Experimental and theoretical mechanistic studies on the Cu(OTf)2-catalyzed hydroamination reaction of terminal allenes with secondary amines reveal that in situ generated cationic Cu(I) is the catalytically active species and explain the observed regio- and stereoselectivity for the unbranched E product. Insight into the structure of the relevant transition states allowed the generalization of this
Pauson–Khand reactions of functionalized allenes with different alkynes give cyclopentenones with generally high regio- and stereoselectivities. The allenes react through their external double bonds, giving cyclopentenones with exocyclic double bond at their β positions and predominantly with E stereochemistry. Some intramolecularreactions with allenynes connected through aromatic rings are described
具有不同炔烃的官能化丙二烯的 Pauson-Khand 反应产生具有通常高区域选择性和立体选择性的环戊烯酮。丙二烯通过它们的外部双键反应,得到在其 β 位置具有环外双键的环戊烯酮,主要是 E 立体化学。描述了通过芳环连接的丙炔的一些分子内反应。这些以中等至良好的产率得到相应的杂环。
New regio and stereoselective intermolecular Pauson–Khand reactions of allenamides
IntermolecularPauson–Khandreactions are still quite limited in scope and yields. There are also few reports using allenes as the olefinic part in this version. We report herein new regio and stereoselective reactions of allenamides with several alkynes. These reactions give functionalized cyclopentenones bearing an exocyclic enamide, which can be useful synthetic intermediates.
An atom-economic method of preparing allylic sulfones via hydrosulfonylation of allenes with sulfinic acids under Pd(0)-catalysis was reported. This process has a high degree of regio- and stereoselectivity, and provides the target product with a moderate to excellent yield. A wide range of nitrogen- or oxygen-containing linear E-allylic sulfones have been synthesized. With the support of experimental
Photocatalytic selective synthesis of (<i>E</i>)-β-aminovinyl sulfones and (<i>E</i>)-β-amidovinyl sulfones using Ru(bpy)<sub>3</sub>Cl<sub>2</sub> as the catalyst
Selectively producing a variety of valuable compounds using controlled chemical reactions starting from a common material is an appealing yet complex concept. Herein, a photocatalytic approach for the selective synthesis of (E)-β-aminovinyl sulfones and (E)-β-amidovinyl sulfones from allenamides and sodium sulfinates was established. This reaction exhibits the traits of an eco-friendly solvent and