Chemical Product Research and Development, Eli Lilly and Company, Indianapolis, Indiana 46285, USA.
Org Lett. 2012 Feb 17;14(4):1038-41. doi: 10.1021/ol203264a. Epub 2012 Jan 30.
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.
使用原位形成的铑-Josiphos 催化剂实现了四取代的α,β-不饱和酮的不对称氢化。通过添加催化量的三氟甲磺酸锌,反应得到增强,同时显著提高了转化频率,抑制了产物的差向异构化。