Development of a Scalable Process for the Insecticidal Candidate Tyclopyrazoflor. Part 3. A Scalable Synthesis of Methyl 3-((3,3,3-Trifluoropropyl)thio)propanoate via Thiol–Ene Chemistry

Long-Chain Molecules with Agro-Bioactivities and Their Applications

Long-chain molecules play a vital role in agricultural production and find extensive use as fungicides, insecticides, acaricides, herbicides, and plant growth regulators. This review article specifically addresses the agricultural biological activities and applications of long-chain molecules. The utilization of long-chain molecules in the development of pesticides is an appealing avenue for designing novel pesticide compounds. By offering valuable insights, this article serves as a useful reference for the design of new long-chain molecules for pesticide applications.

Bioisosteric-Replacement-Driven Lead Optimization of Tyclopyrazoflor

A heterocyclic replacement strategy has been applied attempting to further optimize the biological properties of the new insecticide tyclopyrazoflor, a pyridinyl-pyrazole compound with excellent activity against sap-feeding insects recently discovered by Corteva. Our research program on this novel chemical class of insecticide was targeted to evaluate the importance of both the pyridyl and pyrazole moieties on the biological activity, properties, and structure-activity. Synthetic methodologies have been developed delivering our designed target compounds in moderate to good yields. In our attempt to rationalize the biological activity differences of tyclopyrazoflor analogues, a potential surface analysis based on a density functional theory (DFT) calculation and DFT-derived Multiwfn and VMD program model was performed. Furthermore, the SwissBioisostere online database was applied as a great source for inspiration for bioisosteric replacements.

Bifunctional Iminophosphorane-Catalyzed Enantioselective Sulfa-Michael Addition to Unactivated α,β-Unsaturated Amides

The first metal-free catalytic intermolecular enantioselective Michael addition to unactivated α,β-unsaturated amides is described. Consistently high enantiomeric excesses and yields were obtained over a wide range of alkyl thiol pronucleophiles and electrophiles under mild reaction conditions, enabled by a novel squaramide-based bifunctional iminophosphorane catalyst. Low catalyst loadings (2.0 mol %) were achieved on a decagram scale, demonstrating the scalability of the reaction. Computational analysis revealed the origin of the high enantiofacial selectivity via analysis of relevant transition structures and provided substantial support for specific noncovalent activation of the carbonyl group of the α,β-unsaturated amide by the catalyst.

Synthetic approaches to the 2015-2018 new agrochemicals

In this review, the synthesis of 33 agrochemicals that received an international standardization organization (ISO) name between January 2015 and December 2018 is described. The aim is to showcase the broad range and scope of reactions, reagents and intermediates used to discover and produce the latest active ingredients addressing the crop protection industry's needs.