we achieved an efficient and sustainable synthesis of secondary amine hydrochlorides via a fully continuous flow; in the second step, we developed a Pictet–Spengler reaction/Friedel–Crafts hydroxyalkylation/dehydration cascade for the construction of the dihydroprotoberberine core structure (ABCD-ring); and in the last step, Ir-catalyzed enantioselective hydrogenation was employed for the introduction
Hofmann degradation of .beta.-hydroxy ammonium salts. .alpha.- and .beta.-Hydroxylaudanosine, 7-hydroxyglaucine, and 13-hydroxyxylopinine
作者:Kathleen L. Wert、Samuel Chackalamannil、Eric Miller、David R. Dalton、David E. Zacharias、Jenny P. Glusker
DOI:10.1021/jo00147a020
日期:1982.12
A General, Concise Strategy that Enables Collective Total Syntheses of over 50 Protoberberine and Five Aporhoeadane Alkaloids within Four to Eight Steps
作者:Shiqiang Zhou、Rongbiao Tong
DOI:10.1002/chem.201601245
日期:2016.5.17
reported. This synthesis represents the most efficient and shortest route to date, featuring three catalytic processes: CuI‐catalyzed redox‐A3 reaction, Pd‐catalyzed reductive carbocyclization, and PtO2‐catalyzed hydrogenation. Importantly, this new strategy to the tetracyclic framework has also been applied to the collective concise syntheses of >30 natural protoberberines (without 13‐methyl group) and