Enantioselective hydrogenation of activated ketones in the presence of Pt-Cinchona catalysts. Is the proton transfer concept valid?
نویسندگان
چکیده
Experimental evidences related to the proton transfer in the catalytic system Pt-Cinchona alkaloids for enantioselective hydrogenation of activated ketones were collected and analyzed. Both new and earlier results indicate that in aprotic media direct transfer of proton from platinum to the substrate with the involvement of quinuclidine nitrogen as a general rule can be questioned.
منابع مشابه
Enantioselective Hydrogenation on Cinchona-Modified Metal Catalysts:Mechanistic Implications of Acid Additive
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