Ascorbic acid (vitamin C) has been used as a radical initiator in metal-free direct C-H arylation of (hetero)arenes. Starting from an aniline, the corresponding arenediazonium ion is generated situ and immediately reduced by vitamin C to aryl that undergoes homolytic aromatic substitution with (hetero)arene. Notably, neither heating nor irradiation required. This procedure mild, operationally simple, constitutes greener approach arylation.

A dynamic nucleophilic aromatic substitution of tetrazines (SN Tz) is presented herein. It combines all the advantages covalent chemistry with versatility tetrazine moiety. Indeed, libraries compounds or sophisticated molecular structures can be easily obtained, which are susceptible to post-functionalization by inverse electron demand Diels-Alder (IEDDA) reaction, also locks exchange. Additionally, obtained disassembled upon application right stimulus, either UV irradiation a suitable...

3-Nitrotyrosine (NT) is generated by the action of peroxynitrite and other reactive nitrogen species (RNS), as a consequence it accumulated in inflammation-associated conditions. This particularly relevant kidney disease, where NT concentration blood considerably high. Therefore, crucial biomarker renal damage, although has been underestimated clinical diagnosis due to lack an appropriate sensing method. Herein we report first fluorescent supramolecular sensor for such compound: Fluorescence...

Ascorbate and catalytic amounts of menadione transform atmospheric oxygen into hydrogen peroxide which is able to carry out oxidation.

Gallic acid is able to catalyse radical C–H arylations of (hetero)arenes with diazonium salts at room temperature in water–acetone. As gallic present multiple bio-wastes, this methodology unleashes an alternative method for waste reutilization.

Good things come in small interactions: The high chiral discrimination displayed by a new receptor with ammonium salts of aromatic α-amino acid methyl esters is mainly the result one weakest noncovalent interactions, CH–π interaction (see picture). has been identified and quantified, its contribution to recognition process evaluated. Detailed facts importance specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made...

We report on the design, synthesis, and operation of a bimetallic molecular biped three-foothold track. The "walker" features palladium(II) complex "foot" that can be selectively stepped between 4-dimethylaminopyridine pyridine ligand sites track via reversible protonation while walker remains attached to throughout by means kinetically inert platinum(II) foot. substitution pattern three binding sites, together with kinetic stability metal-ligand coordination bonds, affords two positional...

We report on the synthesis, structure and properties of [2]rotaxanes prepared by assembly benzylic amide macrocycles around a series sulfide-/sulfoxide-/sulfone-containing threads. The efficacy rotaxane formation is related to hydrogen bond accepting various sulfur-containing functional groups in thread, with highest yields (up 63% rigid vinyl spacer template site) obtained for sulfoxide rotaxanes. X-Ray crystallography rotaxane, 5, shows that macrocycle adopts highly symmetrical chair-like...

Dynamic nucleophilic aromatic substitution of tetrazines (SNTz) has been used for the synthesis dynamic covalent polymer networks that take advantage both reversible nature reaction and versatility tetrazine ring. Polymer microspheres were easily synthesized they proved to be degraded either by UV irradiation or a chemical stimulus, recovering original monomer, which allows an efficient recycling. It was also possible convert one into another (metamorphosis) irreversible exchange monomers....

Abstract Ascorbic acid (vitamin C) has been used as a radical initiator in metal‐free direct CH arylation of (hetero)arenes. Starting from an aniline, the corresponding arenediazonium ion is generated situ and immediately reduced by vitamin C to aryl that undergoes homolytic aromatic substitution with (hetero)arene. Notably, neither heating nor irradiation required. This procedure mild, operationally simple, constitutes greener approach arylation.

Call in the reinforcements: Intra-receptor noncovalent interactions can enantioselectively cooperate with guest binding, thus triggering chiral discrimination. Such cooperativity is described and quantified for a simple synthetic system wherein an intra-receptor hydrogen bond cooperates CH–π interaction exclusively formed D enantiomer of guest, exemplifying reinforced recognition (see picture). Detailed facts importance to specialist readers are published as "Supporting Information"....

