Lanthanide replacement in organic synthesis: Luche-type reduction of α,β-unsaturated ketones in the presence of calcium triflate
作者:Nina V. Forkel、David A. Henderson、Matthew J. Fuchter
DOI:10.1039/c2gc35619h
日期:——
calcium-mediated regioselective 1,2-reduction of challenging α,β-unsaturated ketones, such as 2-cyclopententone, is reported. The corresponding allylic alcohols are obtained in very good regioselectivities using Ca(OTf)2 and NaBH4. Furthermore, we have shown that our method can stereoselectively reduce aziridinyl ketones.
The first asymmetric Cu-catalyzed conjugate addition of dialkylzinc zinc reagents to a large scope of enals in presence of phosphoramidite, SimplePhos, or (R)-BINAP ligands with enantiomeric excesses up to 90% is reported. Moreover, ACA of Grignard reagents afforded moderate to good 1,4-regioselectivities with enantioselectivities up to 90%.
materials. Herein we disclose a catalyst‐ and reagent‐free formal aza‐Wacker type cyclization reaction for the synthesis of functionalized saturated N‐heterocycles. Key to the success is to conduct the reactions in a continuous‐flow electrochemical reactor without adding supporting electrolyte or additives. The reactions are characterized by broad tolerance of di‐, tri‐ and tetrasubstituted alkenes.
Disclosed are a catalyst including a hydrotalcite and, immobilized on a surface thereof, particles of at least one metal selected from the group consisting of Cu, Ag, and Au; a method for producing a carbonyl compound through dehydrogenation of an alcohol in the presence of the catalyst; and a method for producing a carbonyl compound through dehydrogenation of an alcohol in the presence of a catalyst including a hydrotalcite and, immobilized on a surface thereof, particles of a metal, in which dehydrogenation is performed in the absence of oxygen.
Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study
作者:Graeme Barker、David G. Johnson、Paul C. Young、Stuart A. Macgregor、Ai-Lan Lee
DOI:10.1002/chem.201501607
日期:2015.9.21
necessary to ensure efficient and general chirality transfer. Computationalstudies suggest that the efficiency of chirality transfer is linked to the aggregation of the alcohol nucleophile around the reactive π‐bound Au–allylic ether complex. With a single alcohol nucleophile, a high degree of chirality transfer is predicted. However, if three alcohols are present, alternative proton transfer chain mechanisms