506423-20-7Relevant academic research and scientific papers
Enantioselective Synthesis of α-Chiral Propargylic Silanes by Copper-Catalyzed 1,4-Selective Addition of Silicon Nucleophiles to Enyne-Type α,β,γ,δ-Unsaturated Acceptors
Mao, Wenbin,Oestreich, Martin
supporting information, p. 8096 - 8100 (2020/11/02)
A copper-catalyzed deconjugative addition of silicon nucleophiles to a broad range of enyne-type α,β,γ,δ-unsaturated acceptors with high enantiocontrol is reported. The method is 1,4-selective with hardly any formation of the 1,6-adduct. The double-bond geometry is shown to be critical for achieving this chemoselectivity: exclusive 1,4-addition for E and predominant 1,6-addition for Z. By this, E-configured enynoates, enynamides, and enynones have been converted to the corresponding α-chiral propargylic silanes with excellent enantiomeric excesses.
PREPARATION AND UTILITY OF SUBSTITUTED ALLYLAMINES
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Page/Page column 62, (2008/12/06)
Disclosed herein are substituted allylamines having structural Formula I, processes of preparation thereof, pharmaceutical compositions thereof, and the methods of their use thereof. (I)
One-pot transformation of silyl enol ethers into 1,3-dienes: In situ generation of alkenyl nonaflates and subsequent Heck reactions - Scope and limitations
Lyapkalo, Ilya M.,Webel, Matthias,Reissig, Hans-Ulrich
, p. 3646 - 3658 (2007/10/03)
Palladium-catalysed reactions between methyl acrylate and the isolated alkenyl nonaflates 2a, 2d and 2e proceed without difficulties, furnishing the desired 1,3-dienes 3, 14 and 15 in good yields. The use of other alkenyl nonaflates and olefins in this Heck reaction was also examined. The main purpose of this study was the development of an in situ generation of the required alkenyl nonaflates 2 from the corresponding silyl enol ethers 1 and their one-pot transformation into 1,3-dienes. Thus, the previously described fluoride-promoted exchange of the trimethylsilyl substituent of typical enol ethers 1 for a nonafluorobutylsulfonyl group was directly combined with the palladium-catalysed coupling step. This sequence allowed the efficient transformation of a variety of silyl enol ethers 1 into highly substituted 1,3-dienes in a practical one-pot procedure. The scope and limitations, together with the chemo- and stereoselectivity, of this process are discussed. A particular intriguing example involves a one-pot synthesis of silyl enol ether 1j by means of a Diels-Alder reaction, subsequent nonaflation and a Heck reaction with tert-butyl acrylate, furnishing the highly functionalised 1,3-diene 30 in good overall yield. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
