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Herein, a highly efficient five‐step reaction sequence to BODIPYs is presented. The key step is the combination of transition metal‐catalyzed in‐situ generation of aldehydes and their subsequent organocatalytic activation to yield dipyrromethanes, which are further converted to the corresponding BODIPY. Classic syntheses towards BODIPYs have relied on aldehydes or acid chlorides, which are often not commercially available and rather sensitive to handle. The presented approach starts from readily available and stable alkenes or aryl‐bromides, which allows to extend the range of readily available BODIPYs that can be tailored for their specific use. The synthesis of 55 derivatives with overall yields of up to 78 % demonstrates the wide applicability and advantages of the presented method. [ABSTRACT FROM AUTHOR]

Herein we report an improved self‐assembling phosphorus ligand based on hydrogen bonding between pyridone/hydroxypyridine in the ligand backbone. The N‐pyrrolyl substituents significantly improve the π‐backbonding properties of the ligand. Rhodium, iridium and platinum complexes of the ligand were prepared and analyzed by NMR spectroscopy and x‐ray crystal structure analysis. A catalyst based on this ligand showed very high catalytic activity and linear regioselectivity in rhodium‐catalyzed hydroformylation of 1‐octene. The same ligand was applied in linear regioselective iridium‐catalyzed hydroformylation of 1‐octene. [ABSTRACT FROM AUTHOR]

Detailed mechanistic investigations on our previously reported synthesis of branched allylic esters by the rhodium complex‐catalyzed propargylic C−H activation have been carried out. Based on initial mechanistic studies, we present herein more detailed investigations of the reaction mechanism. For this, various analytical (NMR, X‐ray crystal structure analysis, Raman) and kinetic methods were used to characterize the formation of intermediates under the reaction conditions. The knowledge obtained by this was used to further optimize the previous conditions and generate a more active catalytic system. [ABSTRACT FROM AUTHOR]