64740-46-1Relevant articles and documents
(Phenylalkyl)palladium complexes containing β-hydrogen atoms: Synthesis and characterization of [PdR2(dppe)], [PdR(SPh)(dppe)] (R = CH2CH2Ph, CH2CH2CH2Ph, CH2CHMePh), and [Pd(CH2CH2CH2Ph)X(dppe)] (X = I, Br, Cl)
Spaniel, Thomas,Schmidt, Harry,Wagner, Christoph,Merzweiler, Kurt,Steinborn, Dirk
, p. 2868 - 2877 (2007/10/03)
Reactions of HgR2 (R = CH2CH2Ph, 1a; CH2CH2CH2Ph, 1b; CH2CHMePh, 1c) (prepared from HgCl2 and the requisite Grignard compounds) with lithium in toluene afforded (phenylalkyl)lithium compounds LiR (2a-c) in yields of between 64 and 81%. At -30 °C, they react with [PdCl2(dppe)] [dppe = 1,2-bis(diphenylphosphanyl)ethane] yielding bis(phenylalkyl)palladium(II) complexes [PdR2(dppe)] (3a-c) which were isolated (Tdec = 159 °C, 3a; 80 °C, 3b; 145 °C, 3c) and fully characterized by 1H, 13C, and 31P NMR spectroscopy. Single-crystal X-ray diffraction of [Pd(CH2CH2Ph)2(dppe)] (3a) showed that the palladium atom is square-planar coordinated by two 2-phenylethyl ligands and the dppe ligand. The two CH2CH2Ph ligands exhibite nearly a fully staggered conformation. Overall, a good approximation for the complex is that it has C2 symmetry with the C2 axis defined by the Pd atom and the midpoint of the central C-C bond of the dppe ligand. Bis(phenylalkyl)palladium complexes 3a and 3b reacted with PhSH in a 1:1 ratio yielding [PdR(SPh)(dppe)] (R = CH2CH2Ph, 5a; CH2CH2CH2Ph, 5b), whereas in the case of complex 3c, besides [Pd(CH2CHMePh)(SPh)(dppe)] (5c), a considerable amount of [Pd(SPh)2(dppe)] (6a) was formed. Reactions of 3b with the less acidic alkanethiols iPrSH and tBuSH resulted in the formation of [Pd(CH2CH2CH2Ph)(SR′)(dppe)] (R′ = iPr, 5d; tBu, 5e) along with smaller amounts of [Pd(SR′)2(dppe)] (6) and [Pd(dppe)2] (7). Furthermore, complex 3b was found to react in THF with disulfides R′SSR′ (R· = Ph, Bz, Me), yielding [Pd(CH2CH2CH2Ph)(SR′)(dppe)] (R′ = Ph, 5b; Bz, 5f, Me, 5g) with small amounts (3-13%) of [Pd(SR′)2(dppe)] (6) as side products. The corresponding reaction with MeSe-SeMe afforded [Pd(CH2CH2CH2Ph)(SeMe)(dppe)] (8a) and 3% of [Pd(SeMe)2(dppe)] (9a) and [Pd(dppe)2] (7). Reactions of complex 5b with MeI and H2C=CHCH2Br in tetrahydrofuran and with neat H2C=CHCH2Cl readily proceeded at -30 °C to give halo(3-phenylpropyl)palladium complexes [Pd(CH2CH2CH2Ph)X(dppe)] (X = I, 10a; Br, 10b; Cl, 10c). They were isolated as pale yellow powdery/microcrystalline substances and fully characterized by 13C and 31P NMR spectroscopy. Solutions of complexes 10 in THF decompose rapidly above -30 °C. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
ZUR BILDUNGSWEISE VON 1-PHENYLPROPYLLITHIUM AUS BENZYLLITHIUM UND ETHYLEN IN TETRAHYDROFURAN
Maercker, Adalbert,Stoetzel, Reinhard
, p. 1 - 12 (2007/10/02)
3-Phenylpropyllithium primarily formed by the addition of benzyllithium to ethylene in THF does not undergo an intramolecular 1,3-proton shift to 1-phenylpropyllithium.Fast protonation by the solvent takes place instead, yielding n-propylbenzene and new ethylene.An equilibrium is then established between n-propylbenzene and additional benzyllithium, with the formation of toluene and 1-phenylpropyllithium; the equilibrium, however, strongly favours the starting materials (K293=1.1*10-4).As, on the other hand, 1-phenylpropyllithium reacts with ethylene much more rapidly than does benzyllithium, it is removed from the equilibrium and mainly branched secondary products are still obtained.
