): 8.08 (d, J = 4.3 Hz, py6), 7.48 (t, J = 7.6 Hz, py4), 6.76
(m, 2H, py3,5), 5.33 (s, NH), 3.11–2.91 (dh, J = 2.0 Hz, J = 6.9 Hz,
1
2H, CH(CH3)2), 1.32–1.09 (m, 12H, CH(CH3)2). 13C{ H} NMR
◦
(d, CDCl3, 20 C): 154.5 (s, py2), 147.6 (s, py6), 138.0 (s, py4),
from Aldrich and dried over 4 A molecular sieves. H, 13C{ H},
116.2 (s, py5), 110.9 (d, JCP = 5.7 Hz, py3), 29.22 (d, JCP = 58.6 Hz,
CH(CH3)2), 17.1 (s, CH(CH3)2), 16.6 (d, JCP = 2.7 Hz, CH(CH3)2).
1
1
˚
and 31P{ H} NMR spectra were recorded on Bruker AVANCE-
1
◦
1
250 and AVANCE-300 DPX spectrometers and were referenced to
SiMe4 and H3PO4 (85%), respectively. The 15N NMR parameters
31P{ H} NMR (d, CDCl3, 20 C): 104.6.
were obtained through H–15N HMBC (heteronuclear multiple
1
N-(2-pyridinyl)amino-diphenylphosphine selenide (SeN-Ph) (2a)
bond correlation) and 1H–15N HMQC (heteronuclear single
quantum coherence) experiments and are referenced to NH4Cl. 1H
This ligand has been prepared according to literature11a with PN-
Ph (100 mg, 0.36 mmol) and gray selenium (28.4 mg, 0.36 mmol)
as starting materials. Yield: 70 mg (55%). 1H NMR (d, acetone-d6,
and 13C NMR signal assignments were confirmed by H-COSY,
1
135-DEPT, 1H-13C HMQC and 1H-13C HMBC experiments.
◦
20 C): 8.10–7.92 (m, 5H, Ph, py6), 7.55–7.40 (m, 7H, Ph, py4),
7.03 (d, J = 8.21 Hz, 1H, py3), 7.00 (t, J = 5.84 Hz,◦1H, py5),
1
7.37 (bs, 1H, NH). 13C{ H} NMR (d, acetone-d6, 20 C): 154.6
N-(2-pyridinyl)amino-diphenylphosphine sulfide (SN-Ph) (1a)
(d, JCP = 3.0 Hz, py), 147.2 (s, py), 137.3 (s, py), 131.9 (d, JCP
=
This ligand has been prepared according to literature11a with PN-
Ph (1.0 g, 3.5 mmol) and elemental sulphur (115 mg, 3.5 mmol)
as starting materials. The crude product was purified by recrystal-
lization from a 1 : 1 mixture of Et2O–THF. Yield: 556 mg (86%).
1H NMR (d, CD2Cl2, 20 ◦C): 8.18–7.95 (m, 4H, Ph), 7.81 (d, J =
4.5 Hz, py6), 7.61–7.33 (m, 7H, Ph, py4), 7.28 (s, NH), 6.91 (d, J =
12.2 Hz, Ph), 131.7 (d, JCP = 12.3 Hz, Ph), 128.2 (d, JCP = 13.8 Hz,
1
Ph), 116.4 (s, py), 112.4 (d, JCP = 6.1 Hz, py). 31P{ H} NMR (d,
acetone-d6, 20 ◦C): 58.3 (with satellites JP–Se = 787 Hz).
N-(2-pyridinyl)amino-diisopropylphosphine selenide (SeN-iPr)
(2b)
1
8.3 Hz, py3), 6◦.73 (dd, J = 5.2 Hz, J = 7.1 Hz, py5). 13C{ H} NMR
(d, CDCl3, 20 C): 153.7 (s, py2), 147.9 (s, py6), 137.4 (s, py4), 133.5
(d, JCP = 115.2 Hz, Ph1), 132.0 (s, Ph4), 131.6 (d, JCP = 11.4 Hz,
This ligand has been prepared analogously to 2a with PN-iPr
(1.0 g, 4.50 mmol) and gray selenium (375.5 mg, 4.50 mmol) as
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◦
1
1
starting materials. Yield: 1.16 g (89%). H NMR (d, acetone-d6,
H, 4.41; N, 6.27%. H NMR (d, acetone-d6, 20 C): 8.49 (d, J =
4.11 Hz, 1H, py6), 7.77 (t, J = 7.11 Hz, 1H, py4), 7.60 (bs,1H, NH),
7.10 (d, J = 8.21 Hz, 1H, py3), 7.01 (t, J = 6.21 Hz, 1H, py5), 2.82
◦
20 C): 8.13 (d, J = 4.11 Hz, 1H, py6), 7.70 (t, J = 7.42 Hz, 1H,
py4), 7.05 (d, J = 8.21 Hz, 1H, py3), 6.84 (t, J = 6.00 Hz, 1H,
py5), 6.75 (bs, 1H, NH), 7.19 (m, 2H, CH(CH3)2), 1.24–0.99 (m,
(m, 2H, CH(CH3)2), 1.30 (m, 12H, CH(CH3)2). 31P{ H} NMR (d,
1
◦
12H, CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 C): 155.5 (d,
J = 6.1 Hz, py), 147.2 (s, py), 138.0 (s, py), 115.9 (s, py), 111.4
(d, JCP = 7.3 Hz, py), 28.6 (d, JCP = 49.0 Hz, CH(CH3)2), 17.5 (s,
acetone-d6, 20 ◦C): 82.2 (with satellites JP-Se = 688 Hz).
