Nitrogen heterocycles have found a key role in biologically active natural products. Pyridones, specifically 2‐pyridone and 2,4‐dihydoxypyridine are an extensive class of compounds with reported occurrence in many natural products. Therefore, the methods for generation of functionalized pyridones are of great interest since their discovery. From traditional coupling to transition metal catalyzed C−H functionalization and transition metal free C−H functionalization, this field has witnessed enormous growth. In the present review, we aim to present a comprehensive overview of pyridone functionalization for young researchers and invite the scientific community to come up with more environment friendly, economic and transition metal free methodologies for corresponding functionalizations.

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Herbicides are applied for effective weed management in order to increase the crop yield. In recent decades, the overuse of these chemicals has posed adverse effects on different biotic components of the environment. Pretilachlor has been widely used during last few decades for weed management in paddy crop. Its excessive use may prove fatal for environment, various organisms, and nontarget plants. Thus, it is pertinent to know the extent to which herbicide residues remain in environment. The potential mobility and the release rate of herbicide in the soil are important factors governing ecotoxicological impact and degradation rate. Therefore, several techniques are being investigated for its effective removal from the contaminated sites. Furthermore, efforts have also been made to study the degradation of pretilachlor by various physicochemical processes, resulting into the formation of different types of metabolites. This review summarizes the available information on environmental fate, various degradation processes, microbial biotransformation, metabolites formed, ecotoxicological effects, techniques for detection in environmental samples, effect of safener, and various control release formulations for sustained release of pretilachlor in applied fields. The information so obtained will be very advantageous in deciding the future policies for safe and judicious use of the herbicide by maintaining health and environmental sustainability.