Synthesis of novel optically pure quinolyl-β-amino alcohol derivatives from 2-amino thiophenol and chiral α-acetylenic ketones and their IBX-mediated oxidative cleavage to N-Boc quinolyl carboxamides
作者:Gemma Cabarrocas、Montserrat Ventura、Miguel Maestro、José Mahı́a、José M. Villalgordo
DOI:10.1016/s0957-4166(01)00308-1
日期:2001.7
A methodology directed toward the stereoselective synthesis of novel quinolyl glycines is presented. This strategy is based on the cyclocondensation reaction between 2-amino thiophenol 4 and chiral acetylenic ketones of the type 3 containing a latent α-amino acid functionality. The initially formed benzo[b][1,4]thiazepine derivatives 5, readily undergo sulphur extrusion in refluxing toluene to yield
提出了一种针对立体选择性合成新型喹啉基甘氨酸的方法。该策略基于2-氨基苯硫酚4与类型3的含有潜在α-氨基酸官能团的手性炔酮之间的环缩合反应。最初形成的苯并[ b ] [1,4]噻嗪类衍生物5易于在回流的甲苯中进行硫磺挤出,从而生成相应的2,4-二取代的喹啉6。随后恶唑烷开环,然后对氨基进行原位再保护,得到了相应的喹啉基-β-氨基醇8a - 8f以对映体纯形式和良好的总收率。衍生物8原则上是用于通过醇侧链的氧化来合成新型光学纯的喹啉基甘氨酸的合适的前体。然而,使用多种氧化剂和反应条件,这些氨基醇衍生物8不能提供预期的喹啉基甘氨酸10。取而代之的是,通过使8与温和的氧化剂IBX 11反应,发生了氧化的CC裂解反应,生成了N -Boc喹啉基羧酰胺12。