[Cu(j2(S,N)-SN-Ph)I] (5a)
1
CH(CH3)2), 16.6 (d, J = 3.0 Hz, CH(CH3)2. 31P{ H} NMR (d,
1
acetone-d6, 20 ◦C): 102.0 (with satellites JP-Se = 752 Hz).
[Cu(j2(S,N)-SN-Ph)Br] (3a)
This complex has been prepared analogously to 3a with CuI
(123 mg, 0.65 mmol) and SN–Ph (200 mg, 0.65 mmol) as starting
materials. Yield: 277 mg (85%). Anal. Calcd. for C17H15CuIN2PS:
C, 40.77; H, 3.02; N, 5.59%. Found: C, 40.63; H, 2.92; N, 5.46%.
◦
◦
1
A solution of CuBr (183 mg, 1.28 mmol) and SN-Ph (396 mg,
1.28 mmol) in THF (15 mL) was stirred for 12 h at room
temperature. After that, the insoluble materials were removed by
filtration and the solvent was removed under reduced pressure. The
remaining product was washed twice with diethyl ether (10 mL)
and dried under vacuum. Yield: 462 mg (80%). Anal. Calcd. for
C17H15BrCuN2PS: C, 44.99; H, 3.33; N, 6.83%. Found: C, 45.14;
H, 3.40; N, 6.70%. 1H NMR (d, acetone-d6, 20 ◦C): 8.19 (bs, 1H,
NH), 8.02 (s,1H, py6), 7.99–7.80 (m, 4H, Ph), 7.84 (t, J = 7.57 Hz,
1H, py4), 7.67–7.58 (m, 6H, Ph), 7.29 (d, J = 8.15 Hz, 1H, py3), 6.96
M.P.: 214 C. HNMR (d, acetone-d6, 20 C): 8.30 (s, 1H, py6),
8.00–7.94 (m, 4H, Ph), 7.84 (s, 1H, py4), 7.59 (s, 6H, Ph), 7.55 (bs,
1H, NH), 7.29 (d, J = 8.15◦Hz, 1H, py3), 7.00 (s, 1H, py5). 13C{ H}
1
NMR (d, acetone-d6, 20 C): 154.4 (d, JCP = 3.0 Hz, py), 149.8
(s, py), 140.1 (s, py), 133.0 (d, JCP = 3.0 Hz, Ph), 131.7 (d, JCP
=
12.2 Hz, Ph), 130.5 (d, JCP = 32.2 Hz, Ph), 129.0 (d, JCP = 13.8 Hz,
Ph), 117.61 (s, py), 115.4 (d, JCP = 6.1 Hz, py). 31P{ H} NMR (d,
1
acetone-d6, 20 ◦C): 50.7.
[Cu(j2(S,N)-SN-iPr)I] (5b)
◦
(t, J = 6.53 Hz, 1H, py5). 13C{ H} NMR (d, acetone-d6, 20 C):
1
This complex has been prepared analogously to 3a with CuI
(1.37 g, 8.24 mmol) and SN-iPr (2.0 g, 8.24 mmol) as starting
materials. Yield: 3.15 g (89%). Anal. Calcd. for C11H19CuIN2PS:
C, 30.53; H, 3.80; N, 6.47%. Found: C, 3◦0.61; H, 3.89; N, 6.56%.
M.P.: 147 ◦C. 1H NMR (d, acetone-d6, 20 C): 8.48 (d, J = 5.17 Hz,
1H, py6), 7.76 (t, J = 7.90 Hz, 1H, py4), 7.52 (bs, 1H, NH), 7.10
(d, J = 8.50 Hz, 1H, py3), 7.02 (t, J = 6.32 Hz, 1H, py5), 2.76 (m,
154.4 (d, JCP = 4.6 Hz, py), 149.0 (s, py), 140.1 (s, py), 133.1 (s, Ph),
131.5 (d, JCP = 12.4 Hz, Ph), 130.1 (d, JCP = 38.2 Hz, Ph), d, JCP
=
13.8 Hz, Ph), 117.6 (s, py), 115.3 (d, JCP = 7.67 Hz, py). 31P{ H}
1
NMR (d, acetone-d6, 20 ◦C): 49.8.
[Cu(j2(S,N)-SN-iPr)Br] (3b)
1
This complex has been prepared analogously to 3a with CuBr
(296 mg, 2.06 mmol) and SN-iPr (500 mg, 2.06 mmol) as starting
materials. Yield: 540 mg (68%). Anal. Calcd. for C11H19BrCuN2PS:
C, 34.25; H, 4.96; N, 7.26%. Found: C, 34.30; H, 4.80; N, 7.12%. 1H
NMR (d, acetone-d6, 20 ◦C): 8.43 (s, 1H, py6), 7.78 (t, J = 7.01 Hz,
1H, py4), 7.62 (bs, 1H, NH), 7.11–7.03 (m, 2H, py3,5), 2.73 (m,
2H, CH(CH3)2), 1.39–1.23 (m, 12H, CH(CH3)2). 13C{ H} NMR
(d, acetone-d6, 20 ◦C): 155.5 (d, JCP = 4.4 Hz, py2), 149.6 (s, py6),
139.8 (s, py4), 117.2 (s, py5), 114.8 (d, JCP = 4.99 Hz, py3), 29.5 (d,
JCP = 54.3 Hz, CH(CH3)2), 16.3 (d, JCP = 2.49 Hz, CH(CH3)2),
◦
15.6 (s, CH(CH3)2). 31P{ H} NMR (d, acetone-d6, 20 C): 89.3.
