Chiral Bifunctional Ferrocenylphosphine‐Catalyzed Enantioselective Allylic Alkylation of Morita−Baylis−Hillman Carbonates with Pyrazolin‐5‐ones

Recent advances in the applications of pyrazolone derivatives in enantioselective synthesis

Pyrazolones and pyrazoles, featuring nitrogen-nitrogen bonds, are two of the most important classes of heterocycles, owing to their widespread occurrence in medicinal chemistry and functional materials. The last decade has witnessed a rapid increase in the construction of chiral pyrazolone and pyrazole derivatives, with the application of pyrazolone derivatives as powerful synthons. Since our last review in 2018, a large number of new achievements has emerged in this area, requiring a timely update. Thus, this review summarizes these elegant achievements based on the multiple reactive sites of different pyrazolone synthons. In addition, important mechanisms and interesting biological investigations relating to the corresponding products are also discussed.

Enantioselective synthesis of functionalized 1,4-dihydropyrazolo-[4',3':5,6]pyrano[2,3-b]quinolines through ferrocenyl-phosphine-catalyzed annulation of modified MBH carbonates and pyrazolones

An enantioselective synthesis of highly functionalized 1,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-b]quinolines from modified MBH carbonates and pyrazolones via a chiral phosphine-mediated alkylation/annulation sequence has been realized. The chiral dihydropyrano[2,3-c]pyrazoles bearing bio-active condensed heterocycles were facilely formed in good chemical yields and with high to excellent enantioselectivity by utilizing low catalyst loading.

Construction of spirooxindole-fused spiropyrazolones containing contiguous three stereogenic centres via [3 + 2] annulation utilizing a ferrocene derived bifunctional phosphine catalyst

Regional and stereoselective construction of spirooxindole-fused spiropyrazolones containing contiguous three stereogenic centres via [3 + 2] annulation catalyzed by ferrocene derived bifunctional phosphine.

Recent developments in the synthesis and applications of chiral ferrocene ligands and organocatalysts in asymmetric catalysis

This review highlights recent advances in the synthesis and application of ferrocene-containing chiral ligands and organocatalysts in asymmetric catalysis.