Abstract Over the past decade, most significant, conceptual advances in field of fluorination were enabled prominently by organo‐ and transition‐metal catalysis. The challenging transformation remains formation parent CF bond, primarily as a consequence high hydration energy fluoride, strong metal—fluorine bonds, highly polarized bonds to fluorine. Most reactions still lack generality, predictability, cost‐efficiency. Despite all current limitations, modern methods have made fluorinated...

Abstract Die wichtigsten konzeptionellen Fortschritt auf dem Gebiet der Fluorierungen letzten zehn Jahre wurden durch die Organo‐ und Übergangsmetallkatalyse ermöglicht. schwierigste Umwandlung ist weiterhin Bildung C‐F‐Stammbindung, was in erster Linie eine Folge hohen Hydratationsenergie von Fluorid, starker Metall‐Fluor‐Bindungen hoch polarisierten Bindungen zu Fluor ist. Den meisten fehlt es immer noch an Allgemeingültigkeit, Vorhersagbarkeit Kosteneffizienz. Trotz Einschränkungen sind...

The unnatural isotope fluorine-18 ((18)F) is used as a positron emitter in molecular imaging. Currently, many potentially useful (18)F-labeled probe molecules are inaccessible for imaging because no fluorination chemistry available to make them. 110-minute half-life of (18)F requires rapid syntheses which [(18)F]fluoride the preferred source fluorine its practical access and suitable enrichment. However, conventional has been limited nucleophilic reactions. We report development...

Charming fluorine: This Essay examines the recent surge in late-stage fluorination reactions and outlines challenges that need to be overcome increase impact of modern methods on synthesis complex organofluorine compounds. It is outlined how an improved understanding bonding interactions fluoride could lead a new class mild fluorinating reagents range functional-group-tolerant reactions.

ConspectusLate-stage fluorination reactions aim to reduce the synthetic limitations of conventional organofluorine chemistry with respect substrate scope and functional group tolerance. C–F bond formation is commonly thermodynamically favorable but almost universally associated high kinetic barriers. Apart from PhenoFluor chemistry, most modern aromatic methods reported date rely on use transition metal catalysts, bonds often formed through reductive elimination. Reductive elimination make...

The deficiency of robust and practical methods for 18F-radiofluorination is a bottleneck positron emission tomography (PET) tracer development. Here, we report the first transition-metal-assisted 18F-deoxyfluorination phenols. transformation benefits from readily available phenols as starting materials, tolerance moisture ambient atmosphere, large substrate scope, translatability to generate doses appropriate PET imaging.

Abstract The precision with which atoms can be positioned in 3D space through reticular chemistry imbues metal‐organic frameworks (MOFs) the potential to access catalytic performance beyond what is possible classical heterogeneous manifolds. In this paper, we highlight illustrative examples MOF‐based catalysts integrate adsorption and catalysis, optimize cooperation, bypass high‐energy intermediates, bring about active site regeneration, stabilize unusual sites or use extended environment...

New chemistry methods for the synthesis of radiolabeled small molecules have potential to impact clinical positron emission tomography (PET) imaging, if they can be successfully translated. However, progression modern reactions from stage synthetic development preparation radiotracer doses ready use in human PET imaging is challenging and rare. Here we describe process successful translation a palladium-mediated fluorination reaction non-human primate (NHP) baboon imaging-an important...

An alkyl aryl ether bond formation reaction between phenols and primary secondary alcohols with PhenoFluor has been developed. The features a broad substrate scope tolerates many functional groups, substrates that are challenging for more conventional forming processes may be coupled. A preliminary mechanistic study indicates reactivity distinct from formation.

Verzauberndes Fluor: Dieser Essay schildert die jüngsten Erfolge bei Fluorierungen im späten Synthesestadium und identifiziert noch zu nehmenden Hürden zur Etablierung solcher Methoden in der Synthese komplexer Organofluoride. Ansätze werden beschrieben, wie ein vermehrtes Verständnis Bindungswechselwirkungen des Fluors einer neuen Klasse milder vielseitiger Fluorierungsreagentien führen könnte.

