Total Synthesis of (+)-Isoschizandrin Utilizing a Samarium(II) Iodide-Promoted 8-Endo Ketyl−Olefin Cyclization
作者:Gary A. Molander、Kelly M. George、Lauren G. Monovich
DOI:10.1021/jo0347361
日期:2003.12.1
The 13-step synthesis of (+)-isoschizandrin reported herein features a samarium(II) iodide-promoted 8-endo ketyl-olefin coupling to assemble the eight-membered ring present in the target concomitantly with the required functionality and stereochemistry. In constructing (+)-isoschizandrin as a single atropisomer, the synthesis utilizes a kinetic resolution of a seven-membered lactone using a CBS-oxazaborolidine
Enantioselective Syntheses of 2,5-Disubstituted Pyrrolidines Based on Iridium-Catalyzed Allylic Aminations-Total Syntheses of Alkaloids from Amphibian Skins
作者:Martin Gärtner、Robert Weihofen、Günter Helmchen
DOI:10.1002/chem.201100649
日期:2011.6.27
A broadly applicable route to trans‐2,5‐disubstituted pyrrolidines has been developed. Key steps are an asymmetric iridium‐catalyzed allylic amination, a Suzuki–Miyaura coupling, and an intramolecular aza‐Michael addition. Enantiomeric excesses in the range of 93–99 % ee have been achieved. Total syntheses of the alkaloids (−)‐225 C, (+)‐ and (−)‐223 H (xenovenine), (+)‐223 AB, (+)‐195 B, and (+)‐223 R
Synthetic studies on clerodane diterpenoids. 4. The total synthesis of (±)-6β-acetoxy-2-oxokolavenool
作者:Hsing-Jang Liu、Kak-Shan Shia
DOI:10.1016/s0040-4020(98)00828-x
日期:1998.10
The first totalsynthesis of the title compound in racemic form has been accomplished from ketone 4, a readily accessible compound via an intermolecular Diels-Alder approach developed previously for the synthesis of clerodane diterpenoids.