使用PdCl 2 / PAr 3(Ar = C 6 H 4 - p -CF 3)和ZnEt 2在CO的1个大气压下,分子内方式进行的烯丙基的芳基羧化反应以高产率得到相应的β,γ-不饱和羧酸。2。环化/羧化序列的中间被认为是亲核η 1 -allylethylpalladium,其发生反应用CO 2在钯的γ位置。所获得的产物可以有效地转化为3-取代的吲哚-2-羧酸酯衍生物。还证实了从羧化产物一锅法合成苯乙烯基香菜碱(一种β-咔啉生物碱)。
Pd-Catalyzed Highly Regio- and Stereoselective Formation of C–C Double Bonds: An Efficient Method for the Synthesis of Benzofuran-, Dihydrobenzofuran-, and Indoline-Containing Alkenes
A highly regio- and stereoselective C–C double bond formation reactionvia Pd-catalyzed Heck-type cascade process with N-tosylhydrazones has been developed. Various N-tosylhydrazones derived from both ketones and aldehydes are found to be efficient substrates to provide di- and trisubstitutedolefins with high regio- and stereoselectivity. Furthermore, this reaction has a good functional group tolerance
Palladium-Catalyzed Carboacylation of Alkenes by Using Acylchromates as Acyl Donors
作者:Motoki Yamane、Yuko Kubota、Koichi Narasaka
DOI:10.1246/bcsj.78.331
日期:2005.2
Palladium-catalyzed arylacylation of alkenes proceeds by employing acylchromates as acyl donors. When active alkenes such as norbornene and methoxyallene are treated with an aryl iodide, an acylchromate, and a catalytic amount of Pd(OAc)2/2P(o-Tol)3, arylacylation of these alkenes proceeds at room temperature. From aryl iodides having an intramolecular alkene moiety, cyclization–acylation products are obtained via intramolecular arylpalladation followed by acylation with acylchromates.
Enantioselective Construction of 1<i>H</i>-Isoindoles Containing Tri- and Difluoromethylated Quaternary Stereogenic Centers via Palladium-Catalyzed C–H Bond Imidoylation
enantioselective synthesis of 1H-isoindoles containing tri- and difluoromethylated quaternary stereogenic centers through a palladium-catalyzed desymmetric C–H bond imidoylation has been developed. α,α-Diaryl tri- and difluoroethylated isocyanides acted as powerful precursors of chiral 1H-isoindoles, in which the fluoroalkyl group was proven to play a crucial role in both the stereochemistry and reaction efficiency
π-Allylpalladium intermediates are known to participate efficiently in transformations involving nucleophilic species. Exploring these processes, we have developed a method for the preparation of allyl acetates via palladium-catalysed functionalisation of allenes and 1,3-dienes. Reactions of aryl iodides with either of these two classes of compounds and excess sodium acetate in the presence of Pd(OAc)2
Abstract A palladium-catalyzed regioselective three-component cascade reaction of carbondioxide, amines and allenes has been developed, providing an expedient and practical method for the construction of a range of functionalized carbamates containing dihydrobenzofuran or indole moiety in moderate to excellent yields. The broad substrate scope, good functional group tolerance and excellent chemo-