α‐carbonyl homoallylic alcohols have been synthesized in a one‐pot reaction from benzaldehyde and allylic alcohols. The nickel‐catalyzed allylation of α‐hydroxyketones has first been studied and allowed the identification of Ni(cod)2/dppf as the most suitable catalytic system. The tandem reaction that combines the benzoin condensation of aldehydes (synthesis of α‐hydroxyketones) promoted by the 1,3‐dimethylimidazolium chloride/DBU system and the nickel‐catalyzed allylic alkylation with allylic alcohol has been realized in EtOH as green solvent. The reaction is 100 % atom‐economical and water is formed as sole by‐product. A broad scope of different benzaldehyde derivatives as well as various allylic alcohols is also described.

Synthesis and crystal structures of palladium complexes based on α-amino-oximes derived from (R)-limonene and their application in allylic alkylation of 1,3-dioxo compounds

A dinuclear nickel complex with (S)-limonene based aminooxime ligand has been isolated and its crystal structure determined. The resolved structure of dichloridobis{(2S,5R)-2-methyl-5-(prop-1-en-2-yl)-2-[(pyridin-2-yl)methylamino]cyclohexan-1-one oxime}dinickel(II), [Ni2Cl2(C16H23ClN3O)2], at 100 K has monoclinic (P21) symmetry. The two NiII ions in the dinuclear complex are each coordinated in a distorted octahedral environment by three nitrogen atoms, a terminal chloride and two μ bridging chlorides. Each oxime ligand is coordinated to nickel(II) by the three nitrogen atoms, leading to two five-membered chelate rings, each displaying an envelope conformation. In the crystal, numerous intermolecular and intramolecular hydrogen bonds lead to the formation of a three-dimensional network structure.