Direct amino acid-catalyzed cascade biomimetic reductive alkylations: application to the asymmetric synthesis of Hajos–Parrish ketone analogues
作者:Dhevalapally B. Ramachary、Mamillapalli Kishor
DOI:10.1039/b807999d
日期:——
and enantioselective process for the double cascade synthesis of highly substituted 2-alkyl-cyclopentane-1,3-diones, 2-alkyl-3-methoxy-cyclopent-2-enones and Hajos-Parrish (H-P) ketone analogs is presented via reductive alkylation chemistry. For the first time, we have developed a single-step alkylation of cyclopentane-1,3-dione with aldehydes/ketones and a Hantzsch ester through an organocatalytic reductive
Cascade Oxypalladation/1,3-Palladium Shift to Access Cyclopentene-Fused Isocoumarins
作者:Vaibhav B. Patil、G. Raghu Ramudu、Rambabu Chegondi
DOI:10.1021/acs.orglett.4c01997
日期:2024.8.2
Fused isocoumarins are frequently found in several natural products and pharmaceuticals. Herein, a cascade annulation of 2-alkynylbenzoate-tethered cyclic 1,3-diones via sequential trans-oxypalladation, carbonyl insertion, 1,3-Pd shift, and β-hydride elimination is reported. This method provides efficient access to highly diastereoselective tetracyclic cyclopentene-fused isocoumarins containing two