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High refractive index (HRI) materials play an important role in optic-electronic devices. In this study, two compounds with high content of naphthalene groups, 1,5-dithiolnaphthalene and 1,3,5-tris(naphthalyl-ethylnyl) benzene, are selected as 'A2' and 'B3' monomers, respectively to prepare hyperbranched HRI polymers. Metal-free radical-initiated 'A2 + B3' thiol-yne polyaddition is conducted successfully at different monomer molar ratios even for those sterically demanding molecules being able to adjust the molar mass as well as RI. Polymers with refractive index up to 1.79 at 589.7 nm are obtained, which are among the highest RI values so far reported for pure polymer-based materials. The high RI, based on the high molar refraction of naphthalene group, metal-free and easy one-pot synthesis, high transparency in the visible area, good thermal stability, good solubility, and easy processability into thin films, make these polymers excellent candidates for optic-electronic applications. [ABSTRACT FROM AUTHOR]

Chain-growth catalyst-transfer polycondensations of AB-type monomers is a new and rapidly developing tool for the preparation of well-defined π-conjugated (semiconducting) polymers for various optoelectronic applications. Herein, we report the Pd/P tBu3-catalyzed Negishi chain-growth polycondensation of AB-type monomers, which proceeds with unprecedented TONs of above 100 000 and TOFs of up to 280 s−1. In contrast, related AA/BB-type step-growth polycondensation proceeds with two orders of magnitude lower TONs and TOFs. A similar trend was observed in Suzuki-type polycondensation. The key impact of the intramolecular (vs. intermolecular) catalyst-transfer process on both polymerization kinetics and catalyst lifetime has been revealed. [ABSTRACT FROM AUTHOR]

Ni-catalyzed polymerization of anion-radical complexesformed upon mixing of 2,6-bis(2-bromothien-5-yl)naphthalene-1,4,5,8-tetracarboxylic-N,N′-bis(2-octyldodecyl) diimide and activated Znpowder was investigated. We provide experimental evidence that thepolymerization involves the chain-growth mechanism and proceeds viaNi(0) complexes which were previously proposed to be key intermediatesin other chain-growth catalyst-transfer polycondensations (CTPs),such as Kumada CTP of thiophenic monomers. DFT calculations predicta remarkable stability of the naphthalene diimide-based Ni(0) complexes.A plausible polymerization mechanism is proposed. [ABSTRACT FROM AUTHOR]

Strongly electron-deficient (n-type) main-chain π-conjugated polymers are commonly prepared via well-established step-growth polycondensation protocols which enable limited control over polymerization. Here we demonstrate that activated Zn and electron-deficient brominated thiophene-naphthalene diimide oligomers form anion-radical complexes instead of conventional Zn-organic derivatives. These highly unusual zinc complexes undergo Ni-catalyzed chain-growth polymerization leading to n-type conjugated polymers with controlled molecular weight, relatively narrow polydispersities, and specific end-functions. [ABSTRACT FROM AUTHOR]