Catalytic Asymmetric Synthesis of Chiral Allylic Amines. Evaluation of Ferrocenyloxazoline Palladacycle Catalysts and Imidate Motifs

Palladium(II) catalysts based on a ferrocenyloxazoline palladacyclic (FOP) scaffold were synthesized
and evaluated for the rearrangement of prochiral allylic N-(4-methoxyphenyl)benzimidates. When
iodide-bridged dimer FOP precatalysts are activated by reaction with excess silver trifluoroacetate,
the allylic rearrangement of both E and Z prochiral primary allylic N-(4-methoxyphenyl)benzimidates takes place at room temperature to give the corresponding chiral allylic N-(4-methoxyphenyl)benzamides in high yield and good ee (typically 81−95%). Several allylic imidate
motifs were evaluated also. Because the corresponding enantioenriched allylic amide products can
be deprotected in good yield to give enantioenriched allylic amines, allylic N-aryltrifluoroacetimidates
were identified as promising substrates.