C.A. Madrigal et al. / Journal of Organometallic Chemistry 693 (2008) 2535–2540
2539
2
such conditions, the indenyl complex 4 is among the most efficient
half-sandwich ruthenium(II) catalysts reported to date.
NMR (CD2Cl2, 273 K, d) 43.6 (t, PPh2 JPP = 28 Hz), ꢀ54.8 (dd, PTA,
2JPP = 319, 28 Hz), ꢀ72.7 (dd, PTA, JPP = 319, 28 Hz) ppm. 1H NMR
2
(CD2Cl2, 293 K, d) 8.00–6.33 (m, 10H, Ph), 5.12 (AB spin system, 3H,
PTA, JHAHB = 12 Hz), 4.92 (AB spin system, 3H, PTA, JHAHB = 12 Hz),
4.83–4.36 (m, 18H, C5H3, OCH2, CHN and PTA), 4.18 (s, 5H, C5H5), 3.83
4. Experimental
(AB spin system, 3H, PTA, JHAHB = 16 Hz), 3.69 (AB spin system, 3H,
3
4.1. General procedures
PTA, JHAHB = 16 Hz), 2.36 (m, 1H, CH(CH3)2), 1.08 (d, 3H, CH3, JHH
=
7 Hz), 0.92 (d, 3H, CH3, 3JHH = 7 Hz) ppm. 13C{1H} NMR (CD2Cl2, 293 K,
d) 169.5 (COCH2), 146.1–127.4 (Ph), 86.8 (d, CPPh2, JCP = 37 Hz), 75.9
(C5H3), 73.5 (C5H3), 72.9 (m, CCPPh2), 72.7 (br, 6C, NCH2N), 71.9
(C5H5), 71.0 (C5H3), 69.8 (CHN), 67.3 (OCH2), 50.6 (br, 3C, NCH2P),
49.8 (br, 3C, NCH2P), 27.3 (CH(CH3)2), 19.7 (CH3), 14.9 (CH3) ppm. Anal.
Calc. for [RuCl2(PTA)2(FcPN)] ꢃ 1.5CH2Cl2: C, 45.52; H, 5.06; N, 8.95.
Found: C, 45.01; H, 5.52; N, 9.27%.
All manipulations involving organoruthenium complexes were
performed under inert atmosphere on nitrogen, using standard
Schlenk techniques. Solvents were dried by standard methods and
distilled under nitrogen before use. The compounds fac-[RuCl2-
(PR3)2{j2(P,N)-FcPN}] (PR3 = PMe3 (1), PMe2Ph (2)) [8],
fac-[RuCl2(dppm){j2(P,N)-FcPN}] (3) [8], [Ru(g5-C9H7){j2(P,N)-
FcPN}(PPh3)][PF6] (4) [9], [RuCl(g5-C9H7){j2(P,N)-FcPN}] (5) [9]
and [RuX(g6-arene){j2(P,N)-FcPN}][PF6] (g6-arene = p-cymene,
X = Cl (6), H (7); g6-arene = 1,2,3,4-tetramethylbenzene, X = Cl (8))
[9] were prepared by previously reported methods. [RuCl2(PPh3)-
{j2(P,N)-FcPN}] [11] and PTA [17] phosphane were prepared accord-
ing to the literature procedure. All other chemicals were obtained
from Aldrich Chemical Co. and Acros Organics and used without fur-
ther purification. The C, H, and N analyses were carried out with a
Perkin–Elmer 240-B microanalyzer. NMR spectra were recorded
on a Bruker AC-400 instruments at 400.1 MHz (1H), 161.9 (31P) or
100.6 MHz (13C) using SiMe4 or 85% H3PO4 as standards. DEPT
experiments were carried out for all the compounds. Abbreviations
used: br, broad signal; d, doublet; dd, double doublet; m, multiplet;
sept, septuplet; s, singlet; t, triplet. Gas chromatographic measure-
ments were made on Hewlett–Packard HP6890 equipment using a
Supelco Beta-Dex 120 (30 m, 250 lm) column.
4.4. Synthesis of fac-[RuCl2(PTA)2{j2(P,N)-FcPN}] (10b)
A solution of mer–trans-[RuCl2(PTA)2{j2(P,N)-FcPN}] (100 mg,
0.1 mmol) in CH3OH (5 mL) was stirred at room temperature for
10 min. The solvent was then removed at reduced pressure and
the resulting solid extracted with dichloromethane. The resulting
solution was concentrated under vacuum to a volume of approx.
0.5 mL. Addition of hexane afforded an orange precipitate. The sol-
vents were decanted and the solid was washed with hexane
(2 ꢂ 10 mL) and dried under reduced pressure to afford complex
10b. Yield: 87 mg (85%). 31P{1H}-NMR (CD3OD, 293 K, d) 37.1 (dd,
PPh2 JPP = 34, 33 Hz), ꢀ30.8 (t, PTA, JPP = 2JPP = 33 Hz), ꢀ35.0 (t,
2
2
2
PTA, JPP = 2JPP = 34 Hz) ppm. 1H NMR (CD2Cl2, 293 K, d) 8.82–7.02
(m, 10H, Ph), 5.50 (s, 1H, C5H3), 4.91 (s, 1H, C5H3), 4.79–3.96 (m,
24H, C5H3, OCH2, CHN, PTA), 4.11 (s, 5H, C5H5), 3.76 (AB spin sys-
tem, 3H, JHAHB = 16 Hz, PTA), 3.31 (m, 1H, CH(CH3)2), 3.11 (AB spin
4.2. Synthesis of mer–trans-[RuCl2{P(OMe)3}2{j2(P,N)-FcPN}] (9)
3
system, 3H, JHAHB = 16 Hz, PTA), 1.10 (d, CH3, JHH = 4 Hz), 0.98 (d,
3
CH3, JHH = 4 Hz) ppm.13C{1H}-NMR (CD3OD, 293 K, d) 168.8
P(OMe)3 (28 lL, 0.24 mmol) was added to
a solution of
(COCH2), 146.4 - 127.7 (Ph), 78.1 (d, CPPh2, JCP = 40 Hz), 74.4
[RuCl2(PPh3){j2(P,N)-FcPN}] (0.100 g, 0.11 mmol) in dichlorometh-
ane (10 mL). The mixture was stirred for 1.5 h at room temperature
and then concentrated under vacuum to a volume of approx.
