4692 Organometallics, Vol. 17, No. 21, 1998
Steenwinkel et al.
0 °C. The reaction mixture was allowed to warm to RT and
then stirred for 24 h at this temperature. The reaction mixture
was then evaporated in vacuo to dryness. The brown-yellow
solid residue was washed with pentane (2 × 50 mL) and
extracted with benzene (4 × 50 mL). The combined benzene
extracts were evaporated in vacuo yielding a red-brown
powder, identified as 2, which was deemed to be of sufficient
purity for further use (yield: 1.83 g; 84%). Analytically pure
orange crystals of 2 (mp 128-129 °C, dec), which were suitable
for X-ray analysis, were obtained by slow diffusion of pentane
into a concentrated solution of 2 in THF. Anal. Calcd for
[C22H33ClN2Ru] (MW ) 462.07): C, 57.19; H, 7.20; N, 6.06.
Found: C, 57.14; H, 7.12; N, 6.15.
Syn t h esis of [R u (η5-Cp ){C6H 3(CH2NMe2)2-2,6-C,N}-
(P P h 3)] (5). A solution of freshly prepared [Na(Cp)]n (0.29 g,
3.29 mmol) in THF (4 mL) was added dropwise over a period
of 2 min to a dark blue solution of 43a (1.34 g, 2.27 mmol) in
THF (25 mL) at -78 °C. The reaction mixture was then
allowed to warm to RT over a period of 1 h and stirred for 14
h, during which time the color of the reaction mixture changed
from blue to yellow. The yellow suspension that had formed
was quenched with CH2Cl2 (5 mL), and all volatiles were
evaporated in vacuo to leave behind a dark yellow residue.
The crude product was extracted with benzene (2 × 50 mL).
The combined benzene extracts were concentrated to ca. 10
mL and layered with pentane, yielding 5 as a yellow solid
(yield: 1.05 g; 75%). Analytically pure orange crystals were
obtained by cooling a pentane/benzene (19:1, v/v) solution to
-25 °C, mp 141-143 °C (dec). Anal. Calcd for [C35H39N2PRu
+ 2/3 C6H6] (MW ) 671.86): C, 69.72; H, 6.45; N, 4.17.
Found: C, 69.89; H, 6.47; N, 3.95.
°C, then allowed to warm to RT over a period of 30 min, and
then stirred at this temperature for an additional 30 min. The
white precipitate that had formed, the aryldilithium reagent
8, was collected by centrifugation, washed with Et2O (50 mL),
and suspended in THF (20 mL). To this suspension was added
a suspension of [RuCl2(η6-C10H14)]2 (0.61 g, 2 mmol of Ru) in
THF (20 mL) at RT through a knee-tube. This mixture was
stirred at RT until all the solids had dissolved (1 h) and then
left undisturbed for 18 h, after which a dark red-brown solid
had precipitated. The solid was filtered off, washed with Et2O
(20 mL), and extracted with CH2Cl2 (2 × 50 mL). Evaporation
of the combined CH2Cl2 extracts to dryness afforded 9 as an
orange-brown solid, which was recrystallized from CH2Cl2 by
slow addition of Et2O. Yield: 0.32 g (38%) of orange-brown
crystals, mp 146-149 °C (dec). A reproducible combustion
analysis could not be obtained for this material.
Syn th esis of C6D3Br -Me2-2,6. A modification of a de-
scribed procedure was used.29 A vigorously stirred mixture
of bromo-2,6-xylene (14.9 g, 80.5 mmol), D2O (3 mL, 167 mmol),
and D2SO4 (11 mL, 200 mmol) was heated at reflux for three
1 min intervals and subsequently stirred for 15 h at RT. The
gray suspension that had formed was diluted with a saturated
aqueous solution of NaCl (25 mL), and this mixture was
extracted with CH2Cl2 (4 × 50 mL). The combined CH2Cl2
extracts where dried with MgSO4 and filtered, and the filtrate
was concentrated in vacuo to leave a colorless oil. This
procedure was repeated five times, until a deuterium enrich-
1
ment of the aryl group of ca. 99% (as determined by H NMR
integration) was obtained. After purification by flash distil-
lation the product was obtained as a colorless oil (10.8 g, 71%).
1H NMR (200 MHz, CDCl3): δ ) 2.45 (s, CH3).
Syn th esis of C6D3Br (CH2Br )2-2,6.10 A mixture of C6D3-
Br-Me2-2,6 (10.8 g, 57.7 mmol), NBS (22.6 g, 127 mmol), and
AIBN (1.0 g, 6 mmol) in methyl acetate (200 mL) was heated
at reflux temperature under illumination (100 W bulb) for 15
h. The solvent was then removed in vacuo, and the orange
oily residue was extracted with boiling hexane (4 × 100 mL).
