A widely applicable triazole‐substituted chiral aryl iodide is described as catalyst for enantioselective oxidation reactions. The introduction of a substituent in ortho‐position to the iodide is key for its high reactivity and selectivity. Besides a robust and modular synthesis, the main advantage of this catalyst is the excellent performance in a plethora of mechanistically diverse enantioselective transformations, such as spirocyclizations, phenol dearomatizations, α‐oxygenations, and oxidative rearrangements. DFT‐calculations of in situ generated [hydroxy(tosyloxy)iodo]arene isomers give an initial rational for the observed reactivity.

We report the application of a chiral triazole-substituted iodoarene in a direct enantioselective hydroxylation of alkyl arenes. This method allows the rapid synthesis of chiral benzyl alcohols in high yields and exceptional stereocontrol despite its non-templated nature. In a unique cascade activation comprising of an initial irradiation-induced radical C-Hbromination and a consecutive enantioconvergent hydroxylation, the iodoarene catalyst has a dual role. It initiates the radical bromination in its oxidized state through an in situ formed bromoiodane and in the second, Cu-catalyzed step, it acts as a chiral ligand. To the best of our knowledge this the first example demonstrating the ability of a chiral aryl iodide catalyst acting both, as an oxidant and as a chiral ligand in a highly enantioselective C-H-activating transformation. Furthermore, this is the first example for an enantioconvergent hydroxylation. zylic C-H-bond in the presence tertiary C-H-bonds was observed. This unique reaction cascade offers great potential for other enantioselective oxidative benzylic C-H-activations, although the mechanism of the enantioconvergent step still needs to be further elaborated. ASSOCIATED CONTENTSupporting Information. The Supporting Information is available free of charge on the ACS Publications website at DOI: XXX. Including all experimental procedures and characterization data.

Aw idely applicable triazole-substituted chiral aryl iodide is described as catalyst for enantioselective oxidation reactions.The introduction of asubstituent in ortho-position to the iodide is key for its high reactivity and selectivity.B esides ar obust and modular synthesis,t he main advantage of this catalyst is the excellent performance in ap lethora of mechanistically diverse enantioselective transformations,s uch as spirocyclizations,p henol dearomatizations, a-oxygenations, and oxidative rearrangements.D FT-calculations of in situ generated [hydroxy(tosyloxy)iodo]arene isomers give an initial rational for the observed reactivity.Hypervalentiodinecompoundsareversatileoxidantswhich have been utilized with great success in aplethora of oxidative coupling reactions [1] and in natural product synthesis. [2] In related enantioselective processes,achiral aryl iodide precursor can be used in catalytic amounts in combination with aterminal co-oxidant to generate achiral hypervalent iodine compound in situ. This chiral oxidant is subsequently capable of transferring its chirality onto the desired coupling products through diastereotopic transition states in the key oxidative C-X bond forming step. [3] Since the discovery of the first enantioselective transformation catalyzed by ac hiral aryl iodide in 2007 by Wirth and co-workers, [4] more than ad ozen highly diverse C1-and C2-symmetric chiral aryl iodides have been developed. [5] Successful catalysts,s uch as 1-4 ( Figure 1), usually show ag ood reactivity and selectivity in only one distinct class of oxidative transformation. So far there is no omnipotent chiral aryl iodide available that performs well throughout the most important oxidative transformations and hence can be seen as broadly applicable catalyst for iodane-based enantioselective couplings.Our group is heavily interested in the development of N-heterocycle-stabilized iodanes (NHIs) as an ew class of stable and at the same time highly reactive hypervalent iodine compounds. [6, 7] With the aim to design novel chiral aryl iodides which are robust to synthesize in amodular sequence and show ag ood performance throughout adiverse range of enantioselective oxidations,w erecently developed the novel triazole-substituted aryl iodide 5 ( Figure 2) and evaluated its reactivity in the Kita-spirocyclization of 1-naphthols. [8] Even though this "first-generation" catalyst gave the so far highest enantioselectivities in direct comparison to other C1-symmetric aryl iodides for this reaction, reactivities were low.W ell-established C2-symmetric aryl iodides,s uch as spirobiindanes developed by Kita or resorcinol ethers 1 developed by Uyanik and Ishihara, showed significantly higher stereoinduction and yielded the desired chiral lactones in better yields. [9] Due to the promising initial results with catalyst 5 and its highly modular and robust synthesis,w e further developed "second-generation" triazole catalysts 6 ( Figure 2) bearing as imple ortho-modification at the aryl iodide.W et herefore synthesized orth...

