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Visible light-induced radical umpolung chemistry is utilized to synthesize trifluoromethylated unnatural a-amino acid and amine derivatives. This approach utilizes photoredox catalysis to perform a single-electron-transfer reduction of imines generating a N-centred radical that eventually migrates to the C-centre followed by a radical-radical cross-coupling to deliver reductive trifluoro-methylation products. [ABSTRACT FROM AUTHOR]

Benzylic amine derivatives are ubiquitous structural motifs in organic chemistry. Herein we report a direct synthesis of these compounds via a direct desulfonylative C-arylation of O-tosyl hydroxamates. The applicability of this Ru-catalyzed aminoalkylation is being exemplified by a set of late-stage functionalizations of natural products. [ABSTRACT FROM AUTHOR]

Visible light excitation of iodine(III)–BF3 complex enables the formation of carbocations from C(sp3)–H bonds. The complexes are generated catalytically from iodoarene, carboxylate ligand, the oxidizing agent Selectfluor, and the Lewis acid BF3. This modular catalytic system allows the formation of synthetically valuable amine derivatives without a metal- or photocatalyst. [ABSTRACT FROM AUTHOR]

Two new approaches to the functionalization of the 1-carba-closo-decaborate anion [1-CB9H10]− at boron atoms via the ring-opening of its 1,4-dioxane derivative with various nucleophiles and Pd-catalysed cross-coupling of its iodo derivative with aromatic amines and heteroaromatics were developed. [ABSTRACT FROM AUTHOR]

The Ir-catalyzed enantioselective addition of an N-methyl C–H bond of 2-(methylamino)pyridine derivatives to α-trifluoromethylstyrenes proceeded via C–H activation to give chiral γ-branched amine derivatives having a trifluoromethyl-substituted stereocenter. It was found that a bulky and electron-withdrawing group at the 3-position of 2-(methylamino)pyridines was necessary for the present C–H addition reaction catalyzed by a cationic iridium/chiral bisphosphine complex. [ABSTRACT FROM AUTHOR]

The present study describes the favourable construction of a crystalline covalent organic framework (COF) with exceptional surface area, tunable pore size and huge CO2 capture efficiency to facilitate a novel multicomponent cyclization by introducing CO2 into extremely reactive organic skeletons. In the presence of a catalytic Cu/CuxOy NP-loaded COF, several 2-bromo-3-alkylacrylic acids combined with several amine derivatives and CO2 (0.1 MPa) are converted to the desired oxazolidinediones in excellent yields (up to 96%) under alkali-free conditions and ambient temperature. [ABSTRACT FROM AUTHOR]

The exploration of weak coordinated amine derivative enabled regioselective C–H functionalization remains challenging due to the elusive achievement of reactivity and selectivity simultaneously. Herein, regioselective C–H alkynylation of various readily transformable nitrogen functionalities was developed with great efficiency, with the assistance of the mono-N-protected amino acid (MPAA) ligand via Pd(II) catalysis proceeding via 5, 6 and 7-membered palladacycle intermediates. [ABSTRACT FROM AUTHOR]

The stereoselective synthesis of aminovinyloxazolidinones based on the electrophilic amination of a vinyl-silver intermediate, generated by silver-catalyzed carbon dioxide incorporation on a propargyl amine, was achieved. The geometry of the aminated product was determined by a single crystal X-ray analysis and NOE measurement and it was elucidated that the geometry was proved to be opposite to the geometry predicted from the previous silver-catalyzed carbon dioxide fixation on a propargyl amine derivative. This unexpected stereoselectivity could be successfully explained by a radical mechanism. [ABSTRACT FROM AUTHOR]

Highly efficient Ni-catalyzed asymmetric hydrogenation of cyclic N-sulfonyl ketimino esters was, for the first time, successfully developed, providing various chiral α-monosubstituted α-amino acid derivatives with excellent results (97–99% yields, 90 to >99% ee). Cyclic N-sulfonyl ketimines were also hydrogenated well to afford chiral amine derivatives with 98–99% yields and 97 to >99% ee. The gram-scale asymmetric hydrogenation was performed well with 85% yield and 99% ee using only 0.2 mol% catalyst. [ABSTRACT FROM AUTHOR]

Here we report the use of 2-nitrobenzyl alcohol (NB) as a photoreactive group with amine selectivity and explore its applications for photoaffinity labeling and crosslinking of biomolecules. This work confirms that NB is an efficient photoreactive group and has great potential in drug discovery, chemical biology and protein engineering. [ABSTRACT FROM AUTHOR]