1
2H, CH(CH3)2), 1.41–1.25 (m, 12H, CH(CH3)2). 13C{ H} NMR
1
[Cu(j2(Se,N)-SeN-Ph)I] (6a)
(d, acetone-d6, 20 ◦C): 155.5 (d, JCP = 4.4 Hz, py2), 148.7 (s, py6),
139.8 (s, py4), 117.2 (s, py5), 114.6 (d, JCP = 5.00 Hz, py3), 29.5 (d,
JCP = 54.3 Hz, CH(CH3)2), 16.3 (s,◦CH(CH3)2), 15.6 (s, CH(CH3)2).
This complex has been prepared analogously to 3a with CuI
(106 mg, 0.56 mmol) and SeN-Ph (200 mg, 0.56 mmol) as starting
materials. Yield: 210 mg (69%). Anal. Calcd. for C17H15CuIN2PSe:
C, 37.25; H, 2.76; N, 5.11%. Found: C, 37.15; H, 2.80; N, 5.20%.
31P{ H} NMR (d, acetone-d6, 20 C): 86.7.
1
◦
1H NMR (d, acetone-d6, 20 C): 8.01 (d, J = 5.34 Hz, 1H, py6),
[Cu(j2(Se,N)-SeN-Ph)Br] (4a)
7.97–7.76 (m, 5H, Ph), 7.64 (t, J = 7.28 Hz, 1H, py4), 7.60–7.57 (m,
6H, Ph, NH), 7.27 (d, J = 8.21 Hz, 1H, py3◦), 6.98 (t, J = 5.83 Hz,
This complex has been prepared analogously to 3a with CuBr
(40 mg, 0.280 mmol) and SeN-Ph (100 mg, 0.280 mmol)
as starting materials. Yield: 120 mg (85%). Anal. Calcd. for
C17H15CuBrN2PSe: C, 40.78; H, 3.02; N, 5.59%. Found: C, 40.69;
1H, py5). 13C{ H} NMR (d, acetone-d6, 20 C): 154.2 (s, py), 150.0
1
(s, py), 139.9 (s, py), 132.9 (d, JCP = 3.0 Hz, Ph), 131.8 (d, JCP
=
12.2 Hz, Ph), 130.4 (d, JCP = 38.3 Hz, Ph), 129.0 (d, JCP = 13.8 Hz,
◦
1
1
H, 3.12; N, 5.46%. H NMR (d, acetone-d6, 20 C): 8.21 (s, 1H,
py6), 8.01–7.92 (m, 4H, Ph), 7.90 (t, J = 7.42 Hz, 1H, py4), 7.66–
7.49 (m, 7H, NH, Ph), 7.28 (d, J = 8.53 Hz, 1H, py3), 6.96 (t, J =
Ph), 117.4 (s, py), 115.5 (d, JCP = 6.1 Hz, py). 31P{ H} NMR (d,
acetone-d6, 20 ◦C): 42.3 (with satellites JP–Se = 698 Hz).
[Cu(j2(Se,N)-SeN-iPr)I] (6b)
◦
5.84 Hz, 1H, py5). 31P{ H} NMR (d, acetone-d6, 20 C): 53.3 (with
1
satellites JP–Se = 693 Hz).
This complex has been prepared analogously to 3a with CuI
(198 mg, 1.04 mmol) and SeN-iPr (301 mg, 1.04 mmol) as starting
materials. Yield: 370 mg (75%). Anal. Calcd. for C11H19CuIN2PSe:
C, 27.54; H, 3.99; N, 5.84%. Found: C, 27.44; H, 4.12; N, 6.06%.
1H NMR (d, acetone-d6, 20 ◦C): 8.49 (d, J = 5.05 Hz, 1H, py6), 7.78
(t, J = 7.74 Hz, 1H, py4), 7.52 (bs, 1H, NH), 7.17 (d, J = 8.21 Hz,
1H, py3), 7.02 (t, J = 6.16 Hz, 1H, py5), 2.90 (m, 2H, CH(CH3)2),
[Cu(j2(Se,N)-SeN-iPr)Br] (4b)
This complex has been prepared analogously to 3a with CuBr
(262 mg, 1.83 mmol) and SeN-iPr (528 mg, 1.83 mmol) as
starting materials. Yield: 670 mg (85%). Anal. Calcd. for
C11H19BrCuN2PSe: C, 30.54; H, 4.43; N, 6.74%. Found: C, 30.47;
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◦
1
1.27 (m, 12H, CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 C):
149.5 (s, py), 139.6 (s, py), 117.0 (s, py), 114.4 (d, JCP = 4.4 Hz,
py), 29.8 (d, JCP = 48.8 Hz, CH(CH3)2), 16.3 (s, CH(CH3)2), 16.2
13.8 Hz, Ph), 131.0 (d, JCP = 113.4 Hz, Ph), 117.7 (s,◦py), 115.3 (d,
1
JCP = 6.1 Hz, py). 31P{ H} NMR (d, acetone-d6, 20 C): 52.8.
