posted on 2012-02-17, 00:00authored byJoel R. Calvin, Michael O. Frederick, Dana L. T. Laird, Jacob R. Remacle, Scott A. May
The asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketones has been accomplished using an in situ formed rhodium-Josiphos catalyst. The reaction is enhanced by addition of catalytic zinc(II) triflate, which significantly improves turnover frequency while suppressing epimerization of the products.