sp3 C-H/D2 Exchange Reaction by a Ru(II) Complex
Organometallics, Vol. 24, No. 20, 2005 4807
and vacuum line techniques, unless noted otherwise. Benzene,
toluene, THF, and hexane were distilled over sodium/benzo-
phenone ketyl, and these solvents were stored under nitrogen.
Pentane was distilled over potassium/benzophenone ketyl and
was stored under vacuum. PMe3 was prepared from P(OPh)3
with MeMgI. Ru(η4-1,5-COD)(η6-1,3,5-COT) (1) was prepared
according to literature procedures with magnetic stirring
instead of ultrasonic irradiation.36 cis-RuH2(PMe3)4 (5),37 cis-
RuMe2(PMe3)4 (6),38 cis-RuClMe(PMe3)4 (7),22a and cis-Ru-
[OC6H4(2-CH2)(6-Me)-κ2O,C](PMe3)4 (8)9b were prepared by the
literature methods. Potassium 2,6-dimethylbenzenethiolate
was prepared by the reaction of 2,6-dimethylbenzenethiol with
KOH in methanol. Benzene-d6 was distilled over sodium wires
and was stored under vacuum. D2 gas was purchased from
Nippon Sanso and used as received. All other reagents were
obtained from commercial suppliers and used as received.
Reactions in a NMR tube under vacuum or hydrogen were
carried out by use of a 5 mm φ Aldrich NMR tube with a Teflon
valve, in which benzene-d6 was introduced by valve-to-valve
distillation and H2 or D2 gas was introduced by use of mercury
manometer. 1H NMR spectra were recorded on a JEOL LA
zenethiol (120 µL, 0.901 mmol) were added into the solution.
The solution was stirred at 70 °C for 200 h. The reaction
mixture was then evaporated to dryness, and the resulting
white powder was extracted with dry hexane (30 mL). The
extract was separated by cannula and was concentrated, and
was then kept at -20 °C for a night to give white platelike
crystals of 3 in 20% yield (79.6 mg, 0.146 mmol). 1H NMR
(300.4 MHz, C6D6): δ 0.99 (d, J ) 6.6 Hz, 9H, PMe3), 1.10 (vt,
J ) 2.7 Hz, 18H, mutually trans-PMe3), 1.11 (d, J ) 5.4 Hz,
9H, PMe3), 2.70 (tdd, J ) 13.7, 5.3, 3.7 Hz, 2H, ortho-CH2),
2.88 (s, 3H, ortho-SC6H3Me), 7.06 (d, J ) 4.5 Hz, 2H, meta-
SC6H3), 7.48 (t, J ) 4.5 Hz, 1H, para-SC6H3). 31P{1H} NMR
(121.6 MHz, C6D6): δ -16.8 (td, J ) 27, 18 Hz, 1P, PMe3 trans
to -CH2-), -8.4 (t, J ) 27 Hz, 2P, mutually trans-PMe3), 0.0
(td, J ) 27, 18 Hz, 1P, PMe3 trans to -S-). Anal. Found: C,
44.06; H, 8.56; S, 6.02. Calcd for C20H44SP4Ru: C, 44.35; H,
8.19; S, 5.92.
Reaction of Ru(1-5-η5-cyclooctadienyl)(SC6H3Me2-2,6)-
(PMe3)2 (2) with PMe3. Complex 2 (7.8 mg, 0.016 mmol), a
flame shield capillary with PPh3 and CH2Cl2 as internal
standard, benzene-d6 (510 mL), and PMe3 (15.9 mL, 0.156
mmol) were placed in an NMR tube. Heating at 70 °C for 222
h gave thiaruthenacycle complex 3 in 91% yield.
1
300 spectrometer (300.4 MHz for H). Chemical shifts (δ) are
given in ppm, relative to internal TMS for 1H and external
85% H2PO3 in deuterated water for 31P. All coupling constants
are given in Hz. The deuterium content in the ortho-methyl
and mercapto groups was estimated on the basis of the relative
intensity of 1,4-dioxane as an internal standard. Since the
relative signal intensity was found to depend on the pulse
delay, the pulse delay was set to 120 s for complete relaxation.
Elemental analyses were carried out by a Perkin-Elmer 2400
series II CHNS analyzer. GLC analysis was performed on a
Shimazu GC-8A with a FID detector using a Porapak Q
column.
Reaction of cis-Ru[SC6H3(2-CH2)(6-Me)-K2S,C](PMe3)4
(3) with Hydrogen. Complex 3 (9.9 mg, 0.018 mmol) and
triphenylmethane (10.3 mg, 0.0422 mmol) as an internal
standard were placed into an Aldrich NMR tube with PTFE
screw cap under Ar. The NMR tube was evacuated; then
benzene-d6 was introduced (600 µL). Hydrogen gas (0.1 MPa)
was charged into the NMR tube, and the reaction was
monitored by NMR. After exposure of 3 to an atmosphere of
hydrogen for 10 min, (hydrido)(thiolato)ruthenium(II) complex
4 was detected in 90% yield. Since complex 4 can survive only
under hydrogen atmosphere, it was characterized spectrosp-
copically. 4: 1H NMR (300.4 MHz, C6D6): δ -8.63 (ddt, J )
39.6, 13.2, 9.6 Hz, 1H, Ru-H), 1.05 (d, J ) 7.2 Hz, 9 H, apical
PMe3), 1.25 (vt, J ) 3.0 Hz, 18 H, mutually trans PMe3), 1.26
(d, J ) 4.5 Hz, 9 H, PMe3), 3.01 (s, 6H, ortho-SC6H3Me2), 7.05
(t, J ) 7.5 Hz, 1H, para-SC6H3Me2), 7.20 (d, J ) 7.5 Hz, 2H,
meta-SC6H3Me2). 31P{1H} NMR (122.6 MHz, C6D6): δ -17.8
(td, J ) 27, 16 Hz, 1P, PMe3 trans to H), -5.9 (dd, J ) 32, 27
Hz, 2P, mutually trans PMe3), 6.6 (td, J ) 26, 17 Hz, 1P, PMe3
trans to S).
