作者:David R. Williams、Mark G. Fromhold、Jill D. Earley
DOI:10.1021/ol016336a
日期:2001.8.1
[structure: see text]. A stereocontrolled total synthesis of the polycyclic Stemona alkaloid, (-)-stemospironine (1) has been achieved. Key transformations include the use of a Staudinger reaction leading to the aza-Wittig ring closure of the perhydroazepine system. Formation of the vicinal pyrrolidine butyrolactone is described via the stereoselective intramolecular capture of an intermediate aziridinium
Stereospecific Synthesis of β<sup>3</sup>-Amino Acid Derivatives from Propargylic Alcohols: Efficient Solution-Phase Synthesis of Oligopeptides without Coupling Agents
A stereospecific synthesis of β3‐amino acids has been accomplished starting from readily available and enantioenriched propargylic alcohols. This conversion can be effected in only three steps by selenium‐mediated organic transformations of the carbon–carbon triple bond. This method is especially attractive because the reactive Se‐phenyl selenocarboxylate intermediates can be trapped with the amine
Synthesis of Fluorine-Containing Exoalkylidene β-Lactams
作者:Assaad Nasr El Dine、Danielle Grée、Thierry Roisnel、Elsa Caytan、Ali Hachem、René Grée
DOI:10.1002/ejoc.201501347
日期:2016.1
The Kinugasa reaction, applied to propargylic gem-difluorides, allows a very direct and efficient synthesis of new exoalkylideneβ-lactams with a fluorine in the vinylic position.
Enantioselective Addition of Activated Terminal Alkynes to 1-Acylpyridinium Salts Catalyzed by Cu−Bis(oxazoline) Complexes
作者:Zhankui Sun、Shouyun Yu、Zuoding Ding、Dawei Ma
DOI:10.1021/ja0734849
日期:2007.8.1
CuI/bis(oxazoline)-catalyzedaddition of propiolates and terminal ynones to 1-acylpyridinium salt (generated in situ from reaction of pyridine and methyl chloroformate) affords highly functionalized dihydropyridines with excellent enantioselectivity. It is found that the carbonyl group adjacent to the alkyne moiety is essential for the enantioselectivity of the addition. Short synthesis of indolizidines