◦
(s, CH(CH3)2). 31P{ H} NMR (d, acetone-d6, 20 C): 84.6 (with
1
[Cu(j2(S,N)-SN-iPr)2]PF6 (8b)
satellites JP-Se = 684 Hz).
This complex has been prepared analogously to 8a with
[Cu(CH3CN)4]PF6 (154 mg, 0.41 mmol) and SN-iPr (200 mg,
0.82 mmol) as starting materials. Yield: 171 mg (60%). Anal.
Calcd. for C22H38CuF6N4P3S2: C, 38.12; H, 5.53; N, 8.08%. Found:
C, 38.21; H, 5.62; N, 8.12%. 1H NMR (d, acetone-d6, 20 ◦C): 8.09
(d, J = 4.42 Hz, 2H, py6), 7.66(t, J = 7.13 Hz, 2H, py4), 7.30 (bs,
2H, NH), 7.05 (d, J = 8.15 Hz, 2H, py3), 6.86 (t, J = 5.84 Hz, 2H,
[Cu(j2(S,N)-SN-Ph)(IPr)]SbF6 (7a)
A solution of [Cu(IPr)Cl] (100 mg, 0.20 mmol) in THF (20 mL)
was treated with SN–Ph (64 mg, 0.20 mmol) and AgSbF6 (70 mg,
0.20 mmol) and the mixture was stirred for 12 h at room
temperature. Insoluble materials were removed by filtration and
the solvent was then removed under reduced pressure. The product
was washedwith diethylether (2 ¥ 10mL)and driedunder vacuum.
Yield: 155 mg (78%). Anal. Calcd. for C44H51CuF6N4PSSb: C,
52.94; H, 5.15; N, 5.61%.◦Found: C, 52.80; H, 5.31; N, 5.66%. 1H
NMR (d, acetone-d6, 20 C): 8.55 (bs, 1H, py6), 7.74 (s, 2H, IPr),
7.71–7.50 (m, 3H, IPr, py4), 7.45–7.42 (d, J = 7.89 Hz, 4H, IPr),
7.19 (d, J = 7.89 Hz, 1H, NH), 6.61 (bs, 1H, py3), 6.39 (bs, 1H,
py5), 2.73–2.70 (m, 4H, CH(CH3)2), 1.26–0.9 (m, 24H, CH(CH3)2).
1
py5), 2.90 (m, 4H, CH(CH3)2), 1.29 (m, 24H, CH(CH3)2). 13C{ H}
◦
NMR (d, acetone-d6, 20 C): 155.8 (d, JCP = 6.13 Hz, py), 147.7
(s, py), 149.5 (s, py), 117.3 (s, py), 114.8 (d, JPC = 4.6 Hz, py),
29.5 (d, JCP = 33.7 Hz, CH(CH3)2), 16.2 (s, CH(CH3)2), 15.40 (s,
◦
1
CH(CH3)2). 31P{ H} NMR (d, acetone-d6, 20 C): 92.9.
[Cu(j2(Se,N)-SeN-Ph)2]PF6 (9a)
◦
1
13C{ H} NMR (d, acetone-d6, 20 C): 183.1 (s, IPr), 156.0 (s, py),
This complex has been prepared analogously to 8a with
[Cu(CH3CN)4]PF6 (104.3 mg, 0.28 mmol) and SeN-Ph (200 mg,
0.56 mmol) as starting materials. Yield: 200 mg (78%). Anal.
Calcd. for C34H30CuF6N4P3Se2: C, 44.24; H, 3.28; N, 6.07%.
149.9 (s, py),145.7 (s, IPr), 140.7 (s, py), 133.0 (d, JCP = 3.0 Hz,
Ph), 131.7 (d, JCP = 12.2 Hz, Ph), 130.3 (s, Ph), 129.0 (d, JCP
13.8 Hz, Ph), 124.7 (s, IPr), 124.3 (s, IPr), 124.1 (s, IPr), 117.7 (s,
=
1
Found: C, 44.18; H, 3.12; N, 6.16%. H NMR (d, acetone-d6,
py), 116.5 (s, py), 28.5 (s, IPr), 23.6 (s,◦IPr), 23.4 (s, IPr), 22.8 (s,
◦
1
IPr). 31P{ H} NMR (d, acetone-d6, 20 C): 55.2.
20 C): 7.99–7.73 (m, 10H, Ph, py), 7.67–7.58 (m, 16H, Ph, py),
1
7.26 (d, 2H, J = 8.01 Hz, py), 6.73 (t, J = 5.87 Hz, 2H, py). 13C{ H}
◦
[Cu(j2(S,N)-SN-iPr)(IPr)]SbF6 (7b)
NMR (d, acetone-d6, 20 C): 154.7 (d, JCP = 3.0 Hz, py), 148.0
(s, py), 139.7 (s, py), 132.9 (d, JCP = 12.2 Hz, Ph), 131.9 (d, JCP
=
This complex has been prepared analogously to 7a with
[Cu(IPr)Cl] (100 mg, 0.17 mmol), SN-iPr (42 mg, 0.17 mmol),
and AgSbF6 (60 mg, 0.17 mmol) as the starting materials. Yield:
100 mg (63%). Anal. Calcd. for C38H55CuF6N4PSSb: C, 49.07; H,
12.2 Hz, Ph), 130.6 (d, JCP = 35.6 Hz, Ph), 129.0 (d, JCP = 13.8 Hz,
1
Ph), 117.4 (s, py), 115.6 (d, JCP = 6.1 Hz, py). 31P{ H} NMR (d,
acetone-d6, 20 ◦C): 44.8 (with satellites JP-Se = 694 Hz).
