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We report herein an unprecedented synthesis of difluoromethoxylated nitrogen‐containing heterocycles from the corresponding α‐(difluoromethoxy)ketones as versatile building blocks. Pyrazoles, isoxazoles and pyrimidines could be obtained via an enaminone intermediate, whereas in the direct reaction of α‐(difluoromethoxy)ketones with arylhydrazines, a Fischer indole synthesis was achieved. All these scaffolds, which are uncommon, or even sometimes novel, due to the directly attached emerging fluorinated group (EFG) −OCF2H, might be of high potential in life sciences and appear as an interesting alternative to more and more controversial classical fluorinated groups, such as the ubiquitous trifluoromethyl group. [ABSTRACT FROM AUTHOR]

Based on an easy and scalable method for the synthesis of quinoline derivatives substituted by fluorinated groups at both the C‐2 and C‐4 positions developed in our laboratory, we have devised an approach to the synthesis of a new series of unprecedented 2,4‐bis(fluoroalkyl)quinoline‐3‐carboxylates in just two steps. After standard saponification, the latter gave the corresponding 2,4‐bis(fluoroalkyl)quinoline‐3‐carboxylic acids, which served as pivotal intermediates for post‐functionalization reactions. Indeed, the carboxylic group could then be derivatized according to known procedures to introduce chemical diversity at the C‐3 position of these unprecedented structures. The resulting highly functionalized quinolines can serve as a platform for the development of biologically active molecules with strong potential for agrochemical research. [ABSTRACT FROM AUTHOR]

Abstract: A new strategy was developed using fluorinated acetoacetates, malononitrile, and fluoroalkyl amino reagents (FARs) to access unprecedented 4,6‐bis(fluoroalkyl)pyrimidine‐5‐carboxylates, their carboxylic acid analogues, and 4‐amino‐6‐(fluoroalkyl)pyrimidine‐5‐carbonitriles. An efficient cyclization step using suitable amidines was developed under microwave irradiation, providing the desired pyrimidines rapidly and efficiently. Standard saponification conditions were applied from carboxylate derivatives to access to the corresponding carboxylic acids. These new valuable building blocks, bearing either a single or two emergent fluorinated substituents, hold strong potential for medicinal and agrochemical research. [ABSTRACT FROM AUTHOR]

A novel approach towards highly functionalized fluoroalkyl pyrazoles was developed by using fluoroalkyl amino reagents in combination with a variety of fluorinated ketimines. Tuneable introduction of fluoroalkyl groups in the 3- and 5-positions was possible by using vinamidinium intermediates or the corresponding enamino ketones after hydrolysis. These high-value building blocks can give rise to a large number of analogues for bioactivity screening and discovering new heterocyclic bioactive ingredients in various life science fields. [ABSTRACT FROM AUTHOR]

Biaryl-substituted monophosphine-based ligands have been synthesized by transition-metal-free 'ARYNE' cross-coupling reaction of aryllithiums with 1,2-dibromobenzene and subsequent regioselective functionalization through bromine-lithium interconversion. These ligands were employed in palladium-catalyzed C-N bond-forming reactions. The reaction was found to be general with wide substrate applicability. A wide variety of both primary and secondary amines were successfully coupled with an array of differently substituted halobenzenes under microwave irradiation to give the expected products in good to excellent yields. A number of biaryl-substituted phosphine ligands screened for the coupling reaction showed that steric bulk and the electronic properties of substituents on phosphorus play a crucial role in governing the catalytic activity of C-N cross-coupling reactions. [ABSTRACT FROM AUTHOR]

Fluoroalkyl pyrazoles, which are key building blocks in agrochemistry and promising candidates in life ‐ sciENce ‐ oriENted research, have shown much potENtial in accessing a variety of bis(fluoroalkyl)pyrazoles with tunable regioselectivity of the hydrazine addition, via two intermediates of opposed reactivity. The two strategies are represENted by one slingshot aiming at two differENt targets, with a background of crops, forests, and laboratory activities. More information can be found in the Full Paper by S. PazENok, F. R. Leroux et al. on page 11239. [ABSTRACT FROM AUTHOR]