Reactivity studies of carbon, phosphorus and sulfur-based acyl sites with tertiary oximes in gemini surfactants

Waste-derived biocatalysts for pesticide degradation

A green approach to produce a cellulose-derived biocatalyst containing hydroxamic acids targeted for the neutralization of toxic organophosphates is shown. The cellulose source, rice husk, is among the largest agricultural waste worldwide and can be strategically functionalized, broadening its sustainable application. Herein, rice husk was oxidized in different degrees, leading to carboxylic acid-based colloidal and solid samples. These were functionalized with hydroxamic acids via amide bonds and fully characterized. The hydroxamic acid derived biocatalysts were evaluated in the cleavage of toxic organophosphates, including the pesticide Paraoxon. Catalytic increments reached up to 10⁷-fold compared to non-catalyzed reactions. Most impressively, the materials showed P atom-selectivity and recyclability features. This guarantees only one reaction pathway that leads to less toxic products, hereby, detoxifies. Overall, highly sustainable catalysts are presented, that benefits from waste source, its green functionalization and is successfully employed for the promotion of chemical security of threatening organophosphates. To the best of our knowledge, this is the first report of a hydroxamate-derived rice husk (selectively modified at the C6 of cellulose) and its application in organophosphates reaction.

I2-Catalyzed Oxidative Coupling of Ketone Oximes and Dialkyl/Diarylphosphine Oxides

A new protocol for the oxidative coupling of ketone oximes with dialkyl/diarylphosphine oxides to synthesize O-(dialkylphosphinyl)ketone oximes has been developed. Hydrogen peroxide is used as a green oxidizing agent, and molecular iodine is used as a nonmetal catalyst. The reaction has a high atom economy, with water as the only byproduct. O-(Dialkylphosphinyl)ketone oximes with 26 examples have been obtained with high yields. Furthermore, the product may be transformed into other molecules, i.e., by reduction.

Modernization of surfactant chemistry in the age of gemini and bio-surfactants: a review

This review contains elaborate discussions on the efficiencies of gemini and bio-surfactants as modern generation green chemicals in various fields.