Stereoselective Formation of <i>N</i>-Acyliminium Ion via Chiral <i>N</i>,<i>O</i>-Acetal TMS Ether and Its Application to the Synthesis of <i>β</i>-Amino Acids
作者:Dong-Yun Shin、Jae-Kyung Jung、Seung-Yong Seo、Yong-Sil Lee、Seung-Mann Paek、Young Keun Chung、Dong Mok Shin、Young-Ger Suh
DOI:10.1021/ol035289e
日期:2003.10.1
see text] The highly stereoselective synthesis of beta-amino acids via the chiral 4-phenyloxazolidinone-controlled linear N-acyliminium ion reaction has been achieved by employing chiral N,O-acetal TMS ethers. In addition, the mechanism of the excellent stereochemical outcome has been elucidated. The oxazolidinone auxiliary plays a dual role in stereocontrol: the E/Z geometry control of the N-acyliminium
[反应:见正文]通过使用手性N,O-缩醛TMS醚,可以实现通过手性4-苯基恶唑烷酮控制的线性N-酰基亚胺离子反应进行的β-氨基酸的高度立体选择性合成。另外,已经阐明了优异的立体化学结果的机制。恶唑烷酮辅助剂在立体控制中起着双重作用:通过最初的立体选择性酰胺还原反应诱导的N-酰基亚胺离子的E / Z几何控制,从而导致手性N,O-缩醛TMS醚,以及对亲核试剂攻击的表面控制N-酰基亚胺离子反应。