Subscribe to RSS
DOI: 10.1055/s-1999-3106
Iridium Ferrocenyl Diphosphine Catalyzed Enantioselective Reductive Alkylation of a Hindered Aniline
Publication History
Publication Date:
31 December 1999 (online)
The enantioselective reductive alkylation of 2-methyl-5-ethyl-aniline (MEA) with methoxyacetone - using a catalyst generated in situ from [Ir(cod)Cl]2 and (R)-(S)-PPF-P(3,5-xyl)2 - to give enriched (S)-N-(2-ethyl-6-methylphenyl)-N-(1′-methoxymethyl)-ethyl-amine is described. At 80 bar and 50 °C in the presence of iodide and methane sulfonic acid and with cyclohexane as solvent, complete conversion is reached within 14 h with a substrate to catalyst ratio of 10'000 and an ee of 76-78%. The effect of solvent and acid type were found to be important. To our knowledge, this is the first enantioselective reductive alkylation ever reported.
enantioselective reductive alkylation - hindered N-alkyl aniline - Ir-ferrocenyl diphosphine - acid catalysis - (S)-metolachlor