Nickel(0)-catalyzed disilylative and silastannylative cyclizations of 1,3-diene and tethered aldehyde

Nickel(0)-catalyzed bismetallative cyclization of 1,3-diene and a tethered aldehyde in the presence of PhF₂SiSiMe₃ or Me₃SiSnBu₃ gave the corresponding cyclized product having an allylsilyl or an allylstannyl unit in the side chain in good yields. The cyclized product obtained from the reaction in the presence of Me₃SiSnBu₃ had reactivity as an allylstannane derivative, and the coupling reaction with benzaldehyde proceeded in a diastereoselective manner. When the silastannylative cyclization was carried out in the presence of a chiral monodentate phosphine ligand, the cyclized product was produced as an optically active form with modest enantiomeric excess.