在叔丁醇钾和有机分子作为催化剂存在的情况下,已经开发出一种涉及邻卤代N芳基苄胺的“无过渡金属”分子内联芳基偶合的方法。该反应似乎通过KO t Bu促进的分子内均溶芳族取代(HAS)进行。有趣的是,这种联芳基偶合在叔丁醇钾作为唯一促进剂的情况下也起作用。在进一步扩展我们的方法时,我们发现N-酰基2-溴-N-芳基苄胺经历了一锅N-脱保护/联芳基偶联,然后进行氧化,因此提供了通往菲啶和苯并[ c ]菲啶骨架的快速途径。该策略已被应用于简明的金莲花科生物碱的合成。oxoassoanine(1B),anhydrolycorinone(1D),5,6- dihydrobicolorine(2D),trispheridine(2B),和苯并[ C ^ ]菲啶生物碱dihydronitidine(图3b),dihydrochelerythidine(3D),dihydroavicine(3F),norni
Pd-Catalyzed Semmler–Wolff Reactions for the Conversion of Substituted Cyclohexenone Oximes to Primary Anilines
作者:Wan Pyo Hong、Andrei V. Iosub、Shannon S. Stahl
DOI:10.1021/ja4073172
日期:2013.9.18
Homogeneous Pd catalysts have been identified for the conversion of cyclohexenone and tetralone O-pivaloyl oximes to the corresponding primary anilines and 1-aminonaphthalenes. This method is inspired by the Semmler-Wolff reaction, a classic method that exhibits limited synthetic utility owing to its forcing conditions, narrow scope, and low product yields. The oxime N-O bond undergoes oxidative addition to Pd-0(PCy3)(2), and the product of this step has been characterized by X-ray crystallography and shown to undergo dehydrogenation to afford the aniline product.
Smidrkal, Jan, Collection of Czechoslovak Chemical Communications, 1984, vol. 49, # 6, p. 1412 - 1420