Chiral Phosphine-Phosphite Ligands in Asymmetric Gold Catalysis: Highly Enantioselective Synthesis of Furo[3,4-<i>d</i>
]-Tetrahydropyridazine Derivatives through [3+3]-Cycloaddition
作者:Qingwei Du、Jörg-Martin Neudörfl、Hans-Günther Schmalz
DOI:10.1002/chem.201800042
日期:2018.2.16
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
2-(1-炔基)-2-α-1-酮与偶氮亚胺亚胺区域和非对映选择性的Au I催化反应,以串联环化/分子间[3 + 3]的形式提供了呋喃[3,4-d]四氢哒嗪。在温和条件下的环加过程。通过使用手性金催化剂(由Taddol衍生的膦-亚磷酸酯配体,Me 2 SAuCl和AgOTf原位制备),可获得高收率和对映选择性(最高94%的收率,最高96%的 ee)。该方法为取代的杂三环呋喃衍生物提供了有效的模块化途径,并且可以容易地按比例放大(使用仅0.15mol%的催化剂负载)。