Carbotrifluoromethylations of C-C Multiple Bonds (Excluding Aryl- and Alkynyltrifluoromethylations).

Organofluorine chemistry has become an expanding area of research in organic chemistry and drug design. The synthesis of fluorine-containing molecules has received high significance in synthetic chemistry. Trifluoromethylative difunctionalizations of carbon-carbon multiple bonds with the simultaneous introduction of a CF3 group and another function have considerable relevance. Because of the high importance of carbon-carbon bond-forming reactions in organic synthesis, carbotrifluoromethylations are considered to be a field of synthetic chemistry of increasing importance. Our current goal in this review is to summarize recent developments of various trifluoromethylation reactions (excluding aryl- and alkynyl-trifluoromethylations) taking into consideration several main approaches, such as alkenyltrifluoromethylation, alkyltrifluoromethylation, carbonyltrifluoromethylation, and cyanotrifluoromethylation reactions.

Aminoglycoside Conjugation for RNA Targeting: Antimicrobials and Beyond.

Natural aminoglycosides are therapeutically useful antibiotics and very efficient RNA ligands. They are oligosaccharides that contain several ammonium groups able to interfere with the translation process in prokaryotes upon binding to bacterial ribosomal RNA (rRNA), and thus, impairing protein synthesis. Even if aminoglycosides are commonly used in therapy, these RNA binders lack selectivity and are able to bind to a wide number of RNA sequences/structures. This is one of the reasons for their toxicity and limited applications in therapy. At the same time, the ability of aminoglycosides to bind to various RNAs renders them a great source of inspiration for the synthesis of new binders with improved affinity and specificity toward several therapeutically relevant RNA targets. Thus, a number of studies have been performed on these complex and highly functionalized compounds, leading to the development of various synthetic methodologies toward the synthesis of conjugated aminoglycosides. The aim of this review is to highlight recent progress in the field of aminoglycoside conjugation, paying particular attention to modifications performed toward the improvement of affinity and especially to the selectivity of the resulting compounds. This will help readers to understand how to introduce a desired chemical modification for future developments of RNA ligands as antibiotics, antiviral, and anticancer compounds.

Copper-Catalyzed N-Arylation of Nitroenamines with Diaryliodonium Salts.

A novel synthetic methodology was developed for the N-arylation of nitroenamine derivatives utilizing diaryliodonium triflates and copper(I) chloride as a catalyst. The procedure enables the easy aryl transfer from the hypervalent species under mild catalytic conditions with unusual heteroatom preference and high efficiency.

Modular Copper-Catalyzed Synthesis of Chromeno[4,3-b]quinolines with the Utilization of Diaryliodonium Salts.

A novel, highly modular synthetic method with high functional group tolerance was developed for the construction of chromenoquinoline derivatives from arylpropynyloxy-benzonitriles and diaryliodonium triflates via an oxidative arylation-cyclization path. The copper(I) chloride catalyzed reaction is presumed to involve the formation of highly active arylcopper(III) species.

Gold-Catalyzed Direct Alkynylation of Azulenes.

A novel catalytic method for the direct C-H alkynylation of azulenes is developed. The gold catalyzed functionalization of this special carbacycle is achieved with hypervalent iodonium reagent TIPS-EBX under mild reaction conditions. With the aid of the developed procedure, several TIPS alkynylated azulene derivatives were synthesized bearing important functional groups for further functionalization.