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Three-in-one: A short synthetic route readily gives access to a new class of chiral (P,N) ligands characterized by three distinct elements of chirality. These ligands are highly enantioselective in the challenging Pd-catalyzed intramolecular asymmetric α-arylation of α-branched aldehydes (see picture).

We disclose herein a highly enantioselective de novo-synthesis of chiral 1-cyclopentenyl-α-keto esters starting from a simple bis-silyl-1,3-dienediolate and α,β-unsaturated aldehydes via a domino vinylogous Michael-intramolecular Knoevenagel-type condensation. The cyclopentenes proved to be highly versatile and were readily converted into various structural motifs.

The selective α-arylation and α-arylative esterification of linear and branched aldehydes is reported for a variety of bromoarenes. The acylation of aryl bromides can be achieved with linear aldehydes (see scheme). All these transformations were performed with a single [(N-heterocyclic carbene)Pd] catalyst through adjustment of the stoichiometry of the reagents and the appropriate base.

Three-in-one: A short synthetic route readily gives access to a new class of chiral (P,N) ligands characterized by three distinct elements of chirality. These ligands are highly enantioselective in the challenging Pd-catalyzed intramolecular asymmetric α-arylation of α-branched aldehydes (see picture).

A variety of aromatic and aliphatic nitroalkenes or nitrodienes undergoes heterocoupling reaction with methyl vinyl ketone (II) or acrylate (IV) in the presence of LiCl and imidazole.