A metal-free C–H oxidation for the construction of allylic esters has been developed. The use a commercially available and inexpensive catalyst oxidant, readily starting materials, coupled with operational simplicity reaction, renders methodology useful alternative to other approaches typically employed in synthesis esters.

A highly water soluble 3:2 complex of copper(II) and 2,4,6-tris(di-2-pyridylamine)-1,3,5-triazine (TDAT) has been synthesized structurally characterized. The crystallized in a triclinic P1 space group with molecular formula [Cu3(TDAT)2Cl3]Cl3·2H2O (1), where each copper ion is coordinated by four pyridine nitrogen atoms an apical chloride. trinuclear stable at physiological relevant conditions. It can bind to DNA through electrostatic attraction cleave efficiently the supercoiled pBR322 into...

A mild and rapid approach has been developed for the construction of fully substituted pyrazoles using TBAI as a catalyst TBHP an oxidant, in which tosylhydrazide functions ring component sulfonyl precursor. This protocol features wide substrate scope with broad range functional group tolerance, utilizes easily available starting materials, can be scaled-up, is operationally simple.

A metal-free oxidative coupling of methyl ketones and primary or secondary amines to α-ketoamides has been developed. Four intermediates, α-iodoketone, α-aminoketone, iminium intermediate, α-hydroxy amine have identified through a series control experiments. The atom-economic methodology can be scaled-up, tolerates variety functional groups, is operationally simple.

A novel trinuclear copper(II) complex, Cu3-L (L = N,N,N',N',N' ',N' '-hexakis(2-pyridyl)-1,3,5-tris(aminomethyl)benzene), exhibited efficient oxidative strand scission of plasmid DNA. The solution behavior the complex has been studied by potentiometric titration, UV spectroscopy, and cyclic voltammetry. data showed that there are three redox-active copper ions in with types bound water. demonstrated a moderate binding ability for readily cleaves DNA presence ascorbate to give nicked (form...

A preorganized cleft dinuclear zinc(II) complex of 2,6-bis(1-methyl-1,4,7-triazacyclonon-1-yl)pyridine 1 as an artificial nuclease was prepared via improved method. The interactions 1, 2 [1,4,7-triazacyclononane (TACN)], and their complexes with calf thymus DNA were studied by spectroscopic techniques, including fluorescence CD spectroscopy. results indicate that the binding affinities these compounds are in following order: ZnII2−1 > ZnII−2 2. constants 3.57 × 106 1.43 105 M−1,...

Abstract Novel 1,7‐dioxa‐4,10‐diazacyclododecane artificial receptors with two pendant aminoethyl ( 3 ) or guanidinoethyl 4 side arms have been synthesized. Spectroscopy, including fluorescence and CD spectroscopy, of the interactions , their copper(II) complexes calf thymus DNA indicated that binding affinity these compounds follows order Cu 2+ – >Cu > constants are 7.2×10 8.7×10 M −1 respectively. Assessment by agarose gel electrophoresis plasmid pUC 19 cleavage activity in presence...

Through merging Cu-based carbenes in a radical process, novel crossover reaction has been successfully established, leading to the facile and efficient syntheses of various γ-peroxy esters 1,4-dicarbonyl compounds. Considering that both carbene complexes radicals are extremely reactive, therefore exist only extraordinarily low concentrations, high selectivity this coupling is unusual.

We herein report the palladium(II)-catalyzed bromination and iodination of a variety α-hydrogen-containing carboxylic acid amino acid-derived amides. These reactions are exclusively enabled by quinoline-type ligands. The halogenated products obtained in this reaction highly versatile rapidly undergo further diversification. Further, we first example free acid-directed Pd(II)-catalyzed C(sp3)–H bromination, quinoline

A ruthenium-catalyzed highly chemoselective N-alkylation of 2-pyridones has been developed, affording N-alkylated 2-pyridone derivatives in good yields and excellent N-selectivity. The key to achieve this unprecedented N–H rather than O–H insertion reaction is the use CpRu(PPh3)2Cl as catalyst sulfoxonium ylides alkylation reagents. Moreover, protocol also amenable 7-azaindoles by slightly varying conditions. Furthermore, sulfonium are suitable reagents, providing selectivity.

