723281-06-9Relevant academic research and scientific papers
[(Piperidinomethyl)silylmethyl] cyclopalladated complexes: Their synthesis, reactivity, and solid state structures
Schildbach, Daniel,Arroyo, Marta,Lehmen, Klaus,Martin-Barrios, Susana,Sierra, Luisa,Villafane, Fernando,Strohmann, Carsten
, p. 3228 - 3238 (2004)
The reaction of Ph2Si(CH2Li)(CH2NC 5H10) (2) (CH2NC5H10 = piperidinomethyl) with trans-[PdCl2(SMe2)2] leads to dimeric [Pd{CH2SiPh2(CH2NC 5H10)-κ2C,N}(μ-Cl)]2 (3), where the [CH2-SiPh2(CH2NC5H 10)-κ2C,N] ligand forms a palladacycle, as revealed by the crystal structure of the transoid isomer. In solution, this chloro-bridged dimer exists as a mixture of the cisoid and the transoid isomer. Monodentate ligands cleave the chloro bridges of dimer 3 to give compounds of the type [Pd{CH2SiPh2(CH2NC5H 10)-κ2C,N}ClL] [L = PPh3 (4), PMe 3 (5), CNiBu (6), 4-methylpyridine (4-MePy) (7), tetrahydrothiophene (tht) (8), SMe2 (9)], where the incoming ligand and the metalated carbon center are coordinated cis. The tetrafluoroborate salt of the cationic complex [Pd{CH2SiPh2(CH2NC 6H10)-κ2C,N}(4-MePy)2] (11) is obtained by treating the starting dimer 3 with TlBF4 and 4-MePy. The addition of Ph2PCH2CH2PPh2 (dppe) to the starting dimer 3 leads to [{Pd2[CH2SiPh 2(CH2NC5H10)-κ2C,N] 2Cl2}-(u-dppe)] (13) or to [Pd{CH2SiPh 2(CH2NC5H10)-κ2C,N} (dppe)]Cl (11), depending on the stoichiometry. NMR data reveal that the Pd-N bond in 11 is transiently opened in solution. [Pd{CH2SiPh 2(CH2NC5H10)-κ2C,N} (dppe)]BF4 (14) is obtained from the latter compound upon treatment with TlBF4. The chelate complexes [Pd{CH2SiPh 2(CH2NC5H10)-κ2C,N} (acac)] (16) (acac = acetylacetonate) and [Pd{CH2SiPh 2(CH2NC5H10)-κ2C,N} (S2CNEt2)] (15) are obtained by reaction of the starting chloro-bridged dimer 3 with Tl(acac) and NaS2CNEt2, respectively. The solid state structures of palladacycles 3, 4, 8, 9, 10, and 15 were determined by X-ray diffraction methods.