[Cu(j2(Se,N)-SeN-iPr)2]PF6 (9b)
1
5.96; N, 6.02%. Found: C, 49.25; H, 5.65; N, 6.76%. H NMR
(d, acetone-d6, 20 ◦C): 8.43 (s, 1H, Py6), 7.74 (s, 2H, IPr), 7.71 (t,
J = 8.79 Hz, 1H, py4), 7.58 (t, J = 7.91 Hz, 2H, IPr), 7.51 (d, J =
7.69 Hz, 4H, IPr), 7.24 (d, J = 7.69 Hz, 1H, NH), 7.02 (d, J =
8.35 Hz, 1H, py3), 7.00 (t, J = 6.15 Hz, 1H, py5), 2,81–2.75 (m,
4H, CH(CH3)2), 2.53–2.50 (m, 2H, CH(CH3)2), 1.26–0.9 (m, 36H,
This complex has been prepared analogously to 8a with
[Cu(CH3CN)4]PF6 (200 mg, 0.70 mmol) and SeN-iPr (129 mg,
0.35 mmol) as starting materials. Yield: 200 mg (72%). Anal.
Calcd. for C22H38CuF6N4P3Se2: C, 33.58; H, 4.87; N, 7.12%.
1
CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 ◦C): 183.3 (IPr),
1
Found: C, 33.66; H, 4.65; N, 7.00%. H NMR (d, acetone-d6,
◦
20 C): 8.14 (d, J = 5.37 Hz, 2H, py6), 7.70 (t, J = 7.90 Hz, 2H,
156.0 (s, py), 149.0 (s, py), 145.7 (IPr), 140.3 (IPr), 135.8 (s, py),
130.2 (IPr), 124.2 (IPr), 124.0 (IPr), 117.8 (s, py), 111.3 (s, py),
29.3 (d, JCP = 58.3 Hz, CH(CH3)2), 28.6 (IPr), 23.8 (IPr), 23.2
py4), 7.50 (bs, 2H, NH), 7.07 (d, J = 8.21 Hz, 2H, py3), 6.87 (t,
J = 6.48 Hz, 2H, py5), 2.90 (m, 4H, CH(CH◦3)2), 1.34 (m, 24H,
1
CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 C): 155.5 (d, JCP
=
=
1
(IPr), 15.5 (IPr), 15.1 (CH(CH3)2). 31P{ H} NMR (d, acetone-d6,
20 ◦C): 88.9.
4.6 Hz, py), 148.0 (s, py), 139.5 (s, py), 117.3 (s, py), 115.1(d, JCP
6.1 Hz, py), 29.6 (d, Jcp = 50.6 Hz, CH(CH3)2), 16.7 (s, CH(CH3)2),
15.6 (s, CH(CH3)2). 31P{ H} NMR (d, acetone-d6, 20 ◦C): 83.7
1
[Cu(j2(S,N)-SN-Ph)2]PF6 (8a)
(with satellites JP-Se = 673 Hz).
To a solution of [Cu(CH3CN)4]PF6 (200 mg, 0.537 mmol) in THF
(20 mL) SN-Ph (333 mg, 1.074 mmol) was added and the mixture
was stirred for 12 h at room temperature. After that the solvent
was removed under reduced pressure. The remaining product was
washed twice with diethyl ether (10 mL) and dried under vacuum.
Yield: 350 mg (78%). Anal. Calcd. for C34H30CuF6N4P3S2: C,
27.54; H, 3.99; N, 5.84%. Found: C, 27.45; H, 3.75; N, 5.71%.
[Cu(j2(S,N)-SN-Ph)(NCCH3)2]SbF6 (10a)
A solution of 4a (649 mg, 1.43 mmol) and AgSbF6 (491 mg
(1.43 mmol) in CH3CN (15 mL) was stirred for 2 h at room
temperature. Insoluble materials (AgI) were removed by filtration
and the solvent was then removed under reduced pressure and
the product was washed with diethyl ether (2 ¥ 10 mL) and
dried under vacuum. Yield: 593 mg (60%). Anal. Calcd. for
C21H21CuF6N4PSSb: C, 36.46; H, 3.06; N, 8.10%.◦Found: C, 36.55;
◦
1H NMR (d, acetone-d6, 20 C): 8.53 (s, 2H, py), 7.98–7.92 (m,
8H, Ph, py), 7.64–7.63 (m, 16H, Ph, NH), 7.25 (d, J = 8.21 Hz, 2H,
1
py3), 6.76 (t, J = 5.37 Hz, 2H, py5). 13C{ H} NMR (d, acetone-d6,
20 ◦C): 154.0 (d, JCP = 3.0 Hz, py), 147.8 (s, py), 139.4 (s, py), 133.0
H, 3.12; N, 8.01%. H NMR (d, acetone-d6, 20 C): 8.71 (s, 1H,
1
(d, JCP = 3.0 Hz, Ph), 131.7 (d, JCP = 12.0 Hz, Ph), 129.0 (d, JCP
=
py), 8.00–7.71 (m, 6H, Ph, py), 7.68–7.61 (m, 6H, Ph, NH), 7.36
7018 | Dalton Trans., 2011, 40, 7008–7021
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©

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24H, CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 ◦C): 156.0
(s, py), 149.8 (s, py), 141.5 (s, py), 133.8 (s, C N-), 118.4 (s,
(d, J = 8.21 Hz, 1H, py3), 7.07 (t, J = 6.79 H◦z, 1H, py5), 2.18 (s,
1
1
6H, CH3). 13C{ H} NMR (d, acetone-d6, 20 C): 154.8 (d, JCP
=
4.6 Hz, py), 148.3 (s, py), 140.9 (s, py), 133.4 (d, JCP = 3.1 Hz, Ph),
131.9 (d, JCP = 13.1 Hz, Ph), 131.7 (d, JCP = 12.2 Hz, Ph), 131.5
(s, N C-), 129.3 (d, JCP = 13.8 Hz, Ph), 118.3 (s, py), 116.1 (d,
py), 116.4 (d, JCP = 4.6 Hz, py), 57.6 (s, C(CH3)3), 29.4 (d, JCP
=
55.1 Hz, CH(CH3)2), 29.1 (s, C(CH3)3, 15.7 (s, CH(CH3)2), 15.2
◦
1
(s, CH(CH3)2), 0.6 (CH3). 31P{ H} NMR (d, acetone-d6, 20 C):
