Department of Chemistry, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan.
Org Lett. 2011 Apr 1;13(7):1860-3. doi: 10.1021/ol200374m. Epub 2011 Mar 10.
A biphenol-based chiral phosphoric acid bearing a 9-anthryl group at each of the 3,3'-positions catalyzed the asymmetric Mannich-type reaction of N-Boc imine with difluoroenol silyl ethers in the presence of MS3A in THF to afford β-amino-α,α-difluoroketones in good yields and with excellent enantioselectivities. Optically pure 3,3-difluoroazetidin-2-one was readily synthesized from the Mannich-adduct.
一种基于双酚的手性磷酸，在 3,3'- 位的每个位置上都带有 9-蒽基，在 MS3A 的存在下，在四氢呋喃中催化 N-Boc 亚胺与二氟烯醇硅醚的不对称 Mannich 型反应，以高产率和优异的对映选择性得到 β-氨基-α,α-二氟酮。手性 Mannich 加成产物很容易转化为光学纯的 3,3-二氟氮杂环丁酮。
