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A multicomponent strategy was applied to the synthesis of chiral bidentate unsaturated hydroxyalkyl- and carboxyalkyl-N-heterocyclic carbene (NHC) precursors. The newly developed low-cost chiral ligands derived from amino alcohols and amino acids were evaluated in copper-catalyzed asymmetric conjugated addition and asymmetric allylic alkylation, which afforded the desired tertiary and quaternary carbon stereocenters with excellent regio- and enantioselectivities (up to 99:1 e.r.).

Bifunctional ligands: A multicomponent strategy was applied to the synthesis of chiral bidentate unsaturated hydroxyalkyl- and carboxyalkyl-N-heterocyclic carbene (NHC) precursors. The newly developed low-cost chiral bifunctional ligands were evaluated in copper-catalyzed asymmetric conjugated addition (ACA) and asymmetric allylic alkylation (AAA; see scheme).

The aniline carbamate is introduced as a new removable directing group for CH activation. Its versatility and ability as a directing group are demonstrated by its use in the ortho-arylation of a wide variety of aniline derivatives under palladium(II) catalysis, with symmetric diaryliodonium salts as aryl donors. The reaction differs from previously reported arylations in its selectivity and its mechanism, as elucidated by kinetic and isotopic experiments. The directing group can also be easily removed under a variety of conditions.

G′day, (carba)mate! A new removable directing group for sp² CH activation, the aniline carbamate, is examined in detail. Its utility as a directing group is demonstrated by the ortho-arylation of aniline derivatives under Pd^II catalysis, with iodonium salts as aryl donors and oxidants. Excellent regio- and chemoselectivity were observed. The directing group can also be easily removed to yield 2-aminobiaryl products (see scheme).