Rhodium(III)-Catalyzed Direct C–H Arylation of Various Acyclic Enamides with Arylsilanes
作者:Xiaolan Li、Kai Sun、Wenjuan Shen、Yong Zhang、Ming-Zhu Lu、Xuzhong Luo、Haiqing Luo
DOI:10.1021/acs.orglett.0c03578
日期:2021.1.1
The stereoselective β-C(sp2)–H arylation of various acyclic enamides with arylsilanes via Rh(III)-catalyzed cross-coupling reaction was illustrated. The methodology was characterized by extraordinary efficacy and stereoselectivity, a wide scope of substrates, good functional group tolerance, and the adoption of environmentally friendly arylsilanes. The utility of this present method was evidenced by
Cu-Catalyzed Coupling of <i>O</i>
-Acyl Oximes with Isatins: Domino Rearrangement Strategy for Direct Access to Quinoline-4-Carboxamides by C-N Bond Cleavage
A mild domino rearrangement strategy for the direct access to substituted quinoline‐4‐carboxamides has been developed. This copper‐catalyzed coupling reaction of O‐acyl oximes with isatins in the presence of molecular oxygen as the sole oxidizing agent proceeds through a ring expansion of the isatins through cleavage of the two CN bonds
Beckmannrearrangement of ketoxime catalyzed by acidic ionic liquid-N-methyl-imidazolium hydrosulfate was studied. Rearrangement of benzophenone oxime gave the desirable product with 45% yield at 90 °C. When co-catalyst P₂O₅ was added, the yield could be improved to 91%. The catalyst could be reused three cycles with the same efficiency. Finally, reactions of other ketoximes were also investigated
研究了酸性离子液体-N-甲基咪唑鎓硫酸氢盐催化酮肟的贝克曼重排。二苯甲酮肟的重排得到所需产物,在90℃下产率为45%。当加入助催化剂P 2 O 3时,产率可以提高到91%。该催化剂可以以相同的效率重复使用三个循环。最后,还研究了其他酮肟的反应。
Catalyst free synthesis of mono- and disubstituted pyrimidines from O-acyl oximes
catalyzed transformations of O-acyl oximes to various N-heterocycles are well established. Herein, we report a catalyst free, oxime carboxylate based, three-component condensation method to access mono- and disubstituted pyrimidines. A broad range of substituted pyrimidines were prepared in moderate to excellent yields. Control experiments reveal that in situ generated formamidine is the key intermediate.
Provided herein are novel and useful compounds having a tryptase inhibition activity, pharmaceutical compositions comprising such compounds, and methods treating subjects suffering from a condition, disease, or disorder that can be ameliorated by the administration of an inhibitor of tryptase, e.g., asthma and inflammatory diseases, to name only a few.