147300-25-2Relevant articles and documents
Synthesis of Polysiloxane-Bound (Ether-phosphine)palladium Complexes. Stoichiometric and Catalytic Reactions in Interphases 1
Lindner, Ekkehard,Schreiber, Rudolf,Schneller, Theodor,Wegner, Peter,Mayer, Hermann A.,Gpel, Wolfgang,Ziegler, Christiane
, p. 514 - 525 (2008/10/09)
The reaction of two equiv of the monomeric ether-phosphine O,P ligand (MeO)3Si(CH2)3(Ph)PCH2-Do [1a(T0), 1b(T0)] {Do = CH2OCH3 [1a(T0)], CHCH2CH2CH2O [1b(T0)]} with PdCl2(COD) yields the monomeric palladium(II) complexes Cl2Pd(P～O)2 [2a(T0)2, 2b(T0)2]. The compounds 2a(T0)2 and 2b(T0)2 are sol-gel processed with variable amounts (y) of Si(OEt)4 (Q0) to give the polysiloxane-bound complexes 2a(Tn)2(Qk)y, 2b(Tk)2(Qk)y (Table 1) {P～O = η1-P-coordinated ether-phosphine ligand; for Tn and Qk, y = number of condensed T type (three oxygen neighbors), Q type (four oxygen neighbors) silicon atoms; n and k = number of Si-O-Si bonds; n = 0-3; k = 0-4; 2a(Tn)2(Qk)y = {[M]-SiOn/2(OX)3-n}2[SiOk/2 (OX)4-k]y, [M] = (Cl2Pd)1/2-(Ph)P(CH2Do)(CH2) 3-, X = H, Me, Et}. The complexes 2b(Tn)2(Qk)y (y = 4, 12, 36) show high activity and selectivity in the hydrogenation of 1-hexyne and tolan. The dicationic complexes [Pd(PO)2][SbF6]2 [3a(T0)2, 3b(T0)2] are formed by reacting Cl2Pd(P～O)2 with 2 equiv of a silver salt {PO = η2-OP-coordinated ether-phosphine ligand; 3a(T0)2, 3b(T0)2 = [M]-SiOMe3; [M] = {[Pd2+]1/2P(Ph)(CH2CH2OCH 3)(CH2)3-}{SbF6} (a), {[Pd2+]1/2P(Ph)(CH2CHCH2CH 2CH2O)(CH2)3-} {SbF6} (b)}. Their polysiloxane-bound congeners 3a(Tn)2, 3b-(Tn)2 {[M]-SiOn/2(OX)3-n} are obtained if a volatile, reversible bound ligand like acetonitrile is employed during the sol-gel process. The bis(chelate)palladium(II) complexes 3a(Tn)2,3b(Tn)2 are catalytic active in the solventfree CO-ethene copolymerization, producing polyketones with chain lengths comparable to those obtained with chelating diphosphine ligands. The polysiloxane-bound palladium (O) complexes 5a(Tn)2(Qk)2, 5b(Tn)2(Qk)4 {-[M]-SiOn/2(OX)3-n}2[SiO k-2(OX)4-k]4, [M] = [(dba)Pd]1/2P(Ph)(CH2Do)(CH2)3-} undergo an oxidative addition reaction with iodobenzene in an interphase with formation of the complexes PhPd (I)(P～O)2·4SiO2 [6a(Tn)2- (Qk)4, 6b(Tn)2(Qk)4] {[M]-SiO1/2(OX)3-n]2[SiOk/2(OX) 4-k]4, [M] = [PhPd (I)]]1/2P(Ph)(CH2Do)(CH2)3-}, which insert carbon monoxide into the palladium-aryl bond even in the solid state.