Multiple dynamic libraries of compounds are generated when more than one reversible reaction comes into play. Commonly, two or orthogonal reactions used, leading to non-communicating which share no building blocks. Only a few examples communicating have been reported, and in all those cases, blocks reversibly exchanged from library the other, constituting an antiparallel covalent system. Herein we report that communication between different through irreversible process is also possible....

A simple and convenient one-pot protocol for the chemoselective C2-homologation of carbohydrate-derived glycols is described. The method comprises oxidation glycol to corresponding hydroxyaldehyde subsequent Wittig alkenylation. In addition, does not need selective protective group manipulation, it safe, economical, fast (5 6 h), bench-friendly. Its general utility discussed.

Stereochemistry at the metal centre in a Re(I) complex can be modified by manipulating pH: while acidic conditions favour monomeric system, basic induce dimerization which concomitantly epimerizes centre.

The concept of molecular simplification as a drug design strategy to shorten synthetic routes, while keeping or enhancing the biological activity lead drug, has been applied (+)-muconin, an acetogenin with remarkable cytotoxicity. A novel approach that enables stereoselective synthesis such natural compound its enantiomer from common precursor is described. An additional advantage method complete stereochemical control and decrease in number chemical steps required, thus providing...

Abstract Transition metal‐free radical arylation of heteroarenes is achieved at room temperature by simply adding aqueous sodium carbonate to a solution the corresponding heteroarene and arenediazonium salt, which can even be formed in situ. Such an easy, inexpensive mild methodology has been optimized applied expeditious modification interesting molecular cores like naphthylimide or bisthienylcyclopentenes.

Tannins like gallic acid and even grape pomace extract are able to perform oxidations with air thus unleashing an alternative method for reutilization valorization of bio-wastes.

Abstract Cooperativity is one of the most relevant features displayed by biomolecules. Thus, challenges in field supramolecular chemistry to understand mechanisms underlying cooperative binding effects. Traditionally, cooperativity has been related multivalent receptors, but Williams et al. have proposed a different interpretation based on strengthening noncovalent interactions within receptors upon binding. According such an interpretation, positive operates through structural tightening....

An expedient methodology to synthesize macrocyclic compounds in one step based on the Nicholas reaction is disclosed. The key features two intermolecular reactions followed by an intramolecular from starting dicobalt hexacarbonyl–propargylic complex. macrocycles obtained were modified through [2 + 2 2] cycloaddition, generating new C3-symmetric hexasubstituted benzene structures suitable for molecular recognition purposes.

Abstract New pyranoid ε‐sugar amino acids were designed as building blocks, in which the carboxylic acid and amine groups placed positions C2 C3 with respect to tetrahydropyran oxygen atom. By using standard solution‐phase coupling procedures, cyclic homooligomers containing synthesized. Conformation analysis was performed by NMR spectroscopic experiments, FTIR studies, X‐ray analysis, a theoretical conformation search. These studies reveal that presence of methoxy group position C4 pyran...

Schwach, aber nicht unerheblich: Die starke Chiralitätserkennung durch einen neuen Rezeptor für die Ammoniumsalze aromatischer α-Aminosäuremethylester beruht vor allem auf der CH-π-Wechselwirkung, einer schwächsten nichtkovalenten Wechselwirkungen (siehe Bild). Wechselwirkung wurde quantifiziert, und ihr Beitrag zur ermittelt. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents peer-reviewed, but not copy-edited or typeset. They made...

Positive cooperativity between host conformational equilibria and guest binding has been widely reported in protein receptors. However, examples of this kind synthetic hosts are scarce largely serendipitous, among other things because it is hard to envision systems which display cooperativity. In order shed some light on the correlation free binding, selected structural modifications have performed over a family nonpreorganized induce changes analyze their effect affinity. The was evaluated...