Bieniek Michał, Bujok Robert, Cabaj Maciej, Lugan Noël, Lavigne Guy, Arlt Dieter, Grela Karol
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
J Am Chem Soc. 2006 Oct 25;128(42):13652-3. doi: 10.1021/ja063186w.
A 95% yield in the cross metathesis of acrylonitrile with a model olefin is achieved at 25 degrees C with only 3 mol % of the new air-stable ruthenium catalyst 1f shown in the enclosed structural diagram. Even more remarkable are the performances of its boosted version 1g incorporating an electron-withdrawing group. Both these new enhanced versions of Hoveyda catalyst are readily available from Grubbs second generation precatalyst upon reaction with a styrenyl ether the end group of which has been functionalized by an ester function. The latter acts as a weakly coordinating ligand allowing to reach a desirable balance between antinomic properties such as the catalyst's stability, a high activity for challenging substrates, and a high initiation rate.
在25摄氏度下，使用仅3摩尔%的如附图结构示意图所示的新型空气稳定钌催化剂1f，丙烯腈与模型烯烃的交叉复分解反应产率可达95%。其含有吸电子基团的增强版1g的性能更引人注目。这两种新型霍维达催化剂的增强版都可通过与末端经酯官能团官能化的苯乙烯基醚反应，从格拉布第二代预催化剂轻松制得。后者作为弱配位配体，能在诸如催化剂稳定性、对挑战性底物的高活性和高引发速率等矛盾性质之间达到理想平衡。
