Rhodium-Catalyzed Enantioselective Addition of Organoaluminum Reagents to<i>N</i>-Tosyl Ketimines
作者:Sebastian Hirner、Andreas Kolb、Johannes Westmeier、Sandra Gebhardt、Stephen Middel、Klaus Harms、Paultheo von Zezschwitz
DOI:10.1021/ol501372u
日期:2014.6.6
Rhodium(I)/Binap complexescatalyzehighlyenantioselective additions of methyl- and arylaluminum reagents to cyclic α,β-unsaturated N-tosyl ketimines. Depending on the solvent and substituents at the ring, the reaction occurs either in a 1,2-manner to deliver α-tertiary allylic amines or in a 1,4-manner to yield, after subsequent reduction, 3-substituted cycloalkyl amines. Well known in the case of
Enantioselective Preparation of 3-Arylcycloalkylamines by Rhodium-Catalyzed 1,4-Addition and Subsequent Stereodivergent Reduction
作者:Sandra Gebhardt、Christian H. Müller、Johannes Westmeier、Klaus Harms、Paultheo von Zezschwitz
DOI:10.1002/adsc.201400824
日期:2015.2.9
AbstractN‐Sulfonylimines of cycloalk‐2‐enones are well‐suited for the enantioselective rhodium(I)/binap‐catalyzed 1,4‐additions of arylzinc halides. The cyclic enamides, obtained after quenching, are sensitive towards chromatography, but can undergo diastereoselective reductions to furnish cis‐ or trans‐3‐arylcycloalkylamines with five‐ to seven‐membered rings. The 1,4‐addition is not influenced by a methyl group at C‐5 of six‐membered rings, providing further configurational options. 3‐Arylcycloalkylamines are subunits in a number of bioactive substances and can also be oxidatively transformed into cyclic γ‐amino acids.magnified image