H. Huang et al. / Polyhedron 27 (2008) 734–738
735
investigation on the synthesis, characterization, and the
crystal structure analysis of two half sandwich ruthenium
complexes with the ‘‘Ph2nacnac’’ ligand.
5.46. Found: C, 65.82; H, 6.81; N, 5.46%. 1H NMR
(CD2Cl2, 300 MHz, 25 ꢁC) d 1.23 (1;H, s, C5(CH3)5); 1.72
(6H, s, CH3); 4.50 (1H, s, HC); 6.97 (2H, t, 3JHH = 7.5 Hz,
3
p-H-Ph); 7.05 (4H, d, JHH = 8.7 Hz, o-H-Ph); 7.26 (4H, t,
2. Experimental
3JHH = 7.5 Hz, m-H-Ph). IR (hexane, cmꢀ1): tCO 1910 (vs).
2.1. General
2.1.3. X-ray crystallography
Crystal data and other parameters for complexes 4 and 5
are given in Table 1. Intensity data were collected at
213(2) K, on Bruker Smart CCD diffractometers
using graphite-monochromated Mo Ka radiation (k =
Air-sensitive reactions were performed in oven-dried
glassware, using standard SCHLENK techniques, under an
atmosphere of nitrogen, which was deoxygenated over
BASF catalyst and dried over Aquasorb, or in a Braun dry-
box. Methylene chloride and hexane were dried over an
alumina column under nitrogen [19]. Methanol was dis-
˚
0.71073 A). Of the 17,362 and 7558 reflections that were
collected, 5488 (Rint = 0.0413) and 4186 (Rint = 0.0249)
were unique for complexes 4 and 5, respectively. Empirical
absorption corrections were employed. The structures were
solved by direct methods. The final refinement was done by
full-matrix least squares based on F2 with anisotropic
thermal parameters for all non-hydrogen atoms, and the
hydrogen atoms were generated geometrically.
˚
tilled from Linde type 4 A molecular sieves. NMR spectra
were recorded on a Varian Unity Plus 300 or 500 FT spec-
1
trometer. H NMR spectra were referenced to the protio
impurity in the solvent: C6D6 d (7.16 ppm), CD2Cl2
d
(5.32 ppm). Coupling constants are reported as absolute
values in units of Hertz. IR spectra were recorded on a Per-
kin–Elmer FTIR 1600 Series spectrophotometer. Elemen-
tal analyses were performed by Schwartzkopf (Woodside,
NY).
RuCl3 Æ 3H2O (Johnson Matthey Ltd.) and pentamethyl-
cyclopentadiene (Cp*H) (Acros) were used without further
purification. [Cp*RuCl2]2 [20] and Ph2nacnac [21] were pre-
pared according to published methods.
3. Results and discussion
Complex 4 was obtained via two steps in a one pot reac-
tion with an overall yield of 81%. [Cp*RuCl2]2 was stirred
with K2CO3 in MeOH to give [Cp*Ru(OMe)]2, which
reacted with the Ph2nacnac ligand to give 4 as a red air-sen-
sitive solid. Reaction of 4 with CO in hexane afforded 5 as a
yellow solid in high yield as shown in Scheme 1. This
yellow complex is moderately stable in air, unlike its acac
analogue [11]. The CO stretching frequency in the IR of
5 is at 1910 cmꢀ1 in hexane, while tꢀh1at for the acac ana-
logue Cp*Ru(acac)(CO) is 1915 cm (KBr) [11]. There
2.1.1. Synthesis of Cp*Ru(Ph2nacnac) (4)
[Cp*RuCl2]2 (50 mg, 0.17 mmol) and dry K2CO3
(150 mg, 1.15 mmol) were suspended in dry N2 saturated
MeOH (10 mL) and allowed to stir for 6 h to give an inten-
sely red solution with some solid. Ph2nacnac (41 mg,
0.17 mmol) was added to the solution, which was allowed
to react for a half hour to give a red solution. The solvent
was removed in vacuo to give a dark red solid, which was
extracted with hexane (50 mL) and filtered. The solvent
was removed from the filtrate to give the product as a dark
red solid; 50 mg, 81%. Recrystallization by slow evapora-
tion from hexane gave dark red crystals suitable for X-
ray diffraction. Anal. Calc. for C27H32N2Ru: C, 66.77; H,
6.64; N, 5.77. Found: C, 66.39; H, 6.94; N, 5.78%. 1H
NMR (C6D6, 300 MHz, 25 ꢁC) d 1.08 (15H, s, C5(CH3)5);
1.90 (6H, s, CH3); 5.39 (1H, s, HC); 7.00–7.26 (10H, m,
H-Ph).
Table 1
Crystal data for complexes 4 and 5
4
5
Formula
C
485.62
P2ð1Þ=n
9.363(6)
23.983(15)
11.137(7)
27H32N2Ru
C28H32N2ORu
513.63
Formula weight
Space group
ꢀ
P1
˚
a (A)
7.2099(19)
11.924(3)
14.596(4)
79.706(4)
75.865
81.585
1190.4(5)
2
˚
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
110.285(10)
3
˚
V (A )
2346(3)
4
1.375
0.684
213(2)
Z
2.1.2. Synthesis of Cp*Ru(Ph2nacnac)(CO) (5)
Dcalc (g cmꢀ3
)
1.433
0.681
213(2)
Cp*Ru(Ph2nacnac) (23 mg, 0.047 mmol) was dissolved
in hexane (10 mL) to give a red solution. CO (1.0 mL,
0.047 mmol) was added by syringe. The color lightened.
CO (3 mL/time · 17 times) was added by syringe and the
solution was allowed to react overnight to give a brown
yellow solution. The solvent was removed in vacuo to give
the adduct as yellow solid, with a little brown red tint;
24 mg, 99%. Recrystallization by slow evaporation from
hexane gave yellow crystals suitable for X-ray diffraction.
Anal. Calc. For C28H32N2ORu: C, 65.47; H, 6.28; N,
l [Mo Ka] (mmꢀ1
Temp. (K)
)
Diffractometer
Radiation
bruker smart apex CCD bruker smart apex CCD
˚
˚
Mo Ka (0.71073 A)
Mo Ka (0.71073 A)
Crystal size (mm)
F(000)
0.30 · 0.20 · 0.10
1008
0.40 · 0.15 · 0.08
532
Measured reflections 17362
7558
4186
Independent
reflections
R (F), %
5488
0.0446
0.0991
0.0292
0.0769
R (wF2), %
Huang, Hui
