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Angewandte Chemie, Wiley, Vol. 134, No. 7 ( 2022-02-07)

The cyclohexene motif is ubiquitous in nature and specialty chemicals. A straightforward selective access to chiral cyclohexenes from unactivated dienes and dienophiles is not feasible by classical Diels–Alder reaction and constitutes an unsolved synthetic challenge. We report a mild and enantioselective iron‐catalyzed cross‐[4+2]‐cycloaddition of unactivated dienes providing access to chiral 1,3‐substituted vinyl‐cyclohexenes. The development of bis ‐dihydroisoquinoline ligands was vital to obtain iron complexes that display high reactivities and excellent chemo‐, regio‐ and enantioselectivities towards the targeted cyclohexenes. A range of diene substrates is well accommodated including feedstocks like butadiene, isoprene and myrcene. The structures of different iron complexes are mapped by X‐ray crystallographic analysis and linked to their performance.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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Angewandte Chemie, Wiley, Vol. 134, No. 2 ( 2022-01-10)

Covalent organic frameworks (COFs) hold great potentials for addressing the challenge of highly efficient oil–water separation, but they are restricted by the poor wettability and processability as crystalline membranes. Here we report the design and synthesis of two‐dimensional (2D) robust COFs with controllable hydrophobicity and processability, allowing the COF layers to be directly grown on the support surfaces. Three 2D COFs with AA or ABC stacking are prepared by condensation of triamines with fluorine and/or isopropyl groups and perfluorodialdehyde. They all show excellent tolerance to water, acid, and base, with water contact angles (CA) of 111.5–145.8°. The two COFs with isopropyl and fluorine mixtures can grow as a coating on a stainless‐steel net (SSN) substrate, whereas the one with only fluorine substituents cannot. The superhydrophobic COF@SSN coating with water CA of up to 150.1° displays high water‐resistance and self‐cleaning properties, enabling high oil–water separation performances with an efficiency of over 99.5 % and a permeation flux of 2.84×10 5  L m −2  h −1 , which are among the highest values reported for state‐of‐the‐art membranes.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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physica status solidi (b), Wiley, Vol. 21, No. 2 ( 1967), p. K97-K98

Online Resource

0370-1972, 1521-3951

German

Wiley

1967

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 8 ( 2022-02-14)

Framework nucleic acids (FNAs) represent nanoscale oligonucleotide assemblies with unique physical, chemical, and biological properties that are different from their building blocks. Following simple Watson–Crick base‐pairing rules, arbitrary DNA frameworks with diverse shapes, sizes, and dimensions can be prepared with high reproducibility and stability. The programmable assembly of nucleic acids into FNAs presents a highly controllable model for studies on nano–bio interactions and allows scrutiny of “nanostructure‐activity relationships.” Herein, we present an overview of recent progress with FNAs in the hope of deepening our understanding of nano–bio interfacing. We summarize the biological profiles and immune responses of various FNAs as functions of their shape, sizes, and surface charges. We then highlight recent efforts to apply FNAs for biomedical applications and discuss the challenges of FNAs for potential clinical translation. We believe that this Minireview can bring up‐to‐date information on FNAs and shed light on how their design may be harnessed for selective biomedical applications.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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Angewandte Chemie, Wiley, Vol. 133, No. 46 ( 2021-11-08), p. 24541-24554

Online Resource

0044-8249, 1521-3757

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Wiley

2021

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Angewandte Chemie, Wiley, Vol. 134, No. 2 ( 2022-01-10)

Accurately regulating the selectivity of the oxygen reduction reaction (ORR) is crucial to renewable energy storage and utilization, but challenging. A flexible alteration of ORR pathways on atomically dispersed Zn sites towards high selectivity ORR can be achieved by tailoring the coordination environment of the catalytic centers. The atomically dispersed Zn catalysts with unique O‐ and C‐coordination structure (ZnO 3 C) or N‐coordination structure (ZnN 4 ) can be prepared by varying the functional groups of corresponding MOF precursors. The coordination environment of as‐prepared atomically dispersed Zn catalysts was confirmed by X‐ray absorption fine structure (XAFs). Notably, the ZnN 4 catalyst processes a 4 e − ORR pathway to generate H 2 O. However, controllably tailoring the coordination environment of atomically dispersed Zn sites, ZnO 3 C catalyst processes a 2 e − ORR pathway to generate H 2 O 2 with a near zero overpotential and high selectivity in 0.1 M KOH. Calculations reveal that decreased electron density around Zn in ZnO 3 C lowers the d‐band center of Zn, thus changing the intermediate adsorption and contributing to the high selectivity towards 2 e − ORR.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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physica status solidi (b), Wiley, Vol. 21, No. 2 ( 1967), p. K111-K113

Online Resource

0370-1972, 1521-3951

German

Wiley

1967

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 21, No. 2 ( 1967), p. K127-K130

Online Resource

0370-1972, 1521-3951

German

Wiley

1967

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 3 ( 2022-01-17)

A modular approach to substituted cyclobutylboronic esters is described. It proceeds by successive intermolecular radical additions of xanthates to pinacolato 1‐cyclobutenylboronate and to pinacolato bicyclo[1.1.0]but‐1‐ylboronate. Success hinges on tuning the stability of the α‐boryl radical by exploiting the stabilizing influence of the trivalent boronic ester and the slightly destabilizing cyclobutane, which increases the σ‐character of the radical. Reductive removal of the xanthate group finally provides a range of 1,2‐ and 1,3‐disubstituted cyclobutylboronic esters. The contrast with cyclopropylboronic esters is striking, since the strong destabilization by the highly strained cyclopropane ring allows the first radical addition to take place but not the second. Furthermore, the first adducts are geminal xanthyl boronic esters that can be converted into cyclobutanones. This chemistry furnishes cyclobutylboronic esters that would be quite difficult to obtain otherwise and thus complements existing methods.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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physica status solidi (b), Wiley, Vol. 21, No. 2 ( 1967), p. K167-K169

