A series of structurally differentiated α‐cationic phospholes containing cyclopropenium, imidazolium and iminium substituents has been synthesized by reaction of chlorophosphole 1 with the corresponding stable carbenes. Evaluation of the donor properties of these compounds reveals that their strong π‐acceptor character is heavily influenced by the nature of the cationic group. The coordination chemistry of these newly prepared ligands towards Au(I) centers is also described and their unique electronic...
Thu Aug 27, 2020 11:04
Fluorinated organophosphorus(V) compounds are a very versatile class of compounds, but the synthetic methods available to make them bear the disadvantages of 1) occasional handling of toxic or pyrophoric P(III) starting materials and 2) a dependence on hazardous fluorinating reagents such as XeF 2 . Herein, we present a simple solution and introduce a deoxygenative fluorination (DOF) approach that utilizes easy‐to‐handle phosphine oxides as starting materials and effectively replaces harsh fluorinating...
Thu Aug 27, 2020 18:33
Semiconductor quantum dots (QDs) have attracted tremendous attention in the field of photocatalysis, owing to their superior optoelectronic properties for photocatalytic reactions, including high absorption coefficients and long photogenerated carrier lifetimes. Herein, by choosing 2‐(3,4‐dimethoxyphenyl)‐3‐oxobutanenitrile as a model substrate, we demonstrate that the stereoselective (>99%) C–C oxidative coupling reaction can be realized with a high product yield (99%) using zwitterionic‐capped...
Thu Aug 27, 2020 18:05
Graphite has become a critical material because of its high supply risk and essential applications in energy industries. Its present synthesis still relies on an energy‐intensive thermal treatment pathway (Acheson process) at ~3,000 o C. Herein, a mechanochemical approach is demonstrated to afford highly crystalline graphite nanosheets at ambient temperature. The essence of our methodology lies in the successive decomposition and rearrangement of a carbon nitride framework driven by a denitriding...
Thu Aug 27, 2020 17:05
NMR spectroscopy offers unique benefits for ligand binding studies on isotopically labelled target proteins, such as atomic resolution, direct distinction of binding sites and modes, lowest detectable affinity limit, and function independent setup. Yet, retracing protein signal assignments from apo to holo states to derive exact dissociation constants and Chemical Shift Perturbation amplitudes (for ligand docking and structure‐based optimization) requires lengthy titration series of 2D heteronuclear...
Thu Aug 27, 2020 15:12
Molecular imprinting technique and dynamic covalent chemistry were implemented to achieve quantitative one‐pot syntheses of homochiral helical cages inside aromatic foldamers. One‐handed helical cages P‐1, M‐1, P‐2 and M‐2 were assembled from their precursors in the presence of appropriate templates (d‐, l‐tartaric acid, d‐ and l‐sorbitol, respectively) via three sequential steps in one pot: imine‐linked chain elongation, template‐induced folding and [4+2] cycloaddition between helical turns. These...
Thu Aug 27, 2020 13:36
The transfer of charges through double helical DNA is a very well investigated bioelectric phenomenon. RNA, on the contrary, has been less studied in this regard. The few available data report on charge transfer through RNA duplex structures mainly composed of homonucleotide sequences. In the light of RNA world scenarios, it is an interesting question, if charge transfer can be coupled with RNA function. Functional RNAs however, contain versatile structural motifs. Therefore, electron transport also...
Thu Aug 27, 2020 12:58
The innate hypoxic microenvironment of most solid tumors has a major influence on tumor growth, invasiveness and distant metastasis. Here, hypoxia‐activated self‐immolative paclitaxel prodrug (PTX 2 ‐Azo) was synthesized and combined with photodynamic therapy (PDT) to prepare light‐boosted PTX nanoparticle (Ce6/PTX 2 ‐Azo NP) by encapsulation PTX 2 ‐Azo into photosensitizer chlorine (Ce6) decorated peptide copolymer. In this nanoparticle, PTX 2 ‐Azo prevents unexpected premature drug leakage...
Thu Aug 27, 2020 12:33
Most metallo‐supramolecular assemblies of low nuclearity adopt simple topologies, with bridging ligands spanning neighboring metal centers in a direct fashion. Here we contribute a new structural motif to the family of host compounds with low metal count (two) that consists of a pair of doubly‐interlocked, figure‐eight‐shaped subunits, also termed “lemniscates”. Each metal is chelated by two chiral bidentate ligands, composed of a peptidic macrocycle that resembles a natural product with two pyridyl‐terminated...
Wed Aug 26, 2020 22:00
A palladium‐catalyzed intermolecular asymmetric dearomatization of 3‐arylindoles with internal alkynes was developed with the use of achiral Xantphos and chiral sulfinamide phosphine ligand (PC‐Phos) as the co‐ligands. This method could deliver various spiro[indene‐1,3'‐indole] compounds in good yields (up to 95% yield) with up to 98% e e . The salient features of the transformation include the use of readily available substrates, ease of scale‐up and the versatile functionalization of the...
Wed Aug 26, 2020 21:28
The paramagnetic NMR toolbox of 1D and 2D NMR techniques now enables in depth structural analysis of paramagnetic mononuclear complexes and metal–organic cages comparable to that of diamagnetic analogues. The robustness and broad versatility of the toolbox is demonstrated by the characterisation of CoII and high spin FeII mononuclear complexes and a CoII 4L6 cage. Abstract The large paramagnetic shifts and short relaxation times resulting from the presence of a paramagnetic centre complicate...
Wed Aug 26, 2020 20:55
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