Abstract
The intrinsic selectivity of cinchonidine-modified Pt/alumina is poor in the hydrogenation of 3,5-di-(trifluoromethyl)-acetophenone but stirring of the catalyst system in toluene under nitrogen prior to reaction more than triples the ee. SEM and TEM analysis revealed dramatic restructuring of the catalyst and the Pt particles. We propose that the interaction of the hydroxy methyl-quinoline fragment (“anchoring moiety”) of cinchonidine with Pt is responsible for the restructuring. Reductive pretreatment at elevated temperature as well as the attrition induced by stirring in toluene accelerate the process. The higher ee is attributed to morphological changes of Pt, leading to the development of a more “selective” surface. The chirality of cinchonidine is unimportant in the restructuring and no correlation between the size of Pt particles and the ee has been found.
Similar content being viewed by others
References
Y. Orito, S. Imai and S. Niwa, J. Chem. Soc. Jpn (1979) 1118.
Y. Orito, S. Imai and S. Niwa, J. Chem. Soc. Jpn (1980) 670.
H.U. Blaser, H.P. Jalett, D.M. Monti, A. Baiker and J.T. Wehrli, Stud. Surf. Sci. Catal. 67 (1991) 147.
P.B. Wells and A.G. Wilkinson, Top. Catal. 5 (1998) 39.
A. Baiker, J. Mol. Catal., A: Chem. 163 (2000) 205.
M. von Arx, T. Mallat and A. Baiker, Top. Catal. 19 (2002) 75.
A. Baiker, J. Mol. Catal., A: Chem. 115 (1997) 473.
M. Studer, H.U. Blaser and C. Exner, Adv. Synth. Catal. 345 (2003) 45.
J.T. Wehrli, A. Baiker, D.M. Monti and H.U. Blaser, J. Mol. Catal. 49 (1989) 195.
J.T. Wehrli, A. Baiker, M. Monti and H.U. Blaser, J. Mol. Catal. 61 (1990) 207.
H. Bönnemann and G.A. Braun, Angew. Chem., Int. Ed. Engl. 35 (1996) 1992.
H.U. Blaser, H.P. Jalett, D.M. Monti and J.T. Wehrli, Appl. Catal. 52 (1989) 19.
H.U. Blaser, H.P. Jalett, D.M. Monti, J.F. Reber and J.T. Wehrli, Stud. Surf. Sci. Catal. 41 (1988) 153.
T. Mallat, M. Bodmer and A. Baiker, Catal. Lett. 44 (1997) 95.
M. Schürch, O. Schwalm, T. Mallat, J. Weber and A. Baiker, J. Catal. 169 (1997) 275.
T. Mallat, S. Frauchiger, P.J. Kooyman, M. Schurch and A. Baiker, Catal. Lett. 63 (1999) 121.
A. Szabo, N. Künzle, T. Mallat and A. Baiker, Tetrahedron: Asymmetry 10 (1999) 61.
B. Török, K. Felföldi, K. Balàzsik and M. Bartók, Chem. Commun. (1999) 1725.
R. Hess, T. Mallat and A. Baiker, J. Catal. 218 (2003) 453.
B. Török, K. Balàzsik, M. Török, G. Szöllösi and M. Bartók, Ultrason. Sonochem. 7 (2000) 151.
B. Török, K. Balàzsik, M. Török, K. Felföldi and M. Bartók, Catal. Lett. 81 (2002) 55.
A. Tungler, React. Kinet. Catal. Lett. 74 (2001) 271.
M. Schunack, L. Petersen, A. Kuhnle, E. Laegsgaard, I. Stensgaard, I. Johannsen and F. Besenbacher, Phys. Rev. Lett. 86 (2001) 456.
M. Schunack, E. Laegsgaard, I. Stensgaard, I. Johannsen and F. Besenbacher, Angew. Chem., Int. Ed. Engl. 40 (2001) 2623.
R.P. Singh, B. Twamley, L. Fabry-Asztalos, D.S. Matteson and J.M. Shreeve, J. Org. Chem. 65 (2000) 8123.
A.D. Allen, V.M. Kanagasabapathy and T.T. Tidwell, J. Am. Chem. Soc. 107 (1985) 4513.
A. Borodzinski and M. Bonarowska, Langmuir 13 (1997) 5613.
R. Hess, A. Vargas, T. Bürgi, T. Mallat and A. Baiker, J. Catal. submitted (2003)
D. Ferri, T. Bürgi and A. Baiker, Chem. Commun. (2001) 1172.
D. Ferri and T. Bürgi, J. Am. Chem. Soc. 123 (2001) 12074.
G.D.H. Dijkstra, R.M. Kellogg, H. Wynberg, J.S. Svedsen, I. Marko and K.B. Sharpless, J. Am. Chem. Soc. 111 (1989) 8069.
M. Garland, Stud. Surf. Sci. Catal. 59 (1991) 177.
G.A. Somorjai, Catal. Lett. 12 (1992) 17.
G.A. Somorjai, Langmuir 7 (1991) 3176.
W.F. Maier, S.J. Chette, R.S. Rai and G. Thomas, J. Am. Chem. Soc. 108 (1986) 2608.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Hess, R., Krumeich, F., Mallat, T. et al. Cinchonidine-Induced Restructuring of Pt/Al2O3 During Enantioselective Hydrogenation. Catalysis Letters 92, 141–148 (2004). https://doi.org/10.1023/B:CATL.0000014336.66209.5a
Issue Date:
DOI: https://doi.org/10.1023/B:CATL.0000014336.66209.5a