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Alkylamines form the backbone of countless nitrogen‐containing small molecules possessing desirable biological properties. Despite advances in amine synthesis through transition metal catalysis and photoredox chemistry, multicomponent reactions that leverage inexpensive materials to transform abundant chemical feedstocks into three‐dimensional α‐substituted alkylamines bearing complex substitution patterns remain scarce. Here, we report the design of a catalyst‐free electroreductive manifold that merges amines, carbonyl compounds and carbon‐based radical acceptors under ambient conditions without rigorous exclusion of air and moisture. Key to this aminative carbofunctionalization process is the chemoselective generation of nucleophilic α‐amino radical intermediates that readily couple with electrophilic partners, providing straightforward access to architecturally intricate alkylamines and drug‐like scaffolds which are inaccessible by conventional means. [ABSTRACT FROM AUTHOR]

In this article we report that a cationic version of Akiba's BiIII complex catalyzes the reduction of amides to amines using silane as hydride donor. The catalytic system features low catalyst loadings and mild conditions, en route to secondary and tertiary aryl‐ and alkylamines. The system tolerates functional groups such as alkene, ester, nitrile, furan and thiophene. Kinetic studies on the reaction mechanism result in the identification of a reaction network with an important product inhibition that is in agreement with the experimental reaction profiles. [ABSTRACT FROM AUTHOR]

Catalytic carbonylations of aryl electrophiles via C(sp2)−N cleavage remains a significant challenge. Herein, we demonstrate an aminocarbonylation of aniline‐derived trialkylammonium salts promoted by visible light with a simple cobalt catalyst. The reaction proceeds under mild conditions suitable for late‐stage functionalization and is amenable to telescoped carbonylations directly from anilines. A range of alkylamines are successful partners, and alkoxycarbonylation is also demonstrated. Mechanistic studies and DFT calculations support a novel mechanism for catalytic carbonylations of aryl electrophiles involving a key visible light‐induced carbonyl photodissociation. [ABSTRACT FROM AUTHOR]

Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel‐catalyzed switchable site‐selective alkene hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate. This protocol allows the convenient synthesis of α‐ and β‐branched protected amines, both of which are important to the fields of pharmaceutical chemistry and biochemistry. In addition, enantioenriched β‐branched alkylamines can be accessed in a catalytic asymmetric variant. Preliminary mechanistic studies indicate that the formation of a more stable nickelacycle provides the driving force of migration. The thermodynamic and kinetic properties of different reduction elimination intermediates are responsible for the switchable site‐selectivity. [ABSTRACT FROM AUTHOR]

Regio‐ and enantioselective hydroarylamination, hydroalkylamination and hydroamidation of styrenes have been developed by NiH catalysis with a simple bioxazoline ligand under mild conditions. A wide range of enantioenriched benzylic arylamines, alkylamines and amides can be easily accessed by nitroarenes, hydroxylamines and dioxazolones, respectively as amination reagents. The chiral induction in these reactions is proposed to proceed through an enantiodifferentiating syn‐hydronickellation step. [ABSTRACT FROM AUTHOR]

α‐Aminosilanes are an important class of organic compounds that show biological activity. In this communication, a new approach to α‐aminosilanes that utilizes photoredox catalysis to enable three‐component coupling of organo(tristrimethylsilyl)silanes with feedstock alkylamines and aldehydes is presented. A wide range of highly functionalized α‐aminosilanes can be obtained in good yields under mild conditions. Both primary amines and secondary amines are compatible with this transformation. Moreover, optically pure α‐aminosilanes are accessible by using chiral amines. Mechanistic studies indicate that reactions proceed through radical/radical cross‐coupling of silyl radicals with α‐amino alkyl radicals. [ABSTRACT FROM AUTHOR]

The first cationic titanium catalyst system for the intermolecular hydroaminoalkylation of alkenes with various tertiary alkylamines is presented. Corresponding reactions which involve the addition of the α‐C−H bond of a tertiary amine across the C−C double bond of an alkene take place at temperatures close to room temperature with excellent regioselectivity to deliver the branched products exclusively. Interestingly, for selected amines, α‐C−H bond activation occurs not only at N‐methyl but also at N‐methylene groups. [ABSTRACT FROM AUTHOR]

Secondary and tertiary alkylamines are privileged substance classes that are often found in pharmaceuticals and other biologically active small molecules. Herein, we report their direct synthesis from alkenes through an aminative difunctionalization reaction enabled by iron catalysis. A family of ten novel hydroxylamine‐derived aminating reagents were designed for the installation of several medicinally relevant amine groups, such as methylamine, morpholine and piperazine, through the aminochlorination of alkenes. The method has excellent functional group tolerance and a broad scope of alkenes was converted to the corresponding products, including several drug‐like molecules. Besides aminochlorination, the installation of other functionalities through aminoazidation, aminohydroxylation and even intramolecular carboamination reactions, was demonstrated, further highlighting the broad potential of these new reagents for the discovery of novel amination reactions. [ABSTRACT FROM AUTHOR]