Reaction of 1/PMe3 with 2,6-Dimethylbenzenethiol
Giving Ru(1-5-η5-cyclooctadienyl)(SC6H3Me2-2,6)(PMe3)2
(2). Although this compound can be prepared at room tem-
perature in benzene, the following procedure gave the highest
yield. Complex 1 (549.5 mg, 1.742 mmol) was placed into a 25
mL Schlenk tube, where benzene (ca. 3 mL) was introduced
by valve-to-valve distillation. PMe3 (450 µL, 3.04 mmol) was
added to the solution by a hypodermic microsyringe. The
reaction system was stirred at 50 °C for 17 h, and then 2,6-
dimethylbenzenethiol (140 µL, 1.05 mmol) was added into the
reaction mixture. The reaction mixture was stirred at 50 °C
for an additional 100 h. All volatile materials were removed
under reduced pressure, and the resulting orange oil was
washed with dry hexane (100 mL) to give an analytically pure
yellow powder of 2 in 59% yield (294.9 mg, 1.02 mmol). 1H
NMR (300.4 MHz, C6D6): δ 0.33 (qt, J ) 11.6, 2.7 Hz, 1H,
exo-7-CH2), 0.91 (d, J ) 7 Hz, 9H, PMe3), 1.05 (m, 1H, endo-
7-CH2), 1.26 (m, 2H, endo-6- and -8-CH2), 1.51 (d, J ) 8.1
Hz, 9H, PMe3), 1.85 (m, exo-6- and -8-CH2), 2.15 (br, 1H, 1-
or 5-CH), 2.24 (br, 1H, 5- or 1-CH), 2.62 (s, 6H, SC6H3Me2-
2,6), 3.21 (m, 1H, 2- or 4-CH), 3.31 (m, 1H, 4- or 2-CH), 5.67
(br. td, 1H, 3-CH), 7.07 (t, J ) 7 Hz, 1H, para-SC6H3), 7.20 (d,
J ) 7 Hz, 2H, meta-SC6H3). 31P{1H} NMR (121.6 MHz, C6D6):
δ -7.5 (d, J ) 32 Hz, 1P, PMe3), -5.3 (d, J ) 32 Hz, 1P, PMe3).
Anal. Found: C, 53.12; H, 7.97; S, 6.77. Calcd for C22H38P2-
RuS: C, 53.10; H, 7.70; 6.44.
The reaction of 3 with D2 is carried out in the similar
manner by using a manometer: 3 (10.3 mg, 0.019 mmol),
CHPh3 (10.7 mg, 0.0438 mmol), benzene-d6 (0.6 mL), D2 (4.75
mL, 0.199 mmol).
Evacuation of cis-RuH(C6H3Me2-2,6)(PMe3)4 (4) in Ben-
zene-d6. A typical experiment was carried out as follows.
Complex 3 (9.5 mg, 0.018 mmol) and triphenylmethane (9.3
mg, 0.017 mmol) were placed in an Aldrich NMR tube with
PTFE screw cap under Ar. Benzene-d6 was introduced into
the NMR tube by valve-to-valve distillation, and the system
was exposed to H2 (0.1 MPa) for a night at room temperature.
Complete formation of 4 was checked by NMR, and then the
reaction system was evacuated by freeze-pump-thaw cycles.
The NMR study indicates formation of 3 in 40% yield after 24
h at room temperature. Introduction of ethylene (0.1 MPa) into
the solution of 4 significantly encourages formation of 3 (95%
yield) within 7 h at room temperature.
Reaction of 1/PMe3 with 2,6-Dimethylbenzenethiol
Giving cis-Ru[SC6H3(2-CH2)(6-Me)-K2S,C](PMe3)4 (3). Com-
pound 1 (234.3 mg, 0.743 mmol) was placed in a 25 mL Schlenk
tube in which benzene (4 mL) was induced via valve-to-valve
distillation. PMe3 (370 µL, 2.86 mmol) and 2,6-dimethylben-
Reaction of cis-Ru[SC6H3(2-CH2)(6-Me)-K2S,C](PMe3)4
(3) with Hydrogen in the Presence of PMe3. As described
above, complex 3 (9.1 mg, 0.017 mmol), triphenylmethane (10.0
mg, 0.0409 mmol), and benzene-d6 were placed into an NMR
tube, and then dry N2 gas was introduced into the NMR tube.
PMe3 (2.0 µL, 0.19 mmol) was added into the NMR tube, and
the NMR spectrum was measured. Then the NMR tube was
frozen by liquid N2 and evacuated to introduce H2 gas.
Reaction of cis-Ru[OC6H3(2-CH2)(6-Me)-K2O,C](PMe3)4
(8) with Hydrogen. Complex 8 (10.5 mg, 0.0200 mmol) was
placed in an NMR tube into which benzene-d6 (0.6 mL) was
(36) Itoh, K.; Nagashima, H.; Ohshima, T.; Oshima, N.; Nishiyama,
H. J. Organomet. Chem. 1984, 272, 179.
(37) Jones, R. A.; Wilkinson, G.; Colquohoun, I. J.; McFarlane, W.;
Glass, A. M. R.; Hurshouse, M. B. J. Chem. Soc., Dalton Trans. 1980,
2480.
(38) Andersen, R. A.; Jones, R. A.; Wilkinson, G. J. Chem. Soc.,
Dalton Trans. 1978, 446.
Hirano, Masafumi
