Aikawa Kohsuke, Yabuuchi Kohei, Torii Kota, Mikami Koichi
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Beilstein J Org Chem. 2018 Mar 7;14:576-582. doi: 10.3762/bjoc.14.44. eCollection 2018.
The catalytic asymmetric methylation of fluoroalkylated pyruvates is shown with dimethylzinc as a methylating reagent in the presence of a copper catalyst bearing a chiral phosphine ligand. This is the first catalytic asymmetric methylation to synthesize various α-fluoroalkylated tertiary alcohols with CF, CFH, CFBr, and -C F ( = 2, 3, 8) groups in good-to-high yields and enantioselectivities. Axial backbones and substituents on phosphorus atoms of chiral phosphine ligands critically influence the enantioselectivity. Moreover, the methylation of simple perfluoroalkylated ketones is found to be facilitated by only chiral phosphines without copper.
在带有手性膦配体的铜催化剂存在下，以二甲基锌作为甲基化试剂，实现了氟烷基化丙酮酸酯的催化不对称甲基化反应。这是首例催化不对称甲基化反应，能够以良好至高的产率和对映选择性合成带有CF、CFH、CFBr和-CF（=2,3,8）基团的各种α-氟烷基化叔醇。手性膦配体磷原子上的轴向主链和取代基对映选择性有至关重要的影响。此外，发现仅使用手性膦而无铜时，简单全氟烷基化酮的甲基化反应更容易进行。