Vicinal diamines are ubiquitous materials in organic and medicinal chemistry. The direct coupling of olefins and amines would be an ideal approach to construct these motifs. However, alkene diamination remains a long‐standing challenge in organic synthesis, especially when using two different amine components. We report a general strategy for the direct and selective assembly of vicinal 1,2‐diamines using readily available olefin and amine building blocks. This mild and straightforward approach involves in situ formation and photoinduced activation of N‐chloroamines to give aminium radicals that enable efficient alkene aminochlorination. Owing to the ambiphilic nature of the β‐chloroamines produced, conversion into tetra‐alkyl aziridinium ions was possible, thus enabling diamination by regioselective ring‐opening with primary or secondary amines. This strategy streamlines the preparation of vicinal diamines from multistep sequences to a single chemical transformation. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of a new class of functional silver nanoclusters (AgNCs) capped with pillar[5]arene (P5)‐based host ligands. These NCs are readily prepared through direct synthesis or ligand exchange synthesis and are stable at room temperature for over 4 months. The pillar[5]arene‐stabilized NCs (Ag29(LA‐P5)12(TPP)2) endorse reversible host–guest interactions with neutral alkylamines and cationic quaternary ammonium guests. This results in the formation of spherical assemblies with unparalleled changes in their optical properties including an astonishing circa 2000‐fold luminescence enhancement. This is the highest luminescence enhancement ratio reported so far for such atomically precise NCs. Our synthetic protocol paves the way for the preparation of a new generation of metal nanoclusters protected by macrocyclic ligands with molecular recognition and selectivity toward specific guests. [ABSTRACT FROM AUTHOR]

Reported is the discovery of an approach to functionalize secondary alkylamines using 2‐halobenzoic acids as aryl‐transfer reagents. These reagents promote an unusually mild carboxylate‐assisted oxidative addition to alkylamine‐derived palladacycles. In the presence of AgI salts, a decarboxylative C(sp3)−C(sp2) bond reductive elimination leads to γ‐aryl secondary alkylamines and renders the carboxylate motif a traceless directing group. Stoichiometric mechanistic studies were effectively translated to a Pd‐catalyzed γ‐C(sp3)−H arylation process for secondary alkylamines. [ABSTRACT FROM AUTHOR]

We demonstrate that the devised incorporation of an alkylamine group into the second coordination sphere of an FeII complex allows to switch its reactivity with H2O2 from the usual formation of FeIII species towards the selective generation of an FeIV‐oxo intermediate. The FeIV‐oxo species was characterized by UV/Vis absorption and Mössbauer spectroscopy. Variable‐temperature kinetic analyses point towards a mechanism in which the heterolytic cleavage of the O−O bond is triggered by a proton transfer from the proximal to the distal oxygen atom in the FeII‐H2O2 complex with the assistance of the pendant amine. DFT studies reveal that this heterolytic cleavage is actually initiated by an homolytic O−O cleavage immediately followed by a proton‐coupled electron transfer (PCET) that leads to the formation of the FeIV‐oxo and release of water through a concerted mechanism. Don't cleave me this way: A novel synthetic iron(II) complex bearing a second sphere intra‐molecular base efficiently forms an iron(IV)‐oxido species in the presence of H2O2 rather than the usual formation of an FeIII species. Mechanistic studies demonstrate an overall heterolytic cleavage of the O−O bond proceeding by a homolytic cleavage with a concerted proton coupled electron transfer (PCET). [ABSTRACT FROM AUTHOR]

An efficient method for the metal‐free deaminative borylation of alkylamines, using bis(catecholato)diboron as the boron source, to directly synthesize various alkyl potassium trifluoroborate salts is introduced. The key to this high reactivity is the utilization of pyridinium salt activated alkylamines, with a catalytic amount of a bipyridine‐type Lewis base as a promoter. This transformation shows good functional‐group compatibility (e.g. it is unimpeded by the presence of a ketone, indole, internal alkene, or unactivated alkyl chloride) and can serve as a powerful synthetic tool for borylation of amine groups in complex compounds. Mechanistic experiments and computations suggest a mechanism in which the Lewis base activated B2cat2 unit intercepts an alkyl radical generated by single‐electron transfer (SET) from a boron‐based reductant. N to B: A mild catalytic system was developed for the preparation of alkyl potassium trifluoroborate salts by C−N bond cleavage. This method has good functional‐group compatibility and can serve as a powerful synthetic tool for late‐stage borylative cleavage of C−N bonds in complex compounds. dtbpy=4,4′‐di‐tert‐butyl‐2,2′‐bipyridine. [ABSTRACT FROM AUTHOR]

