Decarbethoxylative Arylation Employing Arynes: A Metal-Free Pathway to Arylfluoroamides

Ligand-Induced Regioselectivity in Metal-Catalyzed Aryne Reactions Using Borylaryl Triflates as Aryne Precursors

The utility of reactions using unsymmetrically substituted aryne intermediates can be negatively impacted by issues with regioselectivity as these reactions are substrate controlled. This leaves no avenues for improving regioselectivity without altering the substrate which has led to numerous reports about how to enhance or reverse this regioselectivity in metal-free aryne reactions by changing the electronics. To the best of our knowledge, no such studies exist for systems with metal-bound aryne intermediates, which often suffer from worse regioselectivities. Herein we report a means of achieving regioselectivity in a metal-catalyzed aryne difunctionalization via catalyst control. Through the use of an unsymmetrical ligand environment, selectivity can be induced (up to 9:91 r.r.). These investigations demonstrate that catalyst design can influence selectivity in metal-catalyzed aryne reactions.

H-F bond insertions into α-diazo carbonyl compounds

A reaction for H-F bond insertion into α-diazo carbonyl compounds is reported. The protocol describes a simple reaction setup employing commercially available HF·pyr (Olah reagent) as the fluorine source. The method is rapid and practical, and allows access to a broad range of α-fluorinated carbonyl compounds in generally good yields.

TMSCF2 Br-Enabled Fluorination-Aminocarbonylation of Aldehydes: Modular Access to α-Fluoroamides

A protocol for the modular assembly of the α-fluoroamide motif has been developed, which provides a practical method for the efficient synthesis of structurally diverse α-fluoroamides from easily available aldehydes and tertiary amines through a three-component fluorination-aminocarbonylation process. The key to the success of this process is taking advantage of the multiple roles of the unique difluorocarbene reagent TMSCF₂ Br (TMS=trimethylsilyl). The mechanism of the process involves the 1,2-fluorine and oxygen migrations of the in situ formed TMS-protected α-aminodifluoromethyl carbinol intermediates, which represents a new type of deoxyfluorination reaction.

Wonderful fusion of organofluorine chemistry and decarboxylation strategy

Decarboxylation strategy has been emerging as a powerful tool for the synthesis of fluorine-containing organic compounds that play important roles in various fields such as pharmaceuticals, agrochemicals, and materials science. Considerable progress in decarboxylation has been made over the past decade towards the construction of diverse valuable fluorinated fine chemicals for which the fluorinated part can be brought in two ways. The first way is described as the reaction of non-fluorinated carboxylic acids (and their derivatives) with fluorinating reagents, as well as fluorine-containing building blocks. The second way is dedicated to the exploration and the use of fluorine-containing carboxylic acids (and their derivatives) in decarboxylative transformations. This review aims to provide a comprehensive summary of the development and applications of decarboxylative radical, nucleophilic and cross-coupling strategies in organofluorine chemistry.

Utilization of Unsymmetric Diaryliodonium Salts in α-Arylation of α-Fluoroacetoacetamides

The use of unsymmetric diaryliodonium salts as a versatile class of arylating agents has been demonstrated by developing a novel strategy to quickly access α-arylated α-fluoroacetoacetamides. The protocol provides a convenient metal-free method for the α-arylation of a diverse class of fluorinated acetoacetamides, and the products are obtained in good yields. The strategy, upon use of electron-deficient diaryliodonium salts as an arylating agent, provides α-fluoroacetamides through a spontaneous arylation/deacylation cascade.

Recent advances in the synthesis of fluorinated compounds via an aryne intermediate

In this review, the usefulness of aryne intermediates for the synthesis of various fluorinated organic compounds during the last decade has been demonstrated.

Structure of 2-chloro-N-(p-tol-yl)propanamide

Two independent samples of the title compound, alternatively 2-chloro-N-(4-methylphenyl)prop-an-amide, C10H12ClNO, 1, were studied using Cu Kα, 1a, and Mo Kα, 1b, radiation as part of a continuous crystallization study. The mol-ecule crystallizes with disorder in the Cl/terminal methyl positions [occupancies for the major disorder component of 0.783 (2) in 1a and and 0.768 (2) in 1b] and exhibits N-C bond lengths of 1.3448 (19), 1.344 (2) Å, C=O bond lengths of 1.2233 (18) and 1.2245 (19) Å and an acetamide moiety C-N-C-C torsion angle of 179.00 (13), 178.97 (14) ° for 1a and 1b, respectively. In the crystal, chains along the a axis are formed via N-H⋯O hydrogen bonds between acetamide groups, as well as C-H⋯O inter-actions. These chains arrange themselves into parallel running stacks which display weak C-Cl⋯O=C halogen bonding as well as weak C-H⋯π inter-actions.