◦
1
JCP = 7.67 Hz, py). 31P{ H} NMR (d, acetone-d6, 20 C): 51.8. IR
91.3. IR (ATR, cm-1): 2177 (nC N), 2160 (nC N).
(ATR, cm-1): 2280 (nN C), 2213 (nN C).
[Cu(j2(S,N)-SN-iPr)(PPh3)(j1(O)-CF3SO3)] (13)
[Cu(j2(S,N),l(S)-SN-Ph)(NCCH3)]2(SbF6)2 (11a)
A solution of 4b (300 mg, 0.69 mmol) in THF (15 mL) and
AgCF3SO3 (179 mg, 0.69 mmol) was stirred for 5 min. After that
PPh3 (364 mg (1.38 mmol) was added and the mixture was stirred
for 12 h. Insoluble materials (AgI) were removed by filtration
and the solvent was then removed under reduced pressure and
the product was washed twice with diethyl ether (10 mL) and
dried under vacuum. Yield: 250 mg (51%). Anal. Calcd. for
C30H34CuF3N2O3P2S2: C, 50.24; H, 4.78; N, 3.91%. Found: C,
49.95; H, 4.59; N, 3.79%. Mp: 120.4 ◦C. 1H NMR (d, acetone-d6,
Crystals of 11a were grown by diethyl ether diffusion
into a saturated acetone solution of 10a. Anal. Calcd. for
C38H36Cu2F12N6P2SSb2: C, 35.07; H, 2.79; N, 6.46%. Found: C,
◦
1
35.12; H, 3.50; N, 6.55%. H NMR (d, acetone-d6, 20 C): 8.80
(s, 2H, py), 7.99–7.91 (m, 12H, Ph, py), 7.71 (d, J = 6.63 Hz, 2H,
NH), 7.62 (bs, 10H, Ph), 7.40 (d, J = 7.90 Hz, 2H, py3), 7.08 (t, J =
1
6.32 Hz, 2H, py5), 2.29 (s, 6H, CH3). 31P{ H} NMR (d, acetone-d6,
20 ◦C): 51.6.
◦
20 C): 8.08 (d, J = 5.05 Hz, 1H, py6), 7.99 (bs, 1H, NH), 7.92
(t, J = 7.11 Hz, 1H, py4), 7.52 (d, J = 6.63 Hz,15H, Ph), 7.24 (d,
J = 8.21 Hz, 1H, py3), 7.00 (t, J = 6.48 Hz, 1H, py5), 2.73 (m,
[Cu(j2(S,N)-SN-iPr)(NCCH3)2]SbF6 (10b)
1
2H, CH(CH3)2), 1.38–1.22 (m,12H, CH(CH3)2). 13C{ H} NMR
This complex has been prepared analogously to 10a with 4b (1.0 g,
2.3 mmol) and AgSbF6 (794 mg, 2.30 mmol) as starting materials.
Yield: 750 mg (52%). Anal. Calcd. for C15H25CuF6N4PSSb: C,
28.89; H, 4.04; N, 8.98%.◦Found: C, 28.99; H, 3.91; N, 8.82%. 1H
NMR (d, acetone-d6, 20 C): 8.21 (d, J = 5.37 Hz,1H, py6), 8.10
(d, J = 8.85 Hz, 1H, NH), 7.87 (t, J = 7.74 Hz, 1H, py4), 7.31
(d, J = 8.53 Hz,1H, py3),7.12(t, J = 6.48 Hz, 1H, py5), 2.81–2.74
(m, 2H, CH(CH3)2), 2.23 (s, 6H, NCCH3), 1.40–1.21 (m, 12H,
◦
(d, acetone-d6, 20 C): 156.0 (d, JCP = 4.6 Hz, py), 149.5 (s, py),
141.2 (s, py), 133.5 (d, JCP = 13.8 Hz, Ph), 131.4 (s, Ph), 129.2
(d, JCP = 10.7 Hz, Ph), 118.2 (s, py), 116.7 (d, py, JCP = 4.6 Hz),
29.5 (d, JCP = 58.2 Hz, CH(CH3)2), 15.8 (s, CH(CH3)2), 15.2 (s,
CH(CH3)2). 31P{ H} NMR (d, acetone-d6, 20 ◦C): 91.1 (PiPr2),
1
11.8 (PPh3).
