Development of a Strategy for Linear-Selective Cu-Catalyzed Reductive Coupling of Ketones and Allenes for the Synthesis of Chiral γ-Hydroxyaldehyde Equivalents
作者:Raphael K. Klake、Samantha L. Gargaro、Skyler L. Gentry、Sharon O. Elele、Joshua D. Sieber
DOI:10.1021/acs.orglett.9b02973
日期:2019.10.4
N-substituted allyl equivalents generated from a chiral allenamide. By choice of the appropriate ligand for the Cu-catalyst, high linear selectivity can be obtained with good diastereocontrol. This methodology allows access to chiral γ-hydroxyaldehyde equivalents that were applied in the synthesis of chiral γ-lactones and 2,5-disubstitued tetrahydrofurans.
Access to Chiral Diamine Derivatives through Stereoselective Cu-Catalyzed Reductive Coupling of Imines and Allenamides
作者:Toolika Agrawal、Robert T. Martin、Stephen Collins、Zachary Wilhelm、Mytia D. Edwards、Osvaldo Gutierrez、Joshua D. Sieber
DOI:10.1021/acs.joc.0c02971
日期:2021.4.2
inducers in stereoselective synthesis that are challenging to prepare in a straightforward and stereoselective manner. Herein, we disclose a cost-effective and readily available Cu-catalyzed system for the reductive coupling of a chiral allenamide with N-alkyl substituted aldimines to access chiral 1,2-diamino synthons as single stereoisomers in high yields. The method shows broad reaction scope and
Cross‐Coupling of Allenamides and
<i>C</i>
‐Based Nucleophiles by Pd‐Catalyzed Allylic Alkylation
作者:Joshua D. Sieber、Raphael K. Klake、Toolika Agrawal、Dang Binh Ho、Samantha L. Gargaro、Stephen Collins、Mytia D. Edwards
DOI:10.1002/ijch.202000096
日期:2021.5
Pd-catalyzedallylicalkylation of C-based nucleophiles using both chiral and achiral allenamides is described. High yields were obtained to provide synthetically valuable (E)-enamide products in high E : Z-selectivity while generating a quaternary carbon atom. Some potential stereocontrolled applications of the resultant (E)-enamide functionality are described.
描述了使用手性和非手性丙二烯酰胺对C基亲核试剂进行Pd 催化的烯丙基烷基化。获得高产率以提供具有高E:Z选择性的具有合成价值的 ( E )-烯酰胺产品,同时生成季碳原子。描述了所得 ( E )-烯酰胺官能团的一些潜在立体控制应用。
Copper‐Catalyzed Synthesis of Terminal vs. Fluorine‐Substituted
<i>N</i>
‐Allenamides via Addition of Diazo Compounds to Terminal Ynamides
diazo-compounds was developed. DFT calculations showed that this transformation relies on an uncommon, reversed mechanism that, regardless of the polarization of the ynamide, favors the addition of the diazo compound at the β-position of the ynamide. The protocol tolerates a wide range of functional groups. This copper-catalyzed process represents the first synthesis of tri-, di- or per-fluorinated N-allenamides
Synthesis of amido-spiro[2.2]pentanes via Simmons–Smith cyclopropanation of allenamides
作者:Ting Lu、Ryuji Hayashi、Richard P. Hsung、Kyle A. DeKorver、Andrew G. Lohse、Zhenlei Song、Yu Tang
DOI:10.1039/b908205k
日期:——
Simmons–Smith cyclopropanations of allenamides en route to amido-spiro[2.2]pentanes is described here. While the diastereoselectivity was low when using unsubstituted allenamides, the reaction is overall efficient and general, representing the most direct synthesis of both chemically and biologically interesting amido-spiro[2.2]pentane systems. With α-substituted allenamides, while the diastereoselectivity