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Inverse electron demand Diels-Alder reactions performed on the double bonds in open cellular macroporous poly(dicyclopentadiene) monoliths yield a high degree of functionalisation (up to 2 mmol pyridazines per g or 8 mmol N per g) with grafted di(pyridyl)pyridazines in a single step.

The amination of racemic a-chiral aldehydes, 2-phenylpropanal derivatives, was investigated employing w-transaminases. By medium and substrate engineering the optical purity of the resulting b-chiral chiral amine could be enhanced to reach optical purities up to 99% ee. Using enantiocomplementary w-transaminases allowed us to access the (R)-as well as the (S)-enantiomer in most cases. It is important to note that the stereopreference of the w-transaminases found for a-chiral aldehydes did not correlate with the stereopreference previously observed for the amination of methyl ketones. In one case the stereopreference switched even upon exchanging a methyl substituent to a methoxy group.

Herein, highlights from the recent literature regarding functional dye-polymer conjugates obtained by ring opening metathesis polymerization (ROMP) are presented and the different approaches to incorporate dyes during the initiation, propagation, and termination step in ROMP are discussed. Applications in the field of chemical sensors, bioimaging, electroactive materials, self-assembly, photochromic and photoreactive materials are used to illustrate the versatility of ROMP as a technique to prepare complex functional materials. Graphical abstract

Herein, we report the synthesis of a novel, tetrazine-based conjugated polymer. Tetrazines have the benefit of being strong electron acceptors, while little steric hindrance is imposed on the flanking thiophene rings. Conversion of a suitably substituted nitrile precursor led to 3,6-bis(5-bromo-4-(2-octyldodecyl)thiophen-2-yl)-1,2,4,5-tetrazine (2OD-TTz). Palladium-catalyzed copolymerization of 2OD-TTz with a bithiophene monomer yielded an alternating tetrazine–quaterthiophene copolymer (PTz4T-2OD). The polymer PTz4T-2OD showed an optical band gap of 1.8 eV, a deep HOMO energy level of − 5.58 eV and good solubility. In combination with the non-fullerene acceptor ITIC-F, solar cells with power conversion efficiencies of up to 2.6% were obtained. Electronic supplementary material The online version of this article (10.1007/s10853-019-03551-3) contains supplementary material, which is available to authorized users.