A New Aspect of Magnesium Bromide‐Promoted Enantioselective Aryl Additions of Triaryl(tetrahydrofuran)aluminum to Ketones Catalyzed by a Titanium(IV) Catalyst of<i>trans</i>‐1,2‐Bis(hydroxycamphorsulfonylamino)cyclohexane
作者:Chien‐An Chen、Kuo‐Hui Wu、Han‐Mou Gau
DOI:10.1002/adsc.200800169
日期:2008.7.7
A novel aspect of MgBr2-promoted asymmetric triarylaluminum-tetrahydrofuran [AlAr3(THF)] additions to ketones catalyzed by a titanium catalyst of 20 mol% trans-1,2-bis(hydroxycamphorsulfonylamino)cyclohexane (2) is reported. The catalytic system works excellently for aromatic ketones with either an electron-withdrawing or an electron-donating substituent on the aromatic ring at the 2′-, 3′-, or 4′-positions
报道了由MgBr 2促进的不对称三芳基铝-四氢呋喃[AlAr 3(THF)]加成在由20摩尔%的反式-1,2-双(羟基樟脑磺酰基氨基)环己烷(2)钛催化剂催化的酮中的新变化。催化体系对芳族酮具有出色的作用,该芳族酮在2'-,3'-或4'-位的芳香环上具有吸电子或供电子取代基,可提供≥90%的优异对映选择性的叔醇ee,除了在2'-甲氧基苯乙酮中添加苯基和在乙炔酮中添加4-三甲基甲硅烷基苯基(4-TMSC 6 H 4)的情况。