Palladium-Catalyzed Cross-Coupling Reactions of Carboxylic Anhydrides with Organozinc Reagents
作者:Donghui Wang、Zhaoguo Zhang
DOI:10.1021/ol035801w
日期:2003.11.1
[reaction: see text] Negishi-type cross-coupling reaction was effected by employing organozincs and anhydrides or mixedanhydrides that formed in situ fromsodiumsalts of the corresponding acids and ethyl chloroformate under the catalysis of palladium(0). A general method for preparing symmetrical/unsymmetrical ketones was developed.
The syntheses of 32 complexes of the type (η-C5H5)2Ti(OOCC6H4X)2 are reported together with their mass, 1H NMR, 13C NMR, mid- and far-IR spectra. The data are consistent with a model in which the TiOOC bond strength (weaker than that of TiCp and TiHal) is stabilized by electron-withdrawing substituents X on the phenyl rings. The electronic influence of X also extends into the cyclopentadienyl rings
的类型的32种复合物的合成(η-C 5 H ^ 5)2的Ti(OOCC 6 H ^ 4 X)2与它们的质量,一起报告1 H NMR,13 C NMR,中期和远红外光谱。该数据与通过苯环上的吸电子取代基X稳定了TiOOC键强度(比TiCp和TiHal的强度弱)的模型一致。X的电子影响也延伸到环戊二烯基环中。
Weak Coordinating Carboxylate Directed Rhodium(III)-Catalyzed C–H Activation: Switchable Decarboxylative Heck-Type and [4 + 1] Annulation Reactions with Maleimides
group assisted C–H activation with maleimides leading to novel and switchable decarboxylative Heck-type and [4 + 1] annulation products catalyzed by Rh(III) has been reported. In these reactions, solvents play a vital role in switching the selectivity. An aprotic solvent, THF, leads to the decarboxylative Heck-type product while the protic solvent, TFE, results in the [4 + 1] annulation product. The
One-step process for preparing anhydrous, organic acid alkali or alkaline earth metal salts by contacting and reacting an organic or polymeric acid fluoride, anhydride or ester and an organic alkali or alkaline earth metal silanolate.