作者:Alois Fürstner、Nongyuan Shi
DOI:10.1021/ja9625236
日期:1996.1.1
chromium-catalyzed additions of organic halides to aldehydes (“Nozaki−Hiyama−Kishi reactions”). The reactions are mediated by trimethylchlorosilane, and the active Cr2+ species is constantly recycled by means of nontoxic, commercial manganese powder as the stoichiometric reductant. This method nicely applies to different substituted aryl, heteroaryl, alkynyl, alkenyl, and allyl halides as well as to alkenyl triflates
描述了一种程序,该程序允许首次将有机卤化物添加到醛中(“Nozaki-Hiyama-Kishi 反应”)。反应由三甲基氯硅烷介导,活性 Cr2+ 物种通过无毒的商业锰粉作为化学计量还原剂不断回收。该方法很好地适用于不同的取代芳基、杂芳基、炔基、烯基和烯丙基卤化物以及烯基三氟甲磺酸酯作为起始原料,并在效率、实用性以及化学和非对映选择性方面与其化学计量先例相媲美。具体而言,已经证明巴豆基溴与各种醛的加成是高度立体收敛的,即 无论起始卤化物是 (E)- 还是 (Z)- 构型,均以优异的非对映体过量获得各自的反构型高烯丙醇。根据可能的催化循环,CrCl2(cat.) 或 CrCl3(cat) 都转...