A standardized protocol enabling rapid NMR data collection for high-quality protein structure determination is presented that allows one to capitalize on high spectrometer sensitivity: a set of five G-matrix Fourier transform experiments resonance assignment based highly resolved 4D and 5D spectral information acquired in conjunction with single simultaneous 3D 15 N, 13 C aliphatic , aromatic -resolved [ 1 H, H]-NOESY spectrum providing H- H upper distance limit constraints. The was...

The Cu-catalyzed three-component reaction between quinolines, diazo compounds, and alkenes has been established for direct construction of indolizine derivatives via quinolinium ylides. This methodology is distinguished by the use a commercially inexpensive catalyst readily available starting materials, wide substrate scope, operational simplicity.

A new cross-coupling reaction between sulfonyl hydrazides and diazo compounds has been established, leading to a variety of β-carbonyl sulfones in good yields. This methodology was distinguished by simple manipulation, easily available starting materials, wide substrate scope. plausible mechanism involving radical process proposed based upon the experimental observations literature.

Abstract Asymmetric carbene insertion reactions represent one of the most important protocols to construct carbon–heteroatom bonds. The use donor–acceptor diazo compounds bearing an ester group is however a prerequisite for achieving high enantioselectivity. Herein, we report chemo‐ and enantioselective formal N−H 2‐pyridones that has been accomplished first time with enynones as donor–donor precursors. DFT calculations indicate unprecedented 1,4‐proton transfer from O C. rhodium catalyst...

By using diazonaphthoquinones and anilines as key reagents through a point-to-axis chiral transfer strategy, the atroposelective synthesis via asymmetric C(sp2 )-H bond insertion reaction of arenes has been realized under rhodium catalysis, providing resulting biaryl atropisomers in moderate to excellent yields with good enantiomeric ratios (up 99:1). Further elaboration indicates this type axially scaffold may have promising potentials developing novel ligands.

A highly efficient rhodium-catalyzed formal C-H insertion reaction between indoles and 1-diazonaphthoquinones has been established, providing a novel protocol for the atroposelective synthesis of axially chiral C2-arylindoles (up to 99:1 er) under mild conditions. Typically, only 1 mol % Rh2(S-PTTL)4 is used chelation group not needed this conversion.

A novel strategy for the difunctionalization of styrenes was developed. This synthesis includes use electrophilic perfluoroalkyl and tert-butylperoxy radicals produces (1-(tert-butylperoxy)-2-perfluoroalkyl)ethylbenzene at room temperature, which has been traditionally difficult to synthesize. With least four radical species included in transformation, its high chemoselectivity extraordinary; results were further elucidated using computational studies. The methodology also holds a good...

A catalyst-controlled selective functionalization of indoles with vinyl diazoacetates has been developed. The use gold catalysts exclusively leads to C3-alkylation products, whereas the highly diastereoselective cyclopropanation reaction is dominant for silver catalysis. Importantly, and vinylcarbenes exhibit carbenic rather than vinylogous reactivity in these transformations.

The unprecedented dearomative migratory rearrangement reactions of 2-oxypyridines with N-sulfonyl-1,2,3-triazoles have been developed under rhodium catalysis, providing a reliable and efficient protocol for accessing N-substituted 2-pyridones. These two distinct rearrangements feature the controllable 1,4-migration carbonate group from O-to-C as well O-to-N 1,6-migration an acyl via α-imino carbene transfer. Moreover, reaction pyridotriazoles delivers products in high efficiency.

The asymmetric synthesis of β2,2 -amino acids remains a formidable challenge in organic synthesis. Here novel organocatalytic enantioselective aminomethylation ketenes with stable and readily available N,O-acetals is reported, providing esters bearing an all-carbon quaternary stereogenic center high enantiomeric ratios catalytic amount chiral phosphoric acid. Typically, this transformation probably proceeds through counter-anion-directed catalysis. As result, concise, practical,...

An enantioselective insertion of a carbene into the Csp2-H bond anisole derivatives has been accomplished using an achiral gold complex and chiral phosphoric acid as catalytic system, providing novel protocol for synthesis α,α-diaryl acetates. Density functional theory calculations reveal reactivity origin enantioselectivity this reaction.

Here we report the first example of iridium-catalyzed asymmetric