Asymmetric Rhodium-Catalyzed Hydrogenation Meets Gold-Catalyzed Cyclization: Enantioselective Synthesis of 8-Hydroxytetrahydroisoquinolines
作者:A. Stephen K. Hashmi、Patrick Haufe、Christoph Schmid、Andreas Rivas Nass、Wolfgang Frey
DOI:10.1002/chem.200600192
日期:2006.7.5
The absolute configuration of the newly formed stereogenic center was determined by anomalous diffraction to be R. These chiral furyl alanines were transferred into 8-hydroxytetrahydroisoquinolines by employing gold-catalyzed arene synthesis as the key step. During the latter reaction sequence, also including either a propargylation or a reduction, a protection of the hydroxy group, and a subsequent propargylation
将不同的呋喃基取代的(Z)-脱氢氨基酸衍生物用铑/ Mandyphos(OMe)系统氢化,得到80%至98%之间的对映体过量。通过异常衍射确定新形成的立体异构中心的绝对构型为R。通过手性金催化的芳烃合成,将这些手性呋喃基丙氨酸转移至8-羟基四氢异喹啉中。在后面的反应序列中,也包括炔丙基化或还原,羟基的保护以及随后的炔丙基化,未观察到立体异构中心的外消旋化。使用非常富电子的呋喃,而不是作为产物的8-羟基四氢喹啉,在相同的反应条件下形成了带有环外CC双键的七元环呋喃。