4176-69-6Relevant articles and documents
Which Factors Control the Nucleophilic Reactivities of Enamines?
Timofeeva, Daria S.,Mayer, Robert J.,Mayer, Peter,Ofial, Armin R.,Mayr, Herbert
, p. 5901 - 5910 (2018)
Changes in rate constants, equivalent to changes in Gibbs energies of activation ΔG≠, are commonly referred to as kinetic effects and differentiated from thermodynamic effects (ΔrG°). Often, little attention is paid to the fact that structural effects on ΔG≠ are composed of a thermodynamic (ΔrG°) and a truly kinetic (intrinsic) component (ΔG0≠), as expressed by the Marcus equation. Rate and equilibrium constants have been determined for a number of reactions of enamines with benzhydrylium ions (Aryl2CH+), which has allowed the determination of Marcus intrinsic barriers and a differentiated analysis of structure–reactivity relationships. To our knowledge, this is the first report in which the Lewis basicity of a πCC bond towards carbon-centered Lewis acids (for example, carbenium ions) has quantitatively been determined. The synthesis, structures, and properties of deoxybenzoin-derived enamines ArCH=C(Ph)NR2, which have been designed as reference nucleophiles for the future quantification of electrophilic reactivities, are explicitly described.
Stereo- and regioselective gold-catalyzed hydroamination of internal alkynes with dialkylamines
Hesp, Kevin D.,Stradiotto, Mark
supporting information; experimental part, p. 18026 - 18029 (2011/03/16)
We report the use of a P,N-ligand to support a gold complex as a state-of-the-art precatalyst for the stereoselective hydroamination of internal aryl alkynes with dialkylamines to afford E-enamine products. Substrates featuring a diverse range of functional groups on both the amine (ether, sulfide, N-Boc amine, fluoro, nitrile, nitro, alcohol, N-heterocycles, amide, ester, and carboxylic acid) and alkyne (ether, N-heterocycles, N-phthalimide amines, and silyl ethers) are accommodated with synthetically useful regioselectivity.
Studies on dioxirane chemoselectivity: The oxidation of an enamino moiety present in a Fischer carbene complex
Lluch, Anna-Maria,Gibert, Mariona,Sanchez-Baeza, Francisco,Messeguer, Angel
, p. 3973 - 3982 (2007/10/03)
The dimethyldioxirane (DMD) promoted oxidative decomplexation of Fischer carbene complex 1, which contains a conjugated enamino moiety, was investigted. Thus, treatment of 1 with 3 molecular equivalents of DMD afforded a 52% yield of amide 3 as unique isolable organic product. When the reaction was performed with 1 molecular equivalent of DMD the formation of the enol intermediate 15 was evidenced by its capture as the tetrafluoroboric acid salt 16. This salt was unstable and when it was exposed to air gave rise to amide 3 and to low amounts of ethyl benzoate and acetophenone. These results indicate that the presence of an enamino group conjugated to the Fischer carbene moiety inverts the chemoselectivity previously observed in the DMD promoted decomplexation of these compounds. Thus, the major pathway involves the oxidation of the enamino double bond through the formation of an enol intermediate which reacts with oxygen to give products resulting from the breakdown of the molecule.
