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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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A New Platform of B/N‐Doped Cyclophanes: Access to a π‐Conjugated Block‐Type B 3 N 3 Macrocycle with Strong Dipole Moment and Unique Optoelectronic Properties
Abstract We herein describe a new design principle to achieve B/N‐doped cyclophane where an electron‐donor block of three triarylamines (Ar3N) and an acceptor block of three triarylboranes (Ar3B) are spatially separated on opposite sides of the π‐extended ring system. DFT computations revealed the distinct electronic structure of theblock‐type macrocycleMC‐b‐B3N3with a greatly enhanced dipole moment and reduced HOMO–LUMO energy gap in comparison to its analogue with alternating B and N sites,MC‐alt‐B3N3. The unique arrangement of borane acceptor Ar3B and amine donor Ar3N components inMC‐b‐B3N3induces exceptionally strong intramolecular charge transfer in the excited state, which is reflected in a largely red‐shifted luminescence at 612 nm in solution. The respective linear open‐chain oligomerL‐b‐B3N3was also synthesized for comparison. Our new approach to donor–acceptor macrocycles offers important fundamental insights and opens up a new avenue to unique optoelectronic materials.
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- Award ID(s):
- 1954122
- PAR ID:
- 10370313
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 20
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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