Enantioselective Synthesis of Hexahydroisobenzofuran and Hexahydroisoindole Derivatives with Quaternary Stereocenters
作者:Jens Christoffers、Jonas Sluiter、Jan Schmidt
DOI:10.1055/s-0030-1258419
日期:2011.3
Oxo esters with pyrrolidine and tetrahydrofuran rings were converted into optically active isobenzofuran and isoindole derivatives. The key step of the sequence was a copper-catalyzed asymmetric Michael reaction with methyl vinyl ketone and enamines prepared from the oxo esters and l-valine diethylamide. The chiral auxiliary was cleaved from the products during workup and 1,5-diketones with a quaternary
将带有吡咯烷和四氢呋喃环的含氧酯转化为旋光性异苯并呋喃和异吲哚衍生物。该序列的关键步骤是铜催化的不对称迈克尔反应,该反应与甲基乙烯基酮和由含氧酯和1-缬氨酸二乙酰胺制得的烯胺形成。在加工过程中从产物中裂解出手性助剂,得到具有季立体中心的1,5-二酮,ee为97-99%。通过中间的醛醇缩合产物,分两步进行随后的环化反应。 四氢呋喃-吡咯烷-异吲哚-异苯并呋喃-手性-迈克尔加成-季立体中心