Rhodium(III)-Catalyzed Redox-Neutral Synthesis of Isoquinolinium Salts via C–H Activation of Imines
作者:Miaomiao Tian、Guangfan Zheng、Xuesen Fan、Xingwei Li
DOI:10.1021/acs.joc.8b00758
日期:2018.6.15
Redox-neutral synthesis of isoquinolinium salts via C–H activation of presynthesized or in situ formed imines and coupling with α-diazo ketoesters has been realized, where a zinc salt promotes cyclization as well as provides a counteranion. Under three-component conditions, both ketone and aldehydes are viable arene sources. The coupling of imines with diazo malonates under similar conditions afforded
Radical Changes in Lewis Acid Catalysis: Matching Metal and Substrate
作者:Tim Bleith、Qing-Hai Deng、Hubert Wadepohl、Lutz H. Gade
DOI:10.1002/anie.201603072
日期:2016.6.27
stereochemical rigidity of the coordination sphere of boxmi/CuII catalysts is key to achieving high enantioselectivity in the electrophilic alkylation of β‐ketoesters, this pathway is outperformed by a radical process for the corresponding catalytic transformation of oxindoles, giving rise to racemic products. For the corresponding ZnII catalysts, the selectivity in the latter process is outstanding despite
尽管boxmi / Cu II催化剂的配位域的立体化学刚度是在β-酮酸酯的亲电烷基化中实现高对映选择性的关键,但该途径却被相应的羟吲哚催化转化的自由基过程所超越,产生了外消旋产物。对于相应的Zn II催化剂,尽管配位壳具有更大的可塑性,但后者的选择性却非常出色。因此,该反应发展成为一种高度有用的合成方法,该方法能够以高收率和对映选择性转化多种底物。
A Zn
<sub>4</sub>
L
<sub>6</sub>
Capsule with Enhanced Catalytic C−C Bond Formation Activity upon C
<sub>60</sub>
Binding
作者:Zhenpin Lu、Roy Lavendomme、Olaf Burghaus、Jonathan R. Nitschke
DOI:10.1002/anie.201903286
日期:2019.7
naphthalenediimide (NDI) motifs. Its reduction lent these NDI panels persistent radical anion character. The redox activity of this cage allows it to act as a catalyst for the oxidative coupling of different tetraaryl borates to give biaryls. The catalyticactivity of the cage was enhanced following its binding of C60, which implies a mechanism that does not involve encapsulation of the substrate.
合成了可氧化还原的自组装Zn II 4 L 6笼,其中包含萘二甲酰亚胺(NDI)图案。它的还原使这些NDI面板具有持久的自由基阴离子特性。该笼的氧化还原活性使其能够充当催化剂,用于将不同的四芳基硼酸酯氧化偶联以生成联芳基。笼子与C 60结合后,其催化活性得到增强,这暗示了不涉及底物包封的机理。
Formation of ionic liquids of divalent metal complexes comprising N‑alkylethylenediamines and the solvation of the nickel(II) complexes
作者:Haruka Yasuda、Chisayo Nakayama、Masayasu Iida
DOI:10.1016/j.molliq.2018.07.124
日期:2018.11
A series of divalent N‑alkylethylenediamine (alkyl‑en) metal(II) (alkyl = hexyl, 2‑ethylhexyl, octyl, dodecyl; metal = Ni, Cu, and Zn) complexes was prepared and their phase behavior was studied using differential scanning calorimetry. This kind of metalcomplexes is very useful for systematically investigating the relationship between phase behavior and molecular structures. It was found that several
Improved Acid Resistance of a Metal–Organic Cage Enables Cargo Release and Exchange between Hosts
作者:Lin Xu、Dawei Zhang、Tanya K. Ronson、Jonathan R. Nitschke
DOI:10.1002/anie.202001059
日期:2020.5.4
vertices. The acid stability of 1 was found to be greater than that of the analogous tetrahedron 2 built from 2-formylpyridine. Intriguingly, the peripheral presence of additional pyridine rings in 1 resulted in distinct guest binding behavior from that of 2, affecting guest scope as well as binding affinities. The different stabilities and guest affinities of capsules 1 and 2 enabled the design of