Pd-Catalyzed Asymmetric Allylic Alkylation of Pyrazol-5-ones with Allylic Alcohols: The Role of the Chiral Phosphoric Acid in C–O Bond Cleavage and Stereocontrol
作者:Zhong-Lin Tao、Wen-Quan Zhang、Dian-Feng Chen、Arafate Adele、Liu-Zhu Gong
DOI:10.1021/ja402740q
日期:2013.6.26
The combination of a palladium complex with a chiral phosphoramidite ligand and a chiral phosphoric acid enables the first highly efficient asymmetricallylic alkylation of pyrazol-5-ones with allylicalcohols, affording multiply functionalized heterocyclic products in high yields with excellent enantioselectivities that would be of great potential in the synthesis of pharmaceutically interesting molecules
Design, Synthesis, and Structure‐Activity Relationship Study of Pyrazolones as Potent Inhibitors of Pancreatic Lipase
作者:Jing Zhang、Yang Yang、Xing‐Kai Qian、Pei‐Fang Song、Yi‐Shu Zhao、Xiao‐Qing Guan、Li‐Wei Zou、Xiaoze Bao、Hong Wang
DOI:10.1002/cmdc.202000850
日期:2021.5.18
mixed-competitive inhibitor of PL (IC50=0.30 μM). In addition, P32 displayed some selectivity over other known serine hydrolases. A molecular docking study for P32 demonstrated that the inhibitoryactivity of P32 towards PL could be attributed to the π-π interactions of 2-naphthyl unit (R1) and hydrophobic interactions of phenylmoiety (R3) with the active site of PL. Thus, P32 could serve as promising lead
Highly selective: The title reaction is achieved with high enantiomeric and geometric control and thermodynamically unstable (Z)‐enone derivatives are obtained as the major products (see scheme). The procedure tolerates a wide range of substrates to generate optically active pyrazolones with vinyl‐substituted quaternary stereocenters.
Asymmetric α-Amination of 4-Substituted Pyrazolones Catalyzed by a Chiral Gd(OTf)<sub>3</sub>/<i>N,N′</i>-Dioxide Complex: Highly Enantioselective Synthesis of 4-Amino-5-pyrazolone Derivatives
The asymmetric α-amination of 4-substituted pyrazolones with azodicarboxylates was investigated for the first time, employing an N,N′-dioxide gadolinium(III) complex as the catalyst. The novel transformations exhibited high yield, and 4-amino-5-pyrazolone derivatives bearing a chiral quaternary center were obtained in excellent yields (up to 99%) and enantioselectivities (90%−97% ee) for a broad scope
An asymmetric method for the amination of pyrazol‐5‐ones using azo compounds is described. The developed process exhibits a wide substrate scope and high efficiency in terms of yield and enantioselectivity.