邻溴苯甲酰胺1 a – m在K 2 CO 3和[PdCl 2(PPh 3)2 ]催化剂的存在下的多米诺反应允许选择性地利用菲啶酮2或新的1-羧酰胺菲啶酮3,具体取决于分别是DMF或1,4-二恶烷。对反应参数的研究为碱解离和溶剂极性与所观察到的选择性之间的直接相关提供了第一个例子。此外,机理研究(NMR光谱和ESI-MS监测)使我们能够表征Pd II palladacycle4和联芳基物质是这两个多米诺骨牌工艺的常见中间体。在此基础上,可以设想通过在Pd II palladacycle 4中氧化添加1后生成Pd IV络合物来形成C(sp 2)C(sp 2)键,这一原理得到DFT计算的支持。提出了一般的催化循环来解释这些观察结果。
Efficient Synthesis of Phenanthridinone Derivatives via a Palladium-Catalyzed Coupling Process
摘要:
A palladium-mediated domino reaction was developed to conveniently synthesize phenanthridinone derivatives. Phosphine ligand 1 strongly promotes the domino process, which includes aryl-aryl coupling and C-N bond formations concomitant with a deamidation reaction. The versatility and applicability to a broad range of substrates make this reaction useful for the development of bioactive derivatives.
Palladium-Catalyzed Annulation of Arynes by <i>o</i>-Halobenzamides: Synthesis of Phenanthridinones
作者:Chun Lu、Anton V. Dubrovskiy、Richard C. Larock
DOI:10.1021/jo3016192
日期:2012.10.5
The palladium-catalyzedannulation of arynes by substituted o-halobenzamides produces N-substituted phenanthridinones in good yields. This methodology provides this important heterocyclic ring system in a single step by simultaneous C–C and C–N bond formation, under relatively mild reaction conditions, and tolerates a variety of functional groups.
Preparation of benzisothiazolones from 2-bromobenzamides and sulfur under copper catalysis conditions
作者:V. Krasikova、M. Katkevics
DOI:10.1007/s10593-013-1193-5
日期:2013.2
A convenient two-stage method has been developed for preparing benz[d]isothiazol-3(2H)-ones from 2-bromobenzamides and sulfur in a one-pot process under copper catalysis conditions. The method is suitable for the synthesis of N-aryl-, benzyl-, and alkyl-substituted benzisothiazolones. The yields of the benzisothiazolones depend on the nature of the starting amide and can reach 91%.
已经开发了一种方便的两步法,用于在铜催化条件下通过一锅法从2-溴苯甲酰胺和硫制备苯并[ d ]异噻唑-3(2 H)-一。该方法适合于合成N-芳基-,苄基-和烷基取代的苯并异噻唑酮。苯并异噻唑酮的产率取决于起始酰胺的性质,可以达到91%。
Synthesis of Cyclopropanes by Intramolecular Attack ofN-Nucleophiles on the Central Carbon of (π-Allyl)palladium Complexes
amounts of palladium(0) complexes to form cyclopropanes such as 3a. This reaction is believed to proceed via an intermediate palladacyclobutane and is the first example of a noncarbon nucleophile attack on the centre carbon of an (η3-allyl)palladium complex leading, by reductive elimination, to cyclopropanes. The regiochemistry of the nucleophilicattack (central versus terminal carbon) depends on the nature
Electron-poor alkenes such as alkyl acrylates have been found to insert into the aromatic carbon—palladium bond in orthobromobenzamides under the conditions of the Heck reaction. For primary and secondary benzamides a further palladium-catalysed reaction occurs to yield 3-substituted, or 2,3-disubstituted phthalimidines.
A one-step Pd-catalyzed reaction performed on an o-bromobenzamide permitted the selective formation of either phenanthridinones 2 via an ipso substitution or new phenanthridinone-1-carboxamides 3 through a direct N-arylation. A direct correlation between the solvent polarity and the carbonate base on the selectivity has been observed. The proposed catalytic cycle involves the initial formation of a common Intermediate and depends on the base assistance.