Advances in mercury(II)-salt-mediated cyclization reactions of unsaturated bonds

The synthesis of complex cyclic compounds is extremely challenging for organic chemists. Many transition-metal-salt-mediated cyclizations are reported in literature. Hg(II) salts have been successfully employed in cyclizations to form complex heterocyclic and carbocyclic structures that are impossible to synthesize with other transition metal salts. In this review, we have summarized cyclization reactions that are performed with Hg(II) salts. These salts are also successfully applied in stoichiometric or catalytic amounts to form complex cyclic structures and natural products.

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Effect of Shale Ash-Based Catalyst on the Pyrolysis of Fushun Oil Shale

Catalysts ◽

10.3390/catal9110900 ◽

2019 ◽

Vol 9 (11) ◽

pp. 900

Author(s):

Hao Lu ◽

Fengrui Jia ◽

Chuang Guo ◽

Haodan Pan ◽

Xu Long ◽

...

Keyword(s):

Activation Energy ◽

Transition Metal ◽

Oil Shale ◽

Metal Salt ◽

Metal Salts ◽

Aliphatic Hydrocarbons ◽

Shale Oil ◽

Transition Metal Salt ◽

Transition Metal Salts ◽

Shale Ash

The effect of shale ash (SA)-based catalysts (SA as carriers to support several transition metal salts, such as ZnCl2, NiCl2·6H2O, and CuCl2·2H2O) on oil shale (OS) pyrolysis was studied. Results showed that SA promoted OS pyrolysis, and the optimum weight ratio of OS:SA was found to be 2:1. The SA-supported transition metal salt catalyst promoted the OS pyrolysis, and the catalytic effect increased with increasing load of the transition metal salt within 0.1–3.0 wt%. The transition metal salts loaded on the SA not only promoted OS pyrolysis and reduced the activation energy required but also changed the yield of pyrolysis products (reduced shale oil and semi-coke yields and increased gas and loss yield). SA-supported 3 wt% CuCl2·2H2O catalyst not only exhibited the highest ability to reduce the activation energy in OS pyrolysis (32.84 kJ/mol) but also improved the gas and loss yield, which was 4.4% higher than the uncatalyzed reaction. The supporting transition metal salts on the SA also increased the content of short-chain hydrocarbons in aliphatic hydrocarbons in shale oil and catalyzed the aromatization of aliphatic hydrocarbons to form aromatic hydrocarbons. The catalytic activity of the transition metal salt on the SA-based catalyst for OS pyrolysis decreased in the order of CuCl2·2H2O > NiCl2·6H2O > ZnCl2.

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Electrical Conduction in Transition-Metal Salts

Zeitschrift für Naturforschung A ◽

10.1515/zna-2015-0538 ◽

2016 ◽

Vol 71 (4) ◽

pp. 311-314

Author(s):

M.A. Grado-Caffaro ◽

M. Grado-Caffaro

Keyword(s):

Transition Metal ◽

Metal Salt ◽

Electrical Conductance ◽

Wave Functions ◽

Metal Salts ◽

Electrical Conductor ◽

Electron Wave ◽

Transition Metal Salt ◽

Mathematical Expressions ◽

Transition Metal Salts

AbstractWe predict that a given transition-metal salt as, for example, a K2CuCl4·2H2O–type compound, can behave as an electrical conductor in the paramagnetic case. In fact, we determine the electrical conductance in a salt of this type. This conductance is found to be quantised in agreement with previous well-known results. Related mathematical expressions in the context of superexchange interaction are obtained. In addition, we determine the corresponding (macroscopically viewed) current density and the associated electron wave functions.

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Tripod-type 2,2′-bipyridine ligand for lanthanide cations: synthesis and photophysical studies on coordination to transition metal cations

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0485 ◽

2018 ◽

Vol 96 (4) ◽

pp. 419-424 ◽

Cited By ~ 1

Author(s):

Dmitry S. Kopchuk ◽

Grigory A. Kim ◽

Igor S. Kovalev ◽

Sougata Santra ◽

Grigory V. Zyryanov ◽

...

Keyword(s):

Transition Metal ◽

Metal Salt ◽

Metal Cations ◽

Europium Complex ◽

Metal Salts ◽

Published Data ◽

Transition Metal Cations ◽

Transition Metal Salts ◽

Lanthanide Cations ◽

Bipyridine Ligand

New tripod-type 2,2′-bipyridine ligand consisting of a central polyaminocarboxylic moiety for the coordination to lanthanide cations and three appended 5-phenyl-2,2′-bipyridine fragments for the coordination to various transition metal cations have been prepared. A europium complex of this ligand was prepared, and its photophysical properties and a luminescent response towards transition metal salts (particularly, CdI2, Cd(OAc)2, Zn(ClO4)2, Cu(OAc)2, and HgCl2) have been studied. Europium cation luminescence quenching in the presence of transition metal salts in solution was observed in all cases. In addition, it was observed that the fluorescent response of the europium complex was quite individual depending on the type of the metal salt. The obtained data were compared with the earlier published data for some lanthanide complexes bearing additional sites for the chelation of transition metal cations.

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