◦
1
CH(CH3)2). 13C{ H} NMR (d, acetone-d6, 20 C): 155.6 (s, py),
[Cu(j2(S,N)-SN-iPr)(g2-HC CC6H4Me)]SbF6 (14a)
148.3 (s, py), 141.2 (s, py), 118.5 (s, py), 116.1 (s, py), 29.6 (d, JCP
=
A solution of 4b (300 mg, 0.69 mmol) in THF (10 mL) was treated
with AgSbF6 (238 mg, 0.69 mmol) and stirred for 5 min. After that,
1-ethynyl-4-metylbenzene (HC CC6H4Me) (483 mg, 4.16 mmol)
was added and the mixture was stirred for 12 h. Insoluble materials
(AgI) were then removed by filtration and the solvent was then
removed under reduced pressure and the product was washed
twice with diethyl ether (10 mL) and dried under vacuum. Yield:
350 mg (77%). Anal. Calcd. for C20H27CuF6N2PSSb: C, 36.52; H,
4.14; N, 4.26%. Found: C, 36.45; H, 4.00; N, 4.36%. 1H NMR (d,
CD2Cl2, 20 ◦C): 7.98 (d, J = 4.65 Hz,1H, py6), 7.87 (t, J = 8.09 Hz,
1H, py4), 7.45 (d, J = 8.08 Hz, 2H, Ph), 7.30 (d, J = 7.78 Hz,
1H, py3), 7.22 (d, J = 7.78 Hz, 2H, Ph), 7.09 (t, J = 6.88 Hz,
1H, py5), 6.56 (d, J = 8.53 Hz, 1H, NH), 4.68 (s, 1H, HC C–),
2.62 (m, 2H, CH(CH3)2), 2.39(s, 3H, C(CH3)) 1.41-1.21(m, 12H,
51.1 Hz, CH(CH3)2), 15.9 (s, CH(CH3)2), 15.3 (s, CH(CH3)2), 1.0
1
(s, CH3). The nitrile carbon atom could not be detected. 31P{ H}
NMR (d, acetone-d6, 20 ◦C): 88.6. IR (ATR, cm-1): 2276 (nN C).
[Cu(j2(S,N),l(S)-SN-iPr)(NCCH3)]2(SbF6)2 (11b)
Crystals of 11b were grown by diethyl ether diffusion
into a saturated acetone solution of 10b. Anal. Calcd. for
C26H44Cu2F12N6P2S2Sb2: C, 26.80; H, 3.81; N, 7.21%. Found: C,
◦
1
26.70; H, 3.92; N, 7.14%. H NMR (d, acetone-d6, 20 C): 8.23
(d, J = 5.05 Hz,2H, py6), 7.89 (t, J = 7.74 Hz, 2H, py4) 7.80 (d,
J = 9.16 Hz, 2H, NH), 7.16 (d, J = 7.58 Hz, 2H, py3), 7.14(t,
J = 5.21 Hz, 2H, py5), 2.78–2.68 (m, 4H, CH(CH3)2), 2.21 (s, 6H,
CH3), 1.40–1.23 (m, 24H, CH(CH3)2). 31P{ H} NMR (d, acetone-
1
d6, 20 ◦C): 88.4.
◦
1
CH(CH3)2). 13C{ H}NMR (d, acetone-d6, 20 C): 155.6 (d, JCP
=
6.1 Hz, py), 148.8 (s, py), 141.3 (s, py), 131.7 (s, Ph), 129.3 (s, Ph),
118.9 (s, py), 117.1 (d, JCP = 4.8 Hz, py), 87.9 (s, HC C-), 79.2 (s,
HC C–), 30.1 (d, JCP = 54.8 Hz, CH(CH3)2), 20.5 (s, Me), 15.9
[Cu(j2(S,N),l(S)-SN-iPr)(CNtBu)]2(SbF6)2 (12)
A solution of 4b (300 mg, 0.69 mmol) in THF (25 mL) and
AgSbF6 (237 mg, 0.69 mmol) was stirred for 5 min. After that
CNtBu (57 mg (0.69 mmol) was added and the mixture was stirred
for 12 h. Insoluble materials (AgI) were removed by filtration
and the solvent was then removed under reduced pressure and
the product was washed twice with diethyl ether (10 mL) and
dried under vacuum. Yield: 380 mg (78%). Anal. Calcd. for
C32H56Cu2F12N6P2S2Sb2: C, 30.76; H, 4.52; N, 6.73%. Found: C,
1
(d, JCP = 3.0 Hz, CH(CH3)2), 15.2 (s, CH(CH3)2). 31P{ H} NMR
(d, acetone-d6, 20 ◦C): 96.0.
