39143-07-2Relevant articles and documents
Enantioselective Synthesis of Spiropyrazolone-Fused Cyclopenta[ c]chromen-4-ones Bearing Five Contiguous Stereocenters via (3+2) Cycloaddition
Khairnar, Pankaj V.,Su, Yin-Hsiang,Edukondalu, Athukuri,Lin, Wenwei
, p. 12326 - 12335 (2021/08/24)
An enantioselective synthesis of spiropyrazolone-fused cyclopenta[c]chromen-4-ones is demonstrated via a (3+2) cycloaddition reaction. The reactions of 3-homoacylcoumarins and α,β-unsaturated pyrazolones in the presence of the cinchona-alkaloid derived hy
A three-component, general and practical route for diastereoselective synthesis of aza-spirocyclic pyrazolonesviaa decarboxylative annulation process
Awasthi, Annapurna,Yadav, Pushpendra,Tiwari, Dharmendra Kumar
, p. 2374 - 2383 (2021/02/16)
An efficient, general, and practical route for highly diastereoselective synthesis of aza-spirocyclic pyrazolones from easily available α-amino acids, aldehydes, and alkylidene pyrazolones by means of a decarboxylative annulation process is reported. This
Enantio- and Diastereoselective Synthesis of β-Aryl-β-pyrazolyl α-Amino Acid Esters via Copper-Catalyzed Reaction of Azomethine Ylides with Benzylidenepyrazolones
Gong, Yan-Chuan,Wang, Yue,Li, Er-Qing,Cui, Hao,Duan, Zheng
supporting information, (2019/02/07)
A fully stereoselective synthesis of unnatural chiral β-aryl-β-pyrazolyl α-amino acid esters via copper-catalyzed addition reactions of azomethine ylides with benzylidenepyrazolones bearing two contiguous stereogenic centers was developed. A 1H-pyrazol-5-ol was introduced by the aromatization of 3H-pyrazol-3-one in the reaction. The transformation operated at room temperature and afforded β-1H-pyrazol-5-ol-α-amino esters in high yields with good to excellent levels of diastereo- and enantioselectivity.