0.5 mL. Addition of hexane afforded a yellow precipitate. The sol-
vents were decanted and the solid was washed with hexane
(3 ꢂ 20 mL) and dried under reduced pressure to afford complex
9. Yield: 90 mg (85%). 31P{1H} NMR (CD2Cl2, 273 K, d) 5.6 (dd,
2
3
(C5H3), 74.3 (d, OCCCPPh2, JCP = 17 Hz), 74.0 (d, CHN, JCP = 4 Hz),
2
73.6 (C5H3), 72.8 (d, CCPPh2, JCP = 16 Hz), 72.3 (d, 3C, NCH2N,
3JCP = 5 Hz), 72.1 (C5H5), 71.5 (d, 3C, NCH2N, JCP = 6 Hz), 68.4
3
(OCH2), 54.5 (d, 3C, NCH2P, JCP = 17 Hz), 52.7 (d, 3C, NCH2P,
JCP = 16 Hz), 28.6 (CH(CH3)2), 18.3 (CH3), 15.1 (CH3) ppm. Anal. Calc.
for [RuCl2(PTA)2(FcPN)]: C, 49.65; H, 5.42; N, 10.13. Found: C,
49.21; H, 5.03; N, 9.78%.
2
2
PPh2, JPP = 47, 547 Hz), 117.8 (dd, P(OMe)3, JPP = 65, 547 Hz),
136.0 (dd, P(OMe)3, JPP = 47, 65 Hz) ppm. 1H NMR (CD2Cl2,
2
4.5. Transfer hydrogenation of ketones ? General procedure
293 K, d) 8.71 (m, 2H, Ph), 7.13–7.47 (m, 8H, Ph), 4.94 (m, 1H,
C5H3), 4.68 (m, 2H, C5H3), 4.40 (m, 1H, OCH2), 4.28 (m, 1H,
OCH2), 4.03 (br, 11 H C5H5 P(OCH3)3), 3.97 (br, 3H, P(OCH3)3),
The samples were typically prepared as follows: the ketone
(5 mmol), ruthenium catalyst precursor (0.01 mmol, 0.2 mol% of
Ru) and propan-2-ol (47 mL) were introduced into a Schlenk tube
fitted with a condenser and heated at 82 °C for 15 min in an inert
atmosphere. NaOH was then added (3 mL of a 0.08 M solution in
propan-2-ol, 4.8 mol%) and the reaction monitored by gas chroma-
tography. The corresponding alcohol and acetone were the only
products detected in all cases. The identity of the alcohol was as-
sessed by comparison with commercially available (Aldrich Chem-
ical Co. or Acros Organics) pure samples.
3
3.83 (t, 1H, CHN, JHH = 9.8 Hz), 3.25 (br, 3H, P(OCH3)3), 3.20 (br,
3H, P(OCH3)3), 2.93 (m, 1H, CH(CH3)2), 1.16 (d, 3H, CH3,
3JHH = 6.2 Hz), 0.91 (m, 6H, CH3 y P(OCH3)3). 13C{1H} NMR (CD2Cl2,
3
293 K, d) 168.5 (d, COCH2, JCP = 3 Hz), 143.9–126.2 (Ph), 77.1 (br,
2
C5H3), 76.2 (d, CPPh2, JCP = 22 Hz), 75.7 (m, C5H3), 74.1 (d, CPPh2,
2
JCP = 32 Hz), 73.4 (CHN), 72.9 (d, C5H3, JCP = 7 Hz), 72.1 (C5H5),
67.3 (OCH2), 54.9 (br, P(OCH3)3), 54.8 (br, P(OCH3)3), 53.3 (m, 2C,
P(OCH3)3), 53.2 (m, 2C, P(OCH3)3), 28.2 (CH(CH3)2), 19.4 (CH3),
16.0 (CH3) ppm. Anal. Calc. for [RuCl2{P(OMe)3}2(FcPN)]: C,
45.30; H, 5.14; N, 1.55. Found: C, 45.73; H, 5.20; N, 1.65%.
Acknowledgements
4.3. Synthesis of mer–trans-[RuCl2(PTA)2{j2(P,N)-FcPN}] (10a)
This work was supported by the Spanish M.C.T. (BQU2003-
00255) Consolider Ingenio 2010 (CSD2007-00006). Cesar A. Madri-
gal and A. García-Fernández thanks the Spanish Ministerio de
Educación, Cultura y Deporte for a scholarship.
PTA (0.033 g, 0.21 mmol) was added to a solution of [RuCl2
(PPh3){j2(P,N)-FcPN}] (0.100 g, 0.10 mmol) in dichloromethane
(10 mL). The mixture was stirred for 2 h at room temperature and then
concentrated under vacuum to a volume of approx. 0.5 mL. Addition of
hexane afforded an orange precipitate. The solvents were decanted and
the solid was washed with hexane (4 ꢂ 10 mL) and dried under re-
duced pressure to afford complex 10a. Yield: 60 mg (62%). 31P{1H}
References
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