1,2-Stereochemical Induction in the Pd<sup>II</sup>-Catalyzed Conjugate Addition of Boronic Acids
作者:Silvia Roscales、Francisco Sánchez、Aurelio G. Csákÿ
DOI:10.1002/ejoc.201403488
日期:2015.3
2-chiral induction of the conjugate addition of boronic acids to enantiopure α,β-unsaturated ketones and esters without competition from the Mirozoki–Heck reaction. Bedford's palladacycle was found to control the stereoselectivity without the need for additional chiral ligands. We report that the PdII-catalyzed conjugate addition reaction between boronic acids and acyclic ketones or esters that bear a hydroxyl
钯 (II) 催化已用于底物控制的 1,2-手性诱导硼酸与对映体纯 α,β-不饱和酮和酯的共轭加成反应,而不受 Mirozoki-Heck 反应的竞争。发现贝德福德的钯环无需额外的手性配体即可控制立体选择性。我们报告说,硼酸和在其 γ 位带有羟基取代基的无环酮或酯(甘油醛衍生物)之间的 PdII 催化的共轭加成反应可以提供高水平的抗立体选择,与之前报道的使用更昂贵的 RhI 催化剂相比. 另一方面,使用在其 γ 位带有氨基取代基的无环酯(丝氨酸衍生物)观察到高水平的顺式立体选择性。在这种情况下,