Abstract: Reported is an achiral CpxRhIII/chiral carboxylic acid catalyzed asymmetric C−H alkylation of diarylmethanamines with a diazomalonate, followed by cyclization and decarboxylation to afford 1,4‐dihydroisoquinolin‐3(2H)‐one. Secondary alkylamines as well as nonprotected primary alkylamines underwent the transformation with high enantioselectivities (up to 98.5:1.5 e.r.) by using a newly developed chiral carboxylic acid as the sole source of chirality to achieve enantioselective C−H cleavage by a concerted metalation‐deprotonation mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Mitochondrial membrane potential is more negative in cancer cells than in normal cells, allowing cancer targeting by delocalized lipophilic cations (DLCs). However, as the difference is rather small, these drugs affect also normal cells. Now a concept of pro‐DLCs is proposed based on an N‐alkylaminoferrocene structure. These prodrugs are activated by the reaction with reactive oxygen species (ROS) forming ferrocenium‐based DLCs. Since ROS are overproduced in cancer, the high‐efficiency cancer‐cell‐specific targeting of mitochondria could be achieved as demonstrated by fluorescence microscopy in combination with two fluorogenic pro‐DLCs in vitro and in vivo. We prepared a conjugate of another pro‐DLC with a clinically approved drug carboplatin and confirmed that its accumulation in mitochondria was higher than that of the free drug. This was reflected in the substantially higher anticancer effect of the conjugate. [ABSTRACT FROM AUTHOR]

There are several reports on the synthesis of alkylamines, but most of the reported methods are not suitable for the synthesis of hindered amines. In this research, we found that a copper catalyst is effective for the formation of congested C−N bonds at room temperature. Control experiments revealed that a copper amide is a key intermediate. Moreover, when a chiral amine was used, a quaternary carbon stereogenic center was created with good selectivity. [ABSTRACT FROM AUTHOR]

Selective bromination of γ-methylene C(sp3)−H bonds of aliphatic amides and δ-methylene C(sp3)−H bonds of nosyl-protected alkyl amines are developed using NBS as the brominating reagent and catalytic amount of CuII/phenanthroline complexes as the catalyst. Aryl and benzylic C−H bonds at other locations remain intact during this directed radical abstraction reaction. [ABSTRACT FROM AUTHOR]

The development of chemically modified mRNA holds great promise as a new class of biologic therapeutics. However, the intracellular delivery and endosomal escape of mRNA encapsulated in nanoparticles has not been systematically investigated. Here, we synthesized a diverse set of cationic polymers and lipids from a series of oligoalkylamines and subsequently characterized their mRNA delivery capability. Notably, a structure with an alternating alkyl chain length between amines showed the highest transfection efficiency, which was linked to a high buffering capacity in a narrow range of pH 6.2 to 6.5. Variation in only one methylene group resulted in enhanced mRNA delivery to both the murine liver as well as porcine lungs after systemic or aerosol administration, respectively. These findings reveal a novel fundamental structure-activity relationship for the delivery of mRNA that is independent of the class of mRNA carrier and define a promising new path of exploration in the field of mRNA therapeutics. [ABSTRACT FROM AUTHOR]

A highly adaptable method targeting the ubiquitous and very important pyrrolizidine and indolizidine scaffolds is presented. The general synthetic utility of the method is underscored by its application to the rapid and easy synthesis of five natural products starting from readily accessible alkylfuran precursors. These unprotected primary furylalkylamines are subjected to photooxygenation conditions, which initiate a complex cascade reaction sequence concluding with the production of high value motifs. This sequence can be tailored to need by varying the choice of both photosensitizer and base additive. [ABSTRACT FROM AUTHOR]

The efficient o-carboryne precursor 1-Li-2-OTf- o-C2B10H10 reacts with lithium amides at room temperature to give a series of N-carboranyl amines in moderate to high isolated yields. This reaction is compatible with a broad substrate scope from primary to secondary, alkyl to aryl amines. The reaction mechanism is also proposed on the basis of experimental results and DFT calculations. This represents the first general and efficient method for the synthesis of 1-NR1R2- o-carboranes. [ABSTRACT FROM AUTHOR]

A photoactivated neutral organic super electron donor cleaves challenging arenesulfonamides derived from dialkylamines at room temperature. It also cleaves a) ArCNR and b) ArNC bonds. This study also highlights the assistance given to these cleavage reactions by the groups attached to N in (a) and to C in (b), by lowering LUMO energies and by stabilizing the products of fragmentation. [ABSTRACT FROM AUTHOR]

What size plate do you want? Semiconducting and plasmonic copper phosphide platelets with sizes tunable from the nanometer to the micrometer scale have been developed, and their photoresponse and photovoltaic activity studied. The size control was achieved by controlling the nucleation density of materials in the reaction system. [ABSTRACT FROM AUTHOR]