Objective: To evaluate the knowledge, believes, psychological and behavioural impact of COVID-19 on the general population in the Middle East, exploring how it impacted public lives. Methods: A descriptive cross-sectional online survey was sent to a convenience sample in the Middle East through social media (Facebook and WhatsApp) between 16th of June and 30th of June 2020. The questionnaire was designed to collect the demographic, participant’s source of information regarding COVID-19, knowledge and believes about COVID-19, the psychological consequences of COVID-19, impact of COVID-19 on participant’s behaviour. The final version of the questionnaire was further tested for content validity by experts in the field. Results: A total of 2,061 participants completed the survey, with the majority being females (n=1394, 67.6%), from urban areas (n=1896, 92%) and the majority were from countries of The Levant (n=1199, 58.1%), followed by the Arabian Peninsula (n=392, 19.1%), Iraq (n=300, 14.6%) and Egypt (n=138, 6.7%). Few participants (3.0%) reported to have been infected and many (n=1847, 89.6%) were committed to quarantine at home. Social media platforms were the most common sources of information (41.2%). Many (63%) believed that COVID-19 is a biological weapon and were afraid of visiting crowded places (85%). The majority avoided public facilities (86.9%) such as prayer places and believed that the news about COVID-19 made them anxious (49.5%).

This study presents an enantioselective oxidative cyclization of N-allyl carboxamides via a chiral triazole-substituted iodoarene catalyst. The method allows the synthesis of highly enantioenriched oxazolines and oxazines, with yields of up to 94% and enantioselectivities of up to 98% ee. Quaternary stereo centers can be constructed and, besides N-allyl amides, the corresponding thioamides and imideamides are well tolerated as substrates, giving rise to a plethora of chiral 5-membered N-heterocycles. By applying a multitude of further functionalizations, we finally demonstrate the high value of the observed chiral heterocycles as strategic intermediates for the synthesis of other enantioenriched target structures.sustaining the stereochemistry (92% ee). 71 Lastly, we prepared 3-aminopropane-1,2-diol by a reduction of 3a followed by acid-mediated ring-opening to give the amino diol 4g. Since this compound could not be analyzed by HPLC, it was directly transformed into the N-tosylated derivative 4h. 4h was isolated in 42% yield but with a diminished selectivity of 78% ee .In summary, we have established a practical method for the enantioselective oxidative cyclization of N-allyl amides by using an improved triazole-substituted iodoarene catalyst. This method is characterized by a broad substrate scope which allows the construction of highly enantioenriched 5-oxazolines, thiazolines, and imidazolines. Quaternary stereocenters can be constructed with high efficiency as well and the method was further extended to oxazines. Many of the constructed compounds can serve as chiral building blocks for the synthesis of interesting chiral target structures. This was demonstrated in a variety of further functionalizations, in particular of the terminal OH group.In further investigations, we aim to apply C1-symmetric triazole-based iodoarenes in similar oxidative cyclizations to generate other useful 5-and 6-membered heterocycles. Additionally, cascade reactions in which the reactive hypervalent iodine intermediate is trapped directly by nucleophiles other than OH will also be part of future investigations. ASSOCIATED CONTENTSupporting Information. All supporting information is available free of charge on the ACS Publications website at DOI: XXX. This includes all experimental procedures and characterization data.

The structure of in situ generated chiral arylλ 3 -iodanes obtained under oxidative reaction conditions was not yet observable with experimental techniques and their proposed structures are purely based on DFT calculations. Herein, we establish vibrational circular dichroism (VCD) spectroscopy as an experimental technique to verify DFT-calculated chiral iodane structures. Based on a chiral triazole-substituted iodoarene catalyst, we were able to elucidate a yet undescribed cationic chiral iodane as the most populated intermediate under oxidative conditions with a significant intramolecular NÀ I-interaction and no significant interactions with tosylate or m-chlorobenzoic acid as potential anionic ligands. Instead, aggregation of these substrates was found, which resulted in the formation of a noncoordinating anionic hydrogen bonded complex. The importance of VCD as a crucial experimental observable is further highlighted by the fact that our initial structural proposal, that was purely based on DFT calculations, could be falsified.

A catalytic highly enantioselective synthesis of spirooxazolines is presented. Starting from readily available 2-naphthol-substituted benzamides and using catalytic amounts of a chiral triazole-substituted iodoarene catalyst, a variety of spirooxazolines can...

Exploration of three-dimensional structural space has become crucial for the development of novel bioactive molecules. In this context, polar spirocycles have emerged as key scaffolds due to their enhanced 3D character and well-defined spatial orientation. Herein, we report the development of a highly modular strategy to access beta-spirocyclic pyrrolidine derivatives from readily available starting materials, i.e., cyclic ketones and amino or oxamic acids. The sequence proceeds through a straightforward Knoevenagel condensation, followed by a domino Giese-type reaction/base-mediated cyclisation process, delivering a broad scope of polar spirocyclic scaffolds in good to excellent yields. The products can be readily diversified to access a wider range of spirocyclic cores (such as lactams or succinimides), thus increasing the versatility of our method to gain rapid access to libraries of potential drug-like molecules.