Preparation of Pyrrolidine-Based PDE4 Inhibitors via Enantioselective Conjugate Addition of α-Substituted Malonates to Aromatic Nitroalkenes
作者:Paul J. Nichols、John A. DeMattei、Bradley R. Barnett、Nicole A. LeFur、Tsung-Hsun Chuang、Anthony D. Piscopio、Kevin Koch
DOI:10.1021/ol060398p
日期:2006.3.1
[reaction: see text] The enantioselective conjugate addition of alpha-substituted malonates to aromatic nitroalkenes generates a stereocenter at the carbon bearing the aromatic group and an adjacent prochiral center from the alpha-substituted malonate. Nitro reduction followed by diastereoselective cyclization provides pyrrolidinones with two contiguous stereocenters, one of which is quaternary. This
[反应:见正文]α-取代的丙二酸酯的对映选择性共轭加成到芳族硝基烯烃上,在带有芳族基团的碳上产生一个立体中心,并与α-取代的丙二酸酯相邻的前手性中心产生一个立体中心。硝基还原后非对映选择性环化为吡咯烷酮提供了两个连续的立体中心,其中之一是四元的。该序列用于制备PDE4抑制剂IC86518。对映选择性迈克尔加成反应的其他例子说明了反应的范围。