Audrey Nowicki et al.
FULL PAPERS
Experimental Section
General Procedure for Hydrogenation under
Hydrogen Pressure
Materials
The stainless steel autoclave was charged with the previous-
ly prepared aqueous suspension of Ru(0) (10 mL) and a
magnetic stirrer. The appropriate substrate (3.810À3 mol,
100 equivs.) was added into the autoclave and dihydrogen
was admitted to the system at constant pressure (up to
30 bar). The mixture was stirred with a magnetic stir bar or
with a magnetic stirrer of powerful torque up to 95 Ncm
equipped with a gas projection impeller (Top-Industries
SA). Samples for gas chromatographic analysis were re-
moved from time to time. The TOF was determined for
100% conversion.
Ruthenium chloride hydrate was obtained from Strem
Chemicals. Sodium borohydride and all arenes were pur-
chased from Aldrich or Acros and used without further pu-
rification. Water was distilled twice before use by conven-
tional method. The surfactant HEA16Cl was prepared as
previously reported and was fully characterized.[10]
Analytical Procedures
TEM analysis: The transmission electronic microscopic
studies were conducted using a Philips CM 12 transmission
electron microscope at 100 keV (UMR CNRS 6026 – Uni-
versity of Rennes I). Samples were prepared by a dropwise
addition of the stabilized ruthenium colloids in water onto a
copper sample mesh covered with carbon. The colloidal dis-
persion was partially removed after 1 min using cellulose
before transferring to the microscope. The picture is ob-
tained at 80,000. Measurement of about 200 particles was
made with the program SCION Image (NIH) and was ana-
lyzed with the Excel program providing the histograms of
the nanoparticles size distribution
References
[1] J. G. de Vries, C. J. Elsevier (Eds), The Handbook of
U
Homogeneous Hydrogenation, Wiley-VCH, Weinheim,
2006.
[2] H. Nagahara, M. Ono, M. Konishi, Y. Fukuoka, Appl.
Surf. Sc. 1997, 121/122, 448.
[3] K. Weissermel, H. J. Arpe, Industrial Organic Chemis-
try, VCH, New York, 2nd edn., 1993, p 343.
[4] A. Corma, A. Martinez, V. Martinez-Soria, J. Catal.
1997, 169, 480.
Gas chromatography: All analyses were performed using
a Carlo Erba GC 6000 with an FID detector equipped with
a Factor Four column (30 m, 0.25 mm i.d.). Parameters were
as follows: initial temperature, 408C; initial time, 10 min;
[5] A. M. Casillas, T. Hiura, N. Li, A. E. Nel, Ann. Allergy
Asthma Immunol. 1999, 83, 624.
[6] K. S. Weddle, J. D. Aiken III, R. G. Finke, J. Am.
Chem. Soc. 1998, 120, 5653.
[7] P. J. Dyson, Dalton Trans. 2003, 2964.
[8] T. J. Geldbach, P. J. Dyson, J. Organomet. Chem. 2005,
690, 3552.
ramp, 108CminÀ1
; final temperature, 808C; final time,
30 min; injector temperature, 2208C; detector temperature,
2508C.
Catalytic Tests
[9] Stabilized noble metal nanoparticles: An unavoidable
family of catalysts for arene derivatives hydrogenation,
A. Roucoux, in: Surface and Interfacial Organometallic
Chemistry and Catalysis, (Eds.: C. CopØret, B. Chau-
dret), Topics in Organometallic Chemistry, Springer-
Verlag, Heidelberg, 2005, Vol. 16, p 261.
[10] A. Roucoux, J. Schulz, H. Patin, Adv. Synth. Catal.
2003, 345, 222.
[11] J. Schulz, A. Roucoux, H. Patin, Chem. Eur. J, 2000, 6,
618.
[12] V. MØvellec, A. Roucoux, E. Ramirez, K. Philipot, B.
Chaudret, Adv. Synth. Catal. 2004, 346, 72.
[13] J. A. Widegren, R. G. Finke, J. Mol. Catal. A: Chem.
2003, 198, 317.
Synthesis of the aqueous ruthenium(0) suspension: The
aqueous suspensions of ruthenium nanoparticles were pre-
pared according to our previously described rhodium sus-
pension synthesis.[11]
An aqueous solution of surfactant HEA16Cl (544 mg,
1.710À3 molLÀ1 in 40 mL H2O) was added in a flask con-
taining 16 mg of sodium borohydride (4.210À4 mol). Then
this solution was quickly added under vigorous stirring to an
aqueous solution (10 mL) of RuCl3·1.8H2O(50 mg, 1.7
10À4 mol) to obtain an aqueous Ru(0) colloidal suspension
(50 mL). The reduction occurs instantaneously and is cha-
racterized by a color change from yellow-brown to black.
The obtained suspensions are stable for several weeks.
[14] J. A. Widegren, R. G. Finke, Inorg. Chem. 2002, 41,
1558 and 1625.
[15] B. LØger, A. Nowicki, J. P. Rolland, A. Roucoux, J.
Mol. Catal. A: Chem. 2007, 266, 221.
2330
ꢀ 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2007, 349, 2326 – 2330