Halide-bridged palladium(II) dimers of orthometalated (S)-(+)-N,N-dimethyl-alpha-methylbenzylamine and (S)-(+)-N,N-dimethyl[1-(2-naphthyl)ethyl]amine: Solution and solid-state structures and reactions with 3,4-dimethyl-1-phenylphosphole and allyldiphenylphosphine

Activation thermodynamics for the cis reversible arrow trans isomerization of the chloride-, bromide-, and iodide-bridged palladium(II) dimers of orth ometalated (S)-(+)-N,N-dimethyl-alpha-methylbenzylamine (TMBA) and (S)-(+)- N,N-dimethyl[1-(2-naphthyl)-ethyl]amine (TMNA) have been determined by vari able-temperature H-1 NMR spectroscopy. The chloride-bridged dimers are clea ved regioselectively by 3,4-dimethyl-1-phenylphosphole (DMPP) and allyldiph enylphosphine (ADPP) to form the mononuclear products {Pd(C6H4CH(Me)NMe2(R3 P)Cl} and {Pd(C10H6CH(Me)NMe2(R3P)Cl} (R3P = DMPP, ADPP), with the phosphin e exclusively trans to nitrogen. The chloride-bridged dimers react with NaP F6 or AgClO4, DMPP, and CH3CN to produce {Pd(C6H4CH(Me)NMe2(DMPP)(CH3CN)}X and {Pd(C10H6CH(Me)NMe2(DMPP)(CH3CN)}X (X = PF6-, ClO4-). They react with N aPF6 or AgClO4 and excess DMPP to form [Pd(DMPP)(4)](X)(2) (X = PF6-, ClO4- ). When X = PF6-, this complex undergoes two thermal [2+2] dimerizations of the coordinated DMPP ligands in the solid state to form {Pd(DMPP2-[2+2])(2 )}(PF6)(2). The complex {Pd(C10H6CH(Me)NMe2(DMPP)Cl} reacts with AgClO4 and ADPP at 75 degrees C to form an unusual chloride-bridged tetrapalladium(II ) macrocycle that contains a novel tridentate ligand with bridging phosphid e and terminal R3P and C(-) donors. New complexes were characterized by ele mental analyses, physical properties, infrared spectroscopy, polarimetry, a nd H-1, H-1{P-31}, C-13{H-1}, and P-31{H-1} NMR spectroscopy and in most ca ses by X-ray crystallography.