o-Diarylphosphinoferrocene Sulfonate Palladium Systems for Nonalternating Ethene–Carbon Monoxide Copolymerization
摘要:
A series of ferrocene-derived o-diarylphosphino/sulfonate ligands were prepared. Treatment of the o-diphenylphosphinoferrocene sulfonic acid (2a) with (allyl)PdCl dimer and sodium carbonate as the base gave the corresponding chelate (Fc-O,P)Pd(pi-allyl) complex 7a (as a mixture of two isomers). In the presence of pyridine instead of Na2CO3 the analogous reaction yielded the square-planar (Fc-O,P)Pd(Cl)pyridine complex 8a. Both systems were characterized by X-ray diffraction. Reaction of the series of three differently -P(aryl)(2)-substituted (Fc-O,P)H ligands with PdMe2(tmeda) gave the respective (Fc-O,P)PdMe(pyridine) derivatives (11). All three examples 11a,b,c and one precursor complex, [(Fc-O,P)PdMe](2)(tmeda) (10a), were characterized by X-ray diffraction. The ligand system o-bis-(o-anisyl)phosphinoferrocene sulfonic acid (2b) formed an active catalyst for ethene/CO nonalternating copolymerization upon treatment with Pd(OAc)(2) in methanol. Up to ca. 25% extra ethene incorporation was obtained at an ethene/CO partial pressure ratio of ca. 10:1. This catalyst system and its equivalent derived from the preformed (Fc-O,P)PdMe(pyridine) precursor complex (11b) showed reasonable catalyst activities under these conditions.
o-Diarylphosphinoferrocene Sulfonate Palladium Systems for Nonalternating Ethene–Carbon Monoxide Copolymerization
摘要:
A series of ferrocene-derived o-diarylphosphino/sulfonate ligands were prepared. Treatment of the o-diphenylphosphinoferrocene sulfonic acid (2a) with (allyl)PdCl dimer and sodium carbonate as the base gave the corresponding chelate (Fc-O,P)Pd(pi-allyl) complex 7a (as a mixture of two isomers). In the presence of pyridine instead of Na2CO3 the analogous reaction yielded the square-planar (Fc-O,P)Pd(Cl)pyridine complex 8a. Both systems were characterized by X-ray diffraction. Reaction of the series of three differently -P(aryl)(2)-substituted (Fc-O,P)H ligands with PdMe2(tmeda) gave the respective (Fc-O,P)PdMe(pyridine) derivatives (11). All three examples 11a,b,c and one precursor complex, [(Fc-O,P)PdMe](2)(tmeda) (10a), were characterized by X-ray diffraction. The ligand system o-bis-(o-anisyl)phosphinoferrocene sulfonic acid (2b) formed an active catalyst for ethene/CO nonalternating copolymerization upon treatment with Pd(OAc)(2) in methanol. Up to ca. 25% extra ethene incorporation was obtained at an ethene/CO partial pressure ratio of ca. 10:1. This catalyst system and its equivalent derived from the preformed (Fc-O,P)PdMe(pyridine) precursor complex (11b) showed reasonable catalyst activities under these conditions.
Redox‐Controlled Olefin (Co)Polymerization Catalyzed by Ferrocene‐Bridged Phosphine‐Sulfonate Palladium Complexes
作者:Min Chen、Bangpei Yang、Changle Chen
DOI:10.1002/anie.201507274
日期:2015.12.14
interconversion between neutral and oxidized forms of palladium complexes containing ferrocene‐bridged phosphine sulfonate ligands was demonstrated. The activity of these palladium complexes could be controlled using redox reagents during ethylene homopolymerization, ethylene/methyl acrylate copolymerization, and norbornene oligomerization. Specifically in norbornene oligomerization, the neutral complexes