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To overcome aggregation of porphyrins and realize heterogeneous catalysis with high active site loadings, the twisted ZnTHP-Me2Si and layered ZnTHP-Ph2Si are synthesized through cross-linking zinc tetraphenylporphyrin (ZnTHP) respectively with dichlorodimethylsilane...

Reversible deactivation radical polymerization (RDRP) is a facile and highly efficient technique for the synthesis of well-defined polymer with precise structure. dl-Methionine (Met) as a RDRP control agent is described and assessed for RDRP of styrene (St) and methyl methacrylate (MMA) with AIBN as radical initiator at 75 °C, which enables excellent control of this polymerization. The addition of dl-Methionine significantly decreased the dispersity (Ð) of the polymers for both monomers and first-order linear kinetic plots of polymethyl methacrylate (PMMA) are observed in DMSO. Considering the heat resistance of dl-Methionine, kinetic studies indicate that polymerization develops at a faster rate at higher reaction temperature (100 °C) with the same dl-Methionine content. Well-defined polymethyl methacrylate-block-polystyrene (PMMA-block-PSt) is successfully achieved by the chain extension reaction that demonstrates the high end fidelities of this polymerization approach. The system allows the use of dl-Methionine, a rich source and easily synthesized agent, to mediate RDRP strategy.

Dihydroquinolin-2(1H)-ones (DHQOs) represent a class of valuable bioactive compounds with six-membered nitrogen-containing heterocyclic structures. The development of simple, mild, and efficient synthetic methods has been widely considered by synthetic chemists. In this review, we have summarized a series of different synthetic strategies for the synthesis of DHQOs via the catalytic annulation of α,β-unsaturated N-arylamides in the past decade, including covering electrophilic cyclization, radical initiated cyclization, and photochemical cyclization reactions. Additionally, the substrate scope and mechanistic details are also discussed. This paper provides a useful reference for the development of diverse synthesis methodologies of DHQO.

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