Note to the Editor: The enantioselective hydrogenation of 1-phenyl ethanol and of ketones using Pt and Pd supported on natural polymers: work of the group of Ying-Yang Jiang, Institute of Chemistry, Chinese Academy of Science, China

✍ Scribed by Martin Studer; Hans-Ulrich Blaser

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 38 KB
• Volume: 172
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(01)00158-3

✦ Synopsis

In [1], the group of Jiang described the asymmetric hydrogenation of alpha 1-phenyl ethanol on a heterogeneous Pt-chitin-silica catalyst. The paper is related to work published earlier, where the enantioselective hydrogenation of ketones with similar chiral heterogeneous catalysts (Pt and Pd supported on chitosan and wool) is described. [2][3][4]. In all papers, the reported enantioselectivities are very high and in some cases up to 100%, even for very simple aliphatic ketones! If these results were genuine this would be absolutely unprecedented and a true sensation. Up to now, metals deposited on chiral supports were not very effective enantioselective catalysts (for a review see [5]). Even more importantly, only very few homogeneous or heterogeneous catalysts give e.e.'s > 85% for the hydrogenation of simple ketones like methyl isobutyl ketone [6,7].

However, when we saw how the e.e.'s were determined we came to the conclusion that some results might be experimental artifacts. Our main concern is the following: in all the four papers, the only method used for the determination of the * Corresponding author.