Oxidative addition of azide anion to triisopropylsilyl enol ethers: Synthesis of α-azido ketones and 2-amino(methoxycarbonyl)alk-2-en-1-ones
摘要:
Treatment of triisopropylsilyl enol ethers with eerie ammonium nitrate/sodium azide at -20 degrees C in acetonitrile gives alpha-azido ketones in average to good yields (50-80%). Subsequent conversion of the alpha-azido ketones into 2-amino(methoxycarbonyl)cycloalk-2-en-1-ones is described.
Catalytic [3+2] Annulation of Aminocyclopropanes for the Enantiospecific Synthesis of Cyclopentylamines
作者:Florian de Nanteuil、Jérôme Waser
DOI:10.1002/anie.201106255
日期:2011.12.9
With nitrogen too: The first catalytic [3+2] annulation of aminocyclopropanes with enol ethers is reported (see scheme; Phth=phthaloyl). The reaction worked with easily accessible phthalimidocyclopropanes using 5 mol % of SnCl4 in nearly quantitative yields. Polysubstituted cyclopentylamines, which are often present in bioactive compounds, were obtained with high diastereoselectivity and enantiospecificity
Rapid assembly of stereochemically rich polycyclic tetrahydrofurans by a conjugate addition-Rh(II) catalysis sequence
作者:Evan M. Howard、Avery M. Peck、Isabelle E. Petrucci、Matthias Brewer
DOI:10.1016/j.tetlet.2022.154137
日期:2022.10
efficient reaction sequence that gives stereochemically rich, polycyclic tetrahydrofurans is described. A highly diastereoselective conjugate addition of enoxy silanes to vinyl diazonium salts gives 2-diazo-1,5‑dicarbonylcompounds in yields up to 99%. The diazo functional group can then be taken advantage of in subsequent Rh catalyzed carbonyl ylide 1,3-dipolar cycloaddition or OH insertion reactions to
N-(Trimethylsilyl)formaldimine-AlCl3 complex 2b was generated by treating (trimethylsilyl)methyl azide with AlCl3. The reaction of 2b with various kinds of enol triisopropylsilyl ethers afforded alpha'-aminomethylated enol silyl ethers in good yields.
A Novel [5+2] Cycloaddition Reaction Using a Dicobalt Acetylene Complex