[Cu(j2(S,N)-SN-iPr)(g2-HC CC6H4OMe)]SbF6 (14b)
This complex has been prepared analogously to 14a with 4b
(300 mg, 0.69 mmol), AgSbF6 (238 mg, 0.69 mmol), and 1-ethynyl-
4-methoxybenzene (HC C–C6H4OMe) (183 mg, 1.38 mmol)
as starting materials. Yield: 390 mg (84%). Anal. Calcd. for
C20H27CuF6N2OPSSb: C, 35.65; H, 4.04; N, 4.16%. Found: C,
◦
1
30.80; H, 4.47; N, 6.72%. H NMR (d, acetone-d6, 20 C): 8.34
(s, 2H, py6), 7.94–7.91 (m, 4H, NH, py4), 7.22–7.17 (m, 4H, py3,5),
2.70 (m, 4H, CH(CH3)2), 1.59 (s, 18H, C(CH3)3, 1.53–1.20 (m,
◦
1
35.55; H, 3.98; N, 4.24%. H NMR (d, acetone-d6, 20 C): 8.32
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©

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(d, J = 4.87 Hz,1H, py6), 8.31 (d, J = 8.53 Hz, 1H, NH), 7.95
(t, J = 7.01 Hz, 1H, py4), 7.50 (d, J = 8.53 Hz, 2H, Ph), 7.26 (d,
J = 8.53 Hz, 1H, py3), 7.18 (t, J = 6.40 Hz, 1H, py5), 6.97 (d,
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1
2.96 (m, 2H, CH(CH3)2), 1.42–1.21(m, 12H, CH(CH3)2). 13C{ H}
NMR (d, acetone-d6, 20 ◦C): 155.7 (d, JCP = 4.6 Hz, py), 148.9 (s,
py), 141.5 (s, py), 133.3 (s, Ph), 118.8 (s, py), 116.9 (d, JCP = 4.6 Hz,
py), 114.2 (s, Ph), 88.5 (s, HC C–), 78.5 (s, HC C–), 54.8 (s,
OCH3), 30.1 (d, JCP = 55.2 Hz, CH(CH3)2), 15.9 (d, JCP = 3.0 Hz,
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1
CH(CH3)2), 15.2 (s, CH(CH3)2). 31P{ H} NMR (d, acetone-d6,
20 ◦C): 91.5.
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16 H.-G. Henning and U. Ladhoff, Zeitschrift f. Chemie, 1973, 13, 16–17.
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R. Scopelliti and P. J. Dyson, Helv. Chim. Acta, 2003, 86, 3281–3287.
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180; (b) A. Dariki, T. Tsukuda, K. Matsumoto and T. Tsubomura,
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X-ray single crystal data for 1a, 1b, 2a, 2b, 3a, 3b, 5b, 6b,
7a·(CH3)2CO, 7b, 8b, 11a·2(Et2O), 11b, 12·2(Et2O), and 13 were
collected on two Bruker CCD diffractometers (Kappa APEX-
2 and Smart APEX) using graphite-monochromated Mo-Ka
˚
radiation (l = 0.71073 A) and fine-sliced w- and j-scan frames
mostly covering complete spheres of the reciprocal space with
qmax = 30◦ (27.55◦ and 25.96◦ for 3b and 6b, respectively). After
data integration with program SAINT corrections for absorption
and l/2 effects were applied with the program SADABS.28 The
structures were solved by direct methods (SHELXS97) and refined
on F2 with program SHELXL97.29 All non-hydrogen atoms were
refined anisotropically. Most hydrogen atoms were inserted in
idealized positions and were refined riding with the atoms to
which they were bonded. The compounds 1a, 1b and 3b, 5b,
6b, respectively, form two isostructural solid series. Complexes
7a, 11a, and 12 form stoichiometric solvates with well-ordered
solvent molecules (one (CH3)2CO for 7a, two Et2O for 11a and
-
12). Orientation disorder of one iso-propyl group and one SbF6
octahedron was encountered in 7b and 11b, respectively, and was
taken into account. Crystal data and experimental details are given
in Table 3.
CCDC 810363 (for 1a), 810364 (for 1b), 810365 (for 2b),
810366 (for 2b), 810367 (for 3a), 810368 (for 3b), 810369 (for
5b), 810370 (for 6b), 810371 (for 7a·(CH3)2CO)), 810372 (for 7b),
810373 (for 8b), 810374 (for 11a·2 Et2O), 810375 (for 11b), 810376
(for 12·2(Et2O)), and 810377 (for 13) contain the supplementary
crystallographic data for this paper and are available in the ESI.†
19 J. J. R. Frausto da Silva, R. J. P. Williams, The Biological Chemistry of
the Elements, Clarendon Press, Oxford, U.K., 1991.
20 C. Mealli, S. S. M. C. Godinho and M. J. Calhorda, Organometallics,
2001, 20, 1734–1742 and references therein.
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2009, 131, 11249–11255; (b) J. S. Thompson, A. Z. Bradley, K.-H. Park,
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2003, 22, 4426–4432; (d) G. Gro¨ger and U. Behrens, Organometallics,
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Chem., 2006, 45, 5742–5751.
Computational details
Calculations were performed using the GAUSSIAN 03 software
package,30 and the PBE functional31 without symmetry
constraints. The optimized geometries were obtained with
the Stuttgart/Dresden ECP (SDD) basis set32 to describe the
electrons of the copper atom. For all other atoms the 6–31g**
basis set was employed.33 Frequency calculations were performed
to confirm the nature of the stationary points. NMR chemical
shift calculations were obtained from single point calculations
using the optimized structures of 14a and 14b (BPE functional)
with the GIAO method at the B3LYP/6-31++G** level. SiMe4,
calculated at the same level of theory, was used as reference to
scale the absolute shielding value.
25 D. D. Perrin, W. L. F. Armarego, Purification of Laboratory Chemicals,
3rd ed., Pergamon, New York, 1988.
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(b) M. M. Diaz-Requejo, T. R. Belderrain, S. Trofimenko and P. J. Perez,
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7020 | Dalton Trans., 2011, 40, 7008–7021
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