Radical Fluoroalkylation Reactions

Recent protocols and reactions for catalytic radical perfluoroalkylations will be described. The production of perfluoroalkyl radicals (RF = CnF2n+1, n ≥ 2), which effect both addition and substitution reactions on organic substrates, can be realized through a range of diverse methods such as the well-established visible-light transition-metal-mediated photocatalysis, organic-dye-photocatalyzed reactions, electron donor-acceptor complexes, and more recently frustrated Lewis pairs. Thus, perfluoroalkylation reactions of carbon-carbon multiple bonds, isocyanides, nitrones, hydrazones, β-keto esters, α-cyano arylacetates, sulfides, and (hetero)arenes will be described. Special emphasis will be placed on examples published after 2015, where higher fluorinated series of fluoroalkylating reagents are studied.Fil: Barata Vallejo, Sebastian. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cooke, María Victoria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Postigo, A.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Orgánica; Argentin

S_NAr Isocyanide Diversification

Isocyanides are important building blocks in organic synthesis; however, their synthesis is time and resource consuming and often unpleasant due to their smelly nature. Diversification of isocyanides can be accomplished by de novo synthesis or from already existing isocyanides. In this work, we report for the first-time isocyanide diversification based on nucleophilic aromatic substitution of suitable precursor isocyanides. The mild conditions allow for easy access to multiple novel isocyanides useful in organic synthesis. The resulting isocyanides are solid and non-noxious, yet react nicely in multicomponent reactions

Multicomponent Reactions and Their Libraries - a New Approach to Preparative Organic Chemistry

Classical chemical syntheses from n starting materials usually require sequences of at least n-I preparation steps, including separation and purification of the intermediates. A perfect alternative for the rapid syntheses of a large variety of agrichemically and pharmaceutically relevant products are one-pot syntheses by multicomponent reactions (MCR)on the basis of isocyanides. Four to seven different types of components mixed in a reaction vessel undergo the transformation to one molecule. Due to the last irreversible step that involves the isocyanides, a stable product results in quantitative yields. Using more than one representative of each type of starting materials (i.e. different isocyanides, amines, etc.) in the same vessel, all possible combinations will lead to a molecular library with hundreds and thousands of products formed according to a given reaction scheme. The design of such syntheses and the handling of the results require adequate mathematics and computer tools

The Chemistry of Phenylimidotechnetium(V) Complexes with Isocyanides: Steric and Electronic Factors

Organometallic approaches are of ongoing interest for the development of novel functional 99mTc radiopharmaceuticals, while the basic organotechnetium chemistry seems frequently to be little explored. Thus, structural and reactivity studies with the long-lived isotope 99Tc are of permanent interest as the foundation for further progress in the related radiopharmaceutical research with this artificial element. Particularly the knowledge about the organometallic chemistry of high-valent technetium compounds is scarcely developed. Here, phenylimido complexes of technetium(V) with different isocyanides are introduced. They have been synthesized by ligand-exchange procedures starting from [Tc(NPh)Cl3(PPh3)2]. Different reactivity patterns and products have been obtained depending on the steric and electronic properties of the individual ligands. This involves the formation of 1:1 and 1:2 exchange products of Tc(V) with the general formulae [Tc(NPh)Cl3(PPh3)(isocyanide)], cis- or trans-[Tc(NPh)Cl3(isocyanide)2], but also the reduction in the metal and the formation of cationic technetium(I) complex of the formula [Tc(isocyanide)6]+ when p-fluorophenyl isocyanide is used. The products have been studied by single-crystal X-ray diffraction and spectroscopic methods, including IR and multinuclear NMR spectroscopy. DFT calculations on the different isocyanides allow the prediction of their reactivity towards electron-rich and electron-deficient metal centers by means of the empirical SADAP parameter, which has been derived from the potential energy surface of the electron density on their potentially coordinating carbon atoms

Synthesis of Quinazoline and Quinazolinone Derivatives via Ligand-Promoted Ruthenium-Catalyzed Dehydrogenative and Deaminative Coupling Reaction of 2-Aminophenyl Ketones and 2-Aminobenzamides with Amines

The in situ formed ruthenium catalytic system ([Ru]/L) was found to be highly selective for the dehydrogenative coupling reaction of 2-aminophenyl ketones with amines to form quinazoline products. The deaminative coupling reaction of 2-aminobenzamides with amines led to the efficient formation of quinazolinone products. The catalytic coupling method provides an efficient synthesis of quinazoline and quinazolinone derivatives without using any reactive reagents or forming any toxic byproducts