Transition-metal-catalyzed cleavage of the Si–H bond in silanes to yield silyl radicals requires substantial amounts energy, which are commonly supplied by photons. For Rh(II) porphyrins, efficient hydrosilylation catalysis becomes accessible only upon site isolation a metal–organic framework (MOF), and formation free likewise irradiation. Within MOF, however, an uncommonly facile direct radical transfer olefin substrates is also possible, makes thermal at room temperature. The ability...

RuNi nanoparticles supported on a metal–organic framework (RuNi@MOF) and formed in situ from ruthenium complex enclosed inside nickel-based MOF act as highly active catalyst for the Guerbet reaction of ethanol to 1-butanol, providing turnover numbers up 725 000 Ru–1. Negligible activity RuNi@MOF upgrading system toward chemically similar 1-butanol makes it possible synthesize competent substrate with >99% selectivity.

Abstract This critical review discusses the synthesis of alcohols via hydrogenation carboxylic acids promoted by heterogeneous metal catalysis. The introductory chapter rationalizes comparative reactivity acid derivatives, which is proceeded a description different mechanisms for hydrogenation. Reaction pathways are discussed that give rise to undesired side products, before comparing classes substrates with focus on biomass‐derived acids. final portion aims guide researchers in selection...

Abstract Rh(II) porphyrin complexes display pronounced metal‐centered radical character and the ability to activate small molecules under mild conditions, but catalysis with porphyrins is extremely rare. In addition facile dimerization, readily engage in kinetically thermodynamically reactions involving two centers generate stable Rh(III)−X intermediates that obstruct turnover thermal catalysis. Here we report site isolation of metalloradicals a MOF host, which not only protects against also...

Metal phosphides have been hailed as potential replacements for scarce noble metal catalysts in many aspects of the hydrogen economy from evolution to selective hydrogenation reactions. But need dangerous and costly phosphorus precursors, limited support dispersion, low stability phosphide surface toward oxidation substantially lower appeal performance catalysis. We show here that a 1-step procedure relies on safe cheap precursors can furnish an air-stable Ni

We report an aromatic C-H hydroxylation protocol in which the arene is activated through η6-coordination to iridium(III) complex. η6-Coordination of increases its electrophilicity and allows for high positional selectivity at site least electron density. Through investigation intermediate η5-cyclohexadienyl adducts exchange reactions, we evaluate incorporation π-activation into a catalytic cycle functionalization.

Abstract An alkyl aryl ether bond formation reaction between phenols and primary secondary alcohols with PhenoFluor has been developed. The features a broad substrate scope tolerates many functional groups, substrates that are challenging for more conventional forming processes may be coupled. A preliminary mechanistic study indicates reactivity distinct from formation.

Radical reactions have recently experienced a resurgence in organic chemistry after many decades of being considered to be too unselective offer viable solution for complex synthetic problems. intermediates often number different reaction pathways available them that are all associated with insubstantial barriers so outcomes can controlled by proximity and dynamics. Cage effects consist the effect surrounding medium, such as solvent or enzyme pocket, on movement radical medium's resulting...

Transition-metal-catalyzed cleavage of the Si–H bond in silanes to yield silyl radicals requires substantial amounts energy, which is commonly supplied by photons. For Rh(II) porphyrins, efficient hydrosilylation catalysis only becomes accessible upon site isolation a MOF, and formation free likewise irradiation. Within however, an uncommonly facile direct radical transfer olefin substrates also possible, makes thermal at room temperature. The ability MOF-supported metalloradicals furnish...

The fine-tuning of metal-phosphine-catalyzed reactions relies largely on accessing ever more precisely tuned phosphine ligands by de-novo synthesis. Late-stage C-H functionalization and diversification commercial phosphines offers rapid access to entire libraries derivatives based privileged scaffolds. But existing routes, relying phosphorus-directed transformations, only yield C