Die Darstellung vonDL-1-Aryl-1-(2′-dimethylaminoäthyl-1′)-Δ2-cyclohexenen
作者:G. Schwenker、G. Metz
DOI:10.1002/ardp.19683010808
日期:——
1-Aryl-Δ1-cyclohexenole-(3) lassen sich mit Keten-O,N-acetal zu 1-Aryl-Δ2-cyclohexenyl-(1)-dimethylacetamiden umsetzen, deren Reduktion mit Lithiumalanat die Titelverbindungen ergibt. 1-Aryl-Δ1-cyclohexenols-(3) react with ketene-O,N-acetal to 1-aryl-Δ2-cyclohexenyl-(1)-dimethylacetamides, the reduction of which with LiAlH4 gives the compounds named in the heading.
Concise Total Syntheses of (±)-Joubertiamine, (±)-O-Methyljoubertiamine, (±)-3′-Methoxy-4′-O-methyljoubertiamine, (±)-Mesembrane, and (±)-Crinane
作者:Alakesh Bisai、Mrinal Das、Subhadip De
DOI:10.1055/s-0035-1561583
日期:——
Subsequent simple allylic oxidation of Eschenmoser–Claisen products and synthetic elaborations (reductions/oxidations) enabled the totalsyntheses of the title compounds to be completed in good yields in a few steps. The strategic viability was further tested in the totalsyntheses of Amaryllidaceae alkaloids (±)-mesembrane and (±)-crinane. Towards this end, we synthesized advanced intermediate keto-aldehydes
Concise total syntheses of (±)-mesembrane and (±)-crinane
作者:Mrinal Kanti Das、Subhadip De、Shubhashish Shubhashish、Alakesh Bisai
DOI:10.1039/c5ob00183h
日期:——
A unified approach to the Amaryllidaceae alkaloids having a cis-3a-aryloctahydroindole scaffold is developed via a key Eschenmoser–Claisen rearrangement of all-carbon quaternary stereocenters present in these alkaloids. Utilizing this strategy, a concise total synthesis of (±)-mesembrane and (±)-crinane is achieved.