[reaction: see text] Enantioselective Ir-catalyzed intramolecular allylic aminations and etherifications are described. Up to 97% ee was achieved using catalysts prepared by in situ activation of mixtures of phosphorus amidites and [Ir(COD)Cl]2. Sequential aminations of bis-allylic carbonates, involving an inter- followed by an intramolecular reaction, gave trans-N-benzyl-2,5-divinylpyrrolidine and trans-N-benzyl-2,6-divinylpiperidine with > or = 99% ee. New phosphorus amidites as well as improved conditions for intermolecular aminations are reported.
We disclose in this study a Ni
6
AlO
x
catalyst prepared by coprecipitation
for the reductive amination
of biomass-derived aldehydes and ketones in aqueous ammonia under
mild reaction conditions. The catalyst exhibited 99% yield toward
5-aminomethyl-2-furylmethanol in the reaction of 5-hydroxymethyl furfural
with ammonia at 100 °C for 6 h under 1 bar H
2
. The
catalyst was further extended to the reductive amination of a library
of aromatic and aliphatic aldehydes and ketones with a yield in the
range 81–90% at optimized reaction conditions. Besides, 5-hydroxymethylfurfural
could react with a library of primary and secondary amines with yields
in the range 76–88%. The catalyst could be easily recycled
and reused without apparent loss of activity in four consecutive runs.
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