Palladium(II) and platinum(II) complexes with 1,4,8,11-tetramethyl-1,4,8,11-tetraphosphacyclotetradecane were prepared by a template reaction in which [M(MeHPCH2CH2PHMe)2]Cl2 (M = Pd, Pt) reacts with 1,3-dibromopropane in the presence of K2HPO4 as a base. The bromide salts of the Pd2+(6a) and Pt2+(6b) complexes were isolated as crystals in a low yield. Their molecular structures were determined by X-ray crystallography. Both compounds have a square-planar geometry in which the configurations of the four asymmetric phosphorus atoms are of the trans III (RRSS) type. The M−P bond distances for 6a and 6b are 2.268(1) and 2.277(2) Å, respectively, which are slightly smaller than those of the complexes with noncyclic phosphines. Crystallographic data for 6a:  monoclinic, space group C2/m, a = 8.4856(7) Å, b = 17.273(1) Å, c = 9.5712(7) Å, β = 101.117(7)°, V = 1376.5(2) Å3, Z = 2, and R = 0.042. Crystallographic data for 6b:  triclinic, space group P1̄, a = 9.538(3) Å, b = 9.781(2) Å, c = 8.719(1) Å, α = 115.34(2)°, β = 92.92(2)°, γ = 61.33(2)°, V = 632.6(3) Å3, Z = 1, and R = 0.041.

Divinylketone and the trimethylsilyl enol ethers of cyclohex-2-en-I -ones undergo Lewis acid assisted triple Michael reactions yielding tricyclo[5.3.1.03~*]undecan-4,11 -diones; the application of this reaction enabled a formal synthesis of (+)-seychellene (5).

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Acrylates having a chiral auxiliary react with the trimethylsilyl enol ether of 1-acetylcyclohexene in the presence of Et2AlCl to give 4-substituted 1-decalones with 0–70% diastereoselectivity. The absolute stereostructure of the decalones have been determined by applying the exciton chirality method to the dibenzoate derivative.