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Abstract The silylium‐like surface species [iPr3Si][(RFO)3Al−OSi≡)] activates (N^N)Pd(CH3)Cl (N^N=Ar−N=CMeMeC=N−Ar, Ar=2,6‐bis(diphenylmethyl)‐4‐methylbenzene) by chloride ion abstraction to form [(N^N)Pd−CH3][(RFO)3Al−OSi≡)] (1). A combination of FTIR, solid‐state NMR spectroscopy, and reactions with CO or vinyl chloride establish that1shows similar reactivity patterns as (N^N)Pd(CH3)Cl activated with Na[B(ArF)4]. Multinuclear13C{27Al} RESPDOR and1H{19F} S‐REDOR experiments are consistent with a weakly coordinated ion‐pair between (N^N)Pd−CH3+and [(RFO)3Al−OSi≡)].1catalyzes the polymerization of ethylene with similar activities as [(N^N)Pd−CH3]+in solution and incorporates up to 0.4 % methyl acrylate in copolymerization reactions.1produces polymers with significantly higher molecular weight than the solution catalyst, and generates the highest molecular weight polymers currently reported in copolymerization reactions of ethylene and methylacrylate.
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Activation of C−F Bonds by Electrophilic Organosilicon Sites Supported on Sulfated Zirconia
Abstract The reaction of allyltriisopropylsilane with partially dehydroxylated sulfated zirconium oxide (SZO) forms surface organosilicon species. Solid‐state NMR studies of the organosilicon functionalizedSZOshows that electrophilic [TIPS][SZO] sites are present on the surface, in addition to less reactive TIPS‐Oxand SiOxspecies. The electrophilic [TIPS][SZO] sites are strong Lewis acids from solid‐state31P NMR analysis of triethylphosphine oxide (O=PEt3) contacted materials. [TIPS][SZO] is active in hydrodefluorination reactions in the presence of Et3SiH.
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- Award ID(s):
- 1800561
- PAR ID:
- 10077228
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 130
- Issue:
- 45
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 15118-15121
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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