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Trifluoroacetates are the most abundant and accessible sources of trifluoromethyl groups, which are key components in pharmaceuticals and agrochemicals. The generation of trifluoromethyl reactive radicals from trifluoroacetates requires their decarboxylation, which is hampered by their high oxidation potential. This constitutes a major challenge for redox‐based methods, because of the need to pair the redox potentials with trifluoroacetate. Here we report a strategy based on iron photocatalysis to promote the direct photodecarboxylation of trifluoroacetates that displays reactivity features that escape from redox limitations. Our synthetic design has enabled the use of trifluoroacetates for the trifluoromethylation of more easily oxidizable organic substrates, offering new opportunities for late‐stage derivatization campaigns using chemical feedstocks, Earth‐abundant catalysts, and visible‐light. [ABSTRACT FROM AUTHOR]

A photoinduced carboxylation of alkyl halides with CO2 at remote sp3 C−H sites enabled by the merger of photoredox and Ni catalysis is described. This protocol features a predictable reactivity and site selectivity that can be modulated by the ligand backbone. Preliminary studies reinforce a rationale based on a dynamic displacement of the catalyst throughout the alkyl side chain. [ABSTRACT FROM AUTHOR]

A Pd-catalyzed C(sp3)--H functionalization/ carbenoid insertion is described. The method allows for the rapid synthesis of bicyclic frameworks, generating all-carbon quaternary centers via multiple C--C bond formations in a straightforward manner. [ABSTRACT FROM AUTHOR]

The complex [Pd( O, N, C-L)(OAc)], in which L is a monoanionic pincer ligand derived from 2,6-diacetylpyridine, reacts with 2-iodobenzoic acid at room temperature to afford the very stable pair of PdIV complexes (OC-6-54)- and (OC-6-26)-[Pd( O, N, C-L)( O, C-C6H4CO2-2)I] (1.5:1 molar ratio, at −55 °C). These complexes and the PdII species [Pd( O, N, C-L)(OX)] and [Pd( O, N, C-L′)(NCMe)]ClO4, (X=MeC(O) or ClO3, L′=another monoanionic pincer ligand derived from 2,6-diacetylpyridine), are precatalysts for the arylation of CH2CHR (RCO2Me, CO2Et, Ph) using IC6H4CO2H-2 and AgClO4. These catalytic reactions have been studied and a tentative mechanism is proposed. The presence of two PdIV complexes was detected by ESI(+)-MS during the catalytic process. All the data obtained strongly support a PdII/PdIV catalytic cycle. [ABSTRACT FROM AUTHOR]

The complex [Pd(O1,N1,C1-L)(OClO3)](L = monoanionic ligand resulting from deprotonation of the acetylgroup of the dimethyl monoketal of 2,6-diacetylpyridine) reacts withneutral ligands L1(phosphines, isocyanides, CO, N-donorligands) to give the complexes [Pd(O1,N1,C1-L)L1]ClO4, [Pd(N1,C1-L)L12]ClO4, and [Pd(C1-L)L13]ClO4. The complex [Pd(N1,C1-L)(pda)]ClO4(pda = NH2C6H4NH2-2) can be used as a catalyst for thesynthesis of 2′,2′,4′-trimethyl-2′,3′-dihydro-1H-1′,5′-benzodiazepine (Bzdiaz) from pda andacetone. The intermediate [Pd(O1,N1,C1-L)(Bzdiaz)]ClO4has been isolated from an acetone solution of [Pd(N1,C1-L)(pda)]ClO4. The ligand L in some of the above complexes hydrolyzes togive [Pd(O1,N1,C1-L′)L1]ClO4(L′ = monoanionic ligand resulting from the deprotonationof one acetyl group of 2,6-diacetylpyridine, L1= MeCN, tBuNC). These complexes are best preparedby reacting L1with [Pd(O1,N1,C1-L′)(NCMe)]ClO4, which, in turn, can be obtained from 2,6-diacetylpyridiniumperchlorate and Pd(OAc)2in MeCN. When THF is used as solvent,[Pd(O1,N1,C1-L′)(OH2)]ClO4can be isolated. The crystal structures of [Pd(O1,N1,C1-L′)(NCMe)]ClO4and [Pd(O1,N1,C1-L)(CNXy)]ClO4have been determined. [ABSTRACT FROM AUTHOR]

