An individual ligand for a difficult substrate was identified by screening a small library of nine C2-symmetric chiral diphosphine (MediPhos) ligands in a Pd-catalyzed asymmetric allylic amination. The prepared chiral allylamine was then used as a building block in the synthesis of two new proline-derived dipeptide analogs.
通过在 Pd 催化的不对称烯丙基胺化中筛选由 9 个 C 2对称手性二膦 (MediPhos) 配体组成的小型文库,鉴定了用于困难底物的单个配体。然后将制备的手性烯丙胺用作合成两种新的脯氨酸衍生二肽类似物的结构单元。
Chiral Phosphine-Phosphite Ligands in Asymmetric Gold Catalysis: Highly Enantioselective Synthesis of Furo[3,4-<i>d</i>
]-Tetrahydropyridazine Derivatives through [3+3]-Cycloaddition
The AuI‐catalyzed reaction of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with azomethine imines regio‐ and diastereoselectively affords furo[3,4‐d]tetrahydropyridazines in a tandem cyclization/intermolecular [3+3]‐cycloaddition process under mild conditions. By employing a chiral gold catalyst (prepared in situ from a Taddol‐derived phosphine‐phosphite ligand, Me2SAuCl, and AgOTf) high yields and enantioselectivities