A new radical-mediated intramolecular β-C(sp3)–H amidation reaction of O-alkyl trichloro- or arylimidates is reported. Various oxazolines were efficiently prepared from easily accessible alcohol starting materials. The trichloro-oxazoline products can be hydrolyzed under mild conditions to give valuable 1,2-amino alcohols. This amidation reaction exhibits a broad substrate scope and good functional group tolerance, and offers a powerful means for the C(sp3)–H functionalization of alcohols. Mechanistic studies suggest that a sequence of 1,5-HAT of an imidate radical, iodination and cyclization might be operative. [ABSTRACT FROM AUTHOR]

We report a highly diastereoselective interrupted Ugi reaction to construct a broad range of structurally congested and stereochemically complex spiroindolines from tryptamine-derived isocyanides. The reaction is facilitated by using fluorinated alcohols (TFE or HFIP) as solvents and tolerates a broad range of amines, aldehydes and 2-isocyanoethylindoles to give polycyclic products in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

Sulfamic acid (NH3–SO3) is an acidic zwitterion with many applications. N-Alkylated derivatives are introduced, which can be used as a new class of metal extractants R2NH–SO3 and as new super-acidic ionic liquids [R2NH–SO3H][Tf2N]. The synthesis, properties and novel applications of this versatile platform are discussed. [ABSTRACT FROM AUTHOR]

Light-driven Au(III)-promoted oxidative cleavage of triazole-bearing amine derivatives is utilized for the detection of ionic gold in aqueous media. A bistriazole-bearing boron dipyrromethane (1BODIPY) exhibited selective and sensitive fluorescence enhancement by the addition of Au3+ and subsequent UV irradiation. [ABSTRACT FROM AUTHOR]

The chiral base n-BuLi/(-)-sparteine or n-BuLi/(+)-sparteine surrogate promotes kinetic resolution of N-Boc-2-arylpiperidines by asymmetric deprotonation. The enantioenriched starting material was recovered with yields 39-48% and ers up to 97 : 3. On lithiation then electrophilic quench, 2,2-disubstituted piperidines were obtained with excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

A number of fluorous amphiphilic star block-copolymers containing a tris(benzyltriazolylmethyl)amine motif have been prepared. These polymers assembled into well-defined nanostructures in water, and their mode of assembly could be controlled by changing the composition of the polymer. The polymers were used for enzymeinspired catalysis of alcohol oxidation. [ABSTRACT FROM AUTHOR]

A highly efficient CuBr-catalyzed coupling of ketones, amines and alkynes (KA2) forming propargylic amines bearing a quaternary carbon center with the broadest scope so far has been developed. [ABSTRACT FROM AUTHOR]

Highly regio- and stereoselective remote aziridination of 2,4-dienals has been developed, based on a vinylogous iminium-ion–dienamine catalytic cascade reaction. Transformations of the aziridine products into enantioenriched motifs are also demonstrated. Furthermore, the reaction concept is extended to include enantioselective 1,6-addition of thiols. [ABSTRACT FROM AUTHOR]

The shape of Pd nanocrystals (NCs) can be controlled by combination of oleylamine (OAm) and alkylammonium alkylcarbamate (AAAC), and Pd spheres, tetrahedra and multipods have been synthesized. The multipods and tetrahedra are much more active than the spheres for hydrogenation reactions. [ABSTRACT FROM AUTHOR]

A bis-diphosphine nickel complex with tert-butyl functionalized pendant amines [Ni(PCy 2Nt-Bu 2)2]2+ has been synthesized. It is a highly active electrocatalyst for the oxidation of hydrogen in the presence of base. The turnover rate of 50 s-1 under 1.0 atm H2 at a potential of -0.77 V vs. the ferrocene couple is 5 times faster than the rate reported heretofore for any other synthetic molecular H2 oxidation catalyst. [ABSTRACT FROM AUTHOR]

A long-chain amidoamine derivative (C18AA) acts as a normal organogelator in toluene, but changes to a heat-induced gelator, exhibiting a phase transition from sol to gel on heating upon addition of aqueous LiCl to the toluene gel. The thermal response of the heat-induced gel of C18AA was highly sensitive. [ABSTRACT FROM AUTHOR]

The article offers information on dehydrogenation of amine-boranes with frustrated lewis pair (FLP) which leads to dehydrocoupling products and phosphonium borohydride salts. It includes FLP system as hydrogen storage compounds. It adds that nuclear magnetic resonance spectroscopy analysis is performed for the determination of products.