Blockieren und steuern: Die Titelreaktion ermöglicht die effektive Sulfonierung und Alkylierung von Arenen mit dirigierenden Substituenten. Das Substrat wird zunächst in ortho ‐ Stellung metalliert, sodass im gebildeten Intermediat die C ‐ M ‐ Bindung nicht weiter funktionalisiert werden kann. Stattdessen wirkt der Ruthenium ‐ Katalysator als effizienter Elektronendonor, der den elektrophilen Angriff fernsteuert (siehe Schema). [ABSTRACT FROM AUTHOR]

Remote control: The title reaction is effective for the sulfonation and alkylation of arenes bearing directing groups. Initial ortho metalation of the substrate forms an intermediate which does not evolve towards functionalization at the CM bond. Instead, the ruthenium catalyst acts as a strong electron‐donating group, thus directing a remote electrophilic attack. [ABSTRACT FROM AUTHOR]

A photoinduced carboxylation of alkyl halides with CO 2 at remote sp 3 C-H sites enabled by the merger of photoredox and Ni catalysis is described. This protocol features a predictable reactivity and site selectivity that can be modulated by the ligand backbone. Preliminary studies reinforce a rationale based on a dynamic displacement of the catalyst throughout the alkyl side chain., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Driven by the inherent synthetic potential of CO 2 as an abundant, inexpensive and renewable C 1 chemical feedstock, the recent years have witnessed renewed interest in devising catalytic CO 2 fixations into organic matter. Although the formation of C-C bonds via catalytic CO 2 fixation remained rather limited for a long period of time, a close look into the recent literature data indicates that catalytic carboxylation reactions have entered a new era of exponential growth, evolving into a mature discipline that allows for streamlining the synthesis of carboxylic acids, building blocks of utmost relevance in industrial endeavors. These strategies have generally proven broadly applicability and convenient to perform. However, substantial challenges still need to be addressed reinforcing the need to cover metal-catalyzed carboxylation area in a conceptual and concise manner, delineating the underlying new principles that are slowly emerging in this vibrant area of expertise., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A catalytic protocol that reliably predicts and controls the site-selective incorporation of CO 2 to a wide range of unsaturated hydrocarbons utilizing water as formal hydride source is described. This platform unlocks an opportunity to catalytically repurpose three abundant, orthogonal feedstocks under mild conditions.

The first catalytic intermolecular proximal C1-C2 cleavage of benzocyclobutenones (BCB) without prior carbonyl activation or employing noble metals has been developed. This protocol operates at room temperature and is characterized by an exquisite chemo-, regio- and diastereoselectivity profile, constituting a unique platform for preparing an array of elusive carbocyclic skeletons., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Remote control: The title reaction is effective for the sulfonation and alkylation of arenes bearing directing groups. Initial ortho metalation of the substrate forms an intermediate which does not evolve towards functionalization at the CM bond. Instead, the ruthenium catalyst acts as a strong electron-donating group, thus directing a remote electrophilic attack., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The complex [Pd(O,N,C-L)(OAc)], in which L is a monoanionic pincer ligand derived from 2,6-diacetylpyridine, reacts with 2-iodobenzoic acid at room temperature to afford the very stable pair of Pd(IV) complexes (OC-6-54)- and (OC-6-26)-[Pd(O,N,C-L)(O,C-C(6)H(4)CO(2)-2)I] (1.5:1 molar ratio, at -55 °C). These complexes and the Pd(II) species [Pd(O,N,C-L)(OX)] and [Pd(O,N,C-L')(NCMe)]ClO(4), (X = MeC(O) or ClO(3), L' = another monoanionic pincer ligand derived from 2,6-diacetylpyridine), are precatalysts for the arylation of CH(2)=CHR (R = CO(2)Me, CO(2)Et, Ph) using IC(6)H(4)CO(2)H-2 and AgClO(4). These catalytic reactions have been studied and a tentative mechanism is proposed. The presence of two Pd(IV) complexes was detected by ESI(+)-MS during the catalytic process. All the data obtained strongly support a Pd(II)/Pd(IV) catalytic cycle., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)