Online Resource

0370-1972, 1521-3951

German

Wiley

1967

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1481096-7

Physica Status Solidi (b), Wiley, Vol. 27, No. 2 ( 1968), p. fmi-fmi

Online Resource

0370-1972, 1521-3951

German

Wiley

1968

208851-4

1481096-7

Physica Status Solidi (b), Wiley, Vol. 28, No. 1 ( 1968), p. 39-44

Online Resource

0370-1972, 1521-3951

German

Wiley

1968

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1481096-7

Physica Status Solidi (b), Wiley, Vol. 28, No. 1 ( 1968), p. 45-60

Online Resource

0370-1972, 1521-3951

German

Wiley

1968

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1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 1 ( 2022-01-03)

Spectacular progress has recently been achieved in transition metal‐catalyzed C−H borylation of phosphines as well as directed electrophilic C−H borylation. As shown here, P‐directed electrophilic borylation provides a new, straightforward, and efficient access to phosphine–boranes. It operates under metal‐free conditions and leverages simple, readily available substrates. It is applicable to a broad range of backbones (naphthyl, biphenyl, N ‐phenylpyrrole, binaphthyl, benzyl, naphthylmethyl) and gives facile access to various substitution patterns at boron (by varying the boron electrophile or post‐derivatizing the borane moiety). NMR monitoring supports the involvement of P‐stabilized borenium cations as key intermediates. DFT calculations reveal the existence and stabilizing effect of π‐arene/boron interactions in the (biphenyl)( i ‐Pr) 2 P→BBr 2 + species.

Online Resource

0044-8249, 1521-3757

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Wiley

2022

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physica status solidi (b), Wiley, Vol. 27, No. 1 ( 1968-01), p. 57-67

Es werden die Reflexionsspektren von GeSi‐Legierungen im Spektralbereich 1 bis 13 eV bei Zimmertemperatur und im Bereich 1 bis 6 eV bei der Temperatur des flüssigen Stickstoffs gemessen. In diesem Spektralbereich wird auch die Dielektrizitätskonstante ϵ 1 + i ϵ 2 berechnet. Die Kurven ergeben die Abhängigkeit der ϵ 2 ‐Spektren von der Zusammensetzung der Legierungen und zeigen Änderungen der Energiebandstruktur in einigen kritischen Punkten.

Online Resource

0370-1972, 1521-3951

English

Wiley

1968

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Angewandte Chemie, Wiley, Vol. 134, No. 1 ( 2022-01-03)

Ibrutinib ist ein Inhibitor der Bruton‐Tyrosinkinase, der für die Behandlung von Patienten mit chronischer lymphatischer Leukämie, Mantelzell‐Lymphom und Waldenström‐Makroglobulinämie zugelassen und mit Nebenwirkungen verbunden ist. Um seine Toxizität zu minimieren, haben wir Ibrutinib mit einem zellgerichteten, internalisierenden Antikörper verbunden. Dazu synthetisierten wir ein polyanionisches Derivat, Ibrutinib‐Cy3.5, das seine volle Funktionalität beibehält. Dieser anionische Inhibitor wird durch unser Anti‐CD20‐Protamin‐Targeting‐Konjugat und freies Protamin komplexiert und assembliert dadurch spontan zu einem elektrostatisch stabilisierten vesikulären Nanoträger. Die Komplexierung führte zu einer Akkumulation des Wirkstoffs, der durch die CD20‐Antigen‐Internalisierung in die Zellen aufgenommen und in seiner Wirksamkeit verstärkt wurde. In vivo beobachteten wir eine signifikante Anreicherung des Wirkstoffs in Xenotransplantat‐Lymphom‐Tumoren bei Mäusen mit defizientem Immunsystem und eine signifikant verbesserte Reaktion auf niedrigere Dosen im Vergleich zum ursprünglichen Wirkstoff.

Online Resource

0044-8249, 1521-3757

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Wiley

2022

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Angewandte Chemie, Wiley, Vol. 133, No. 50 ( 2021-12-06), p. 26615-26615

Online Resource

0044-8249, 1521-3757

English

Wiley

2021

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Physica Status Solidi (b), Wiley, Vol. 28, No. 1 ( 1968), p. 111-119

Online Resource

0370-1972, 1521-3951

German

Wiley

1968

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 4 ( 2022-01-21)

Disclosed here is a dual copper and nickel catalytic system with a silyl hydride source for promoting the linear selective hydroalkylation of vinylarenes. This carbon–carbon bond‐forming protocol is applied to couple a variety of functionalized vinylarenes with alkyl halides applying a nickel(II) NNN pincer complex in the presence of an NHC‐ligated copper catalyst. This combination allows for a 1 mol % loading of the nickel catalyst leading to turnover numbers of up to 72. Over 40 examples are presented, including applications for pharmaceutical diversification. Labeling experiments demonstrated the regioselectivity of the reaction and revealed that the copper catalyst plays a crucial role in enhancing the rate for formation of the reactive linear alkyl nickel complex. Overall, the presented work provides a complimentary approach for hydroalkylation reactions, whilst providing a preliminary mechanistic understanding of the cooperativity between the copper and nickel complexes.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

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Physica Status Solidi (b), Wiley, Vol. 26, No. 2 ( 1968), p. 453-460

Online Resource

0370-1972, 1521-3951

German

Wiley

1968

208851-4

1481096-7