The product crystallized from the combined hexane extracts
on cooling to -25 °C. Yield: 10.8 g (55%) of a white solid (mp
85-88 °C, dec). 1H NMR (200 MHz, CDCl3): δ ) 4.65 (s, CH2-
Br).3b
Rea r r a n gem en t of 2 to [Ru Cl{C6H3(CH2NMe2)2-2,4-
C,N}(η6-C10H14)] (3). A yellow solution of 2 (100 mg, 0.22
mmol) in C6H6 (50 mL) was heated at reflux for 3 h, while the
color changed from yellow to orange-yellow. Following this
procedure, all volatiles were removed in vacuo, leaving a brown
powder. This residue was washed with Et2O (2 × 25 mL) and
then dried in vacuo. Yield: 74 mg (74%) of 3 as a red-brown
powder. Analytically pure orange crystals of 3 (mp 132-136
°C, dec), which were suitable for an X-ray analysis, were
obtained by slow evaporation (in air) of a solution of 3 in a
mixture of CH2Cl2 and MeOH (1:5 v/v). Anal. Calcd for
[C22H33ClN2Ru + 1/4 CH2Cl2] (MW ) 483.31): C, 55.30; H,
6.99; N, 5.80. Found: C, 55.45; H, 6.98; N, 5.56.
In d ep en d en t Syn th esis of 3. Solid NaPF6 (0.30 g, 1.4
mmol) was added to a solution of 1,3-bis[(dimethylamino)-
methyl]benzene (0.27 g, 1.4 mmol) and [RuCl2(η6-C10H14)]2
(0.43 g, 0.7 mmol) in CH2Cl2 (10 mL), and this mixture was
stirred at RT for 18 h. After filtration, the solution was
separated by column chromatography using silica and CH2-
Cl2 as eluent. A yellow band, which eluted slowly, was
collected and concentrated to ca. 5 mL. Then MeOH (2 mL)
was added, and the solution was slowly evaporated in air.
Analytically pure orange crystals of 3 were collected from the
dark brown solution by filtration and were then dried in vacuo.
Yield: 0.17 g (27%).
Rea r r a n gem en t of 5 to [Ru (η5-Cp ){C6H3(CH2NMe2)2-
2,4-C,N}(P P h 3)] (6). A yellow solution of 5 (0.18 g, 0.29 mmol)
in C6H6 (100 mL) was heated at reflux temperature for 2.5 h;
no color change was observed. The solvent was removed in
vacuo, leaving a yellow solid, identified as 6. Analytically pure
orange crystals of 6 (mp 150-152 °C, dec), which were suitable
for an X-ray analysis, were obtained by cooling a pentane/
benzene (19:1, v/v) solution to -25 °C. Anal. Calcd for
[C35H39N2PRu + 1/3 C6H6] (MW ) 645.82): C, 68.81; H, 6.40;
N, 4.34. Found: C, 68.88; H, 6.40; N, 4.02.
Syn t h esis of [1,4-{R u Cl(η6-C10H 14)}2{C6(CH 2NMe2)4-
2,3,5,6-C,N-C′,N′}] (9). A solution of n-BuLi (1.5 mL, 1.6 M
in hexanes, 2.4 mmol) was added dropwise over a period of 2
min to a suspension of 7 (0.51 g, 1.1 mmol) in Et2O (20 mL) at
-78 °C. The reaction mixture was stirred for 15 min at -78
Syn th esis of C6D3Br (CH2NMe2)2-2,6. Neat HNMe2 (18
mL, 0.27 mol) was added to a stirred solution of C6D3Br(CH2-
Br)2-2,6 (10.8 g, 32 mmol) in Et2O (200 mL) at 0 °C. The
reaction mixture was stirred at this temperature for 2 h. The
mixture was then allowed to warm to RT and stirred for an
additional 14 h. All volatiles were evaporated in vacuo, and
then an aqueous solution of NaOH (100 mL, 2.5 M) was added
to the remaining white, solid residue. The mixture was
extracted with hexane (2 × 100 mL), the combined hexane
fractions were dried with MgSO4 and filtered, and the filtrate
was concentrated in vacuo. After flash distillation of the pale
yellow oily residue the product was obtained as a colorless oil,
which slowly solidified upon standing at -25 °C. Yield: 7.4 g
(84%). 1H NMR (200 MHz, CDCl3): δ ) 3.50 (s, 4 H, CH2N),
2.26 (s, 12 H, N CH3). 2H NMR (31 MHz, C6H6): δ ) 7.3 (s, 2
D, ArD), 6.9 (s, 1 D, ArD). 13C{1H} NMR (50 MHz, CDCl3): δ
) 138.6 (s, Cortho), 129.0 (t, 1J DC ) 25 Hz, Cmeta), 126.7 (s, CBr),
1
126.1 (t, J
) 25 Hz, Cpara), 63.9 (s, CH2N), 45.6 (s, NCH3).
DC
Syn th esis of [Ru Cl{C6D3(CH2NMe2)2-2,6-C,N}(η6-C10H14)]
(2-d 3). This complex was prepared using the method described
for the preparation of complex 2, but now starting from [Li-
{C6D3(CH2NMe2)2-2,6}]2, 1-d3, which was prepared in situ in
Et2O from C6D3Br(CH2NMe2)2-2,6 and 2 equiv of t-BuLi at -78
°C.
Syn th esis of [Ru Cl{C6D3(CH2NMe2)2-2,6-N,C,N′}(P P h 3)]
(4-d 3). This complex was prepared using the method described
for the synthesis of 4,3a but now starting from [Li{C6D3(CH2-
(29) van der Zeijden, A. A. H.; van Koten, G.; Luijk, R.; Nordemann,
R. A.; Spek, A. L. Organometallics 1988, 7, 1549.
Steenwinkel, Pablo
