Inorganic Chemistry
1
In the H NMR spectra of the Ru(II) complexes Ru2−Ru5,
a splitting of the signals belonging to the benzylic protons is
present. Furthermore, for complexes Ru2 and Ru4, also a
splitting of the signals belonging to the isopropylic methyl
1
the neighboring donor atoms, which could be formed by the
coordination of both additional donor atoms to the Ru(II)
center. The subsequent crystal structure analysis of Ru3 (OPh)
showed that the diastereotopic environment is created by the
coordination behavior of the ligand L3. L3 coordinates in a
defined way, where the additional donor atoms point away
from the ruthenium center.
Figure 3. Solid-state structures (ORTEP representation) of the
heteroleptic Cu(I) complexes Cu2 (left) and Cu4 (right). Ellipsoids
are drawn at 50% probability. Hydrogen atoms, PF6 counteranions,
Single crystals suitable for X-ray analysis could be obtained
for 8 of the 13 novel complexes (see Tables 1 and 2) by
−
and solvent molecules are omitted for clarity.
Table 2. Selected Crystallographic Bond Lengths (pm) and
Angles (deg) of the Ru(II) Complexes Ru1 and Ru3
a
copper center, differs clearly from the 90° of an ideal
tetrahedron (see Table 1). However, because of the additional
bulkiness of the OR and SR substituents at the 2 and 9
positions, Cu2 and Cu4 appear less distorted than the
reference complex Cu1 with methyl groups only. A
comparison of further structural parameters of Cu2, Cu4,
and Cu1 (see Table 1) does not show major differences with
respect to the basic coordination geometry (e.g., N1−Cu−N2
Ru1 (space group
Ru3 (space
Ru3 (space
b
b
a
b
P2 /c)
group P1
̅
)
̅
group P1)
1
Ru−N1
Ru−N2
Ru−N3
Ru−N4
Ru−N5
Ru−N6
Ru−X1
Ru−X2
210.4(5)
210.0(4)
206.8(5)
206.3(5)
203.8(4)
205.9(5)
206(1)
213(1)
214(1)
203(1)
207(1)
204(1)
208.0(9)
483(1)
490(1)
214.6(9)
204(1)
206(1)
207(1)
212.0(9)
485(1)
486(1)
=
80.53(13)° for Cu1 and 80.97(15)° for Cu2; Cu−N1 =
2
08.4(3) pm for Cu1 and 208.4(4) pm for Cu2). This
indicates a small impact of the substituents at 1,10-
phenanthroline on the general structure around the Cu(I)
center. Most importantly, in the solid-state structures of the
N1−Ru−N2
N3−Ru−N4
N5−Ru−N6
N1−Ru−N3
N1−Ru−N4
N1−Ru−N5
N1−Ru−N6
N2−Ru−N3
N2−Ru−N4
N2−Ru−N5
N2−Ru−N6
79.4(2)
171.3(2)
79.3(2)
92.9(2)
93.2(2)
101.4(2)
171.5(2)
88.3(2)
98.8(2)
177.3(2)
100.3(2)
80.1(4)
79.0(5)
78.6(5)
95.2(4)
173.4(5)
87.3(5)
102.1(5)
88.9(4)
102.5(5)
94.5(5)
172.6(5)
78.9(5)
78.2(4)
78.0(5)
97.4(5)
175.4(5)
88.6(5)
102.5(5)
92.4(5)
102.4(5)
93.1(5)
170.9(5)
i
i
heteroleptic Cu(I) complexes Cu2 (O Pr) and Cu4 (S Pr), the
additional donor functions point away from the copper center
(
see Figure 3), resulting in Cu−X distances of ≥4.5 Å. This
clearly shows that there is no interaction between the Cu(I)
center and additional donor atoms in the heteroleptic
complexes. Consequently, no change in the P NMR chemical
shift was observed when the additional donor functions were
introduced.
3
1
Crystal Structure Analysis of the Homoleptic Copper
Complexes Cu2′−Cu5′. All homoleptic Cu(I) complexes
Cu2′−Cu5′ could be examined by X-ray crystallography (see
Figure 4), and they show again the typical distorted tetrahedral
a
The values in parentheses represent the experimental estimated
b
standard deviation of the measurement. Ru3 crystallized in a lattice
with two twinned units of the respective complex. The two units are
referred as Ru3 and Ru3 .
2
,22,49
structure.
In addition, the reference complex Cu1′
a
b
exhibits the smallest angle between the two ligand planes
(
79.4°) compared to the substituted derivatives Cu2′−Cu5′
layering a dichloromethane solution of the respective complex
with ethanol and n-hexane. As a result, structural data were
received for the heteroleptic Cu(I) complexes Cu2 and Cu4,
the homoleptic Cu(I) complexes Cu2′−Cu5′, and the Ru(II)
complexes Ru1 and Ru3 and are discussed below. Interest-
ingly, almost all Cu(I) compounds crystallize in a triclinic
crystal system with the space group P1 (see Table 1).
̅
Crystal Structure Analysis of the Heteroleptic Copper
Complexes. Both Cu(I) complexes Cu2 and Cu4 (see Figure
(82.3−88.7°; see Table 1). Hence, Cu1′ features the largest
distortion from the tetrahedral coordination sphere, whereas
the additional substituents in Cu2′−Cu5′ reduce the extent of
i
the flattening. The different types of substituents (O Pr, OPh,
i
S Pr, and SPh) have almost no influence on the Cu−N
distances (e.g., Cu−N1 = 203.6(3) pm for Cu3′, 205.3(3) pm
for Cu4′, and 204(1) pm for Cu5′) and the bite or tetrahedral
angles, which are in the same range for all complexes (see
Table 1). Special attention was then paid to the Cu−X
i
i
3
) possess a distorted tetrahedral ground-state structure, which
distances (XO Pr, OPh, S Pr, or SPh). As a main difference
to the heteroleptic Cu(I) complexes, all homoleptic com-
pounds Cu2′−Cu5′ possess one Cu−X distance, which is
significantly shortened. For instance, in Cu3′, the Cu−O1
distance is 328.9(2) pm, whereas Cu−O3 is 457.3(2) pm. This
indicates a weak interaction between the copper center and
one of the additional donor atoms. It should be noted that the
crystal structure of complex Cu2′ has a higher symmetry than
24,30,45
is commonly observed for this class of compounds.
This
is mainly caused by the bulky and rigid xantphos ligand and the
large difference in the bite angles of the diimine and
diphosphine [e.g., for Cu2, N1−Cu−N2 = 80.97(15)° and
P1−Cu−P2 = 120.43(5)°]. With 76.9° (Cu1), 85.9° (Cu2),
and 87.8° (Cu4), the angle between the two ligand planes,
which are spanned through the chelating heteroatoms and
D
Inorg. Chem. XXXX, XXX, XXX−XXX