An Improved Asymmetrically-Modified Nickel Catalyst Prepared from Ultrasonicated Raney Nickel

Abstract

Abstract The ultrasonic irradiation of Raney nickel catalyst in water followed by the removal of the resulting turbid supernatant gave an excellent nickel catalyst (RNi-U) which generated an asymmetrically-modified nickel catalyst. An EPMA (SEM-EDX) study indicated that RNi-U consisted of a fairly pure nickel surface of homogeneous size. Tartaric acid–NaBr-modified RNi-U (TA–NaBr–MRNi-U) showed a high enantio-differentiating ability as well as reactivity in the hydrogenation of prochiral ketones such as 1,3-diones and 3-oxoalkanoic acid esters.