Matharu Daljit S, Martins José E D, Wills Martin
Department of Chemistry, The University of Warwick, Coventry, UK.
Chem Asian J. 2008 Sep 1;3(8-9):1374-83. doi: 10.1002/asia.200800189.
Rh(III) catalysts containing a tetramethylcyclopentadienyl group linked by a 'tether' to a tosylated diamine ligand have previously been reported by our group for the asymmetric transfer hydrogenation (ATH) of ketones. The extension of these catalysts to the asymmetric reduction of imines, as well as to more highly functionalized substrates is reported. In some cases, the catalysts give better ee values than other methods for these transformations at lower catalyst loadings. The introduction of a methoxy group into the tethering aryl ring does not negate the performance of the catalyst, thus opening up a route to supported derivatives.
我们小组之前曾报道过含有通过“系链”连接到甲苯磺酰化二胺配体上的四甲基环戊二烯基的铑(III)催化剂用于酮的不对称转移氢化(ATH)反应。本文报道了将这些催化剂扩展至亚胺的不对称还原反应以及用于更多高官能化底物的反应。在某些情况下，这些催化剂在较低催化剂负载量下比其他用于这些转化反应的方法能给出更好的对映体过量值(ee值)。在连接芳环中引入甲氧基并不会削弱催化剂的性能，从而开辟了一条制备负载型衍生物的途径。
