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Krzysztof Bartkowski Maria Dimitrova Prof. Piotr J. Chmielewski Prof. Dage Sundholm Dr. Miłosz Pawlicki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15477-15482
Understanding of the aromatic properties and magnetically induced current densities of highly conjugated chromophores is important when designing molecules with strongly delocalized electronic structure. Linear extension of the triphyrin(2.1.1) skeleton with an annelated benzo[b]heterocycle fragment modifies the aromatic character by extending the electron delocalization pathway. Two-electron reduction leads to an antiaromatic triphyrin(2.1.1) ring and an aromatic benzo[b]heterocycle subunit. Current-density calculations provide detailed information about the observed pathways and their strengths. 相似文献
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Shaping a Porphyrinoid Frame by Heteroatoms Extrusion: Formation of an Expanded [22]Triphyrin(6.6.0)
Dr. Ewa Pacholska-Dudziak Prof. Dr. Lechosław Latos-Grażyński Dr. Agata Białońska 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(43):10088-10097
An aromatic expanded triphyrin, [22]triphyrin(6.6.0) 2 , containing a pyrrole unit, a bipyrrole moiety, and annulene links, was obtained from a tellurium-containing precursor meso-tetraaryl-26,28-ditellurasapphyrin 1 . The reaction path proceeds through an acid-promoted tellurium extrusion from 1 yielding directly 2 , characterized in a dicationic form by X-ray crystallography. In solution the neutral macrocycle 2 reveals flexibility typical for annulenes and it exists as a mixture of conformers that differ by the configuration of the annulene fragments, as proven by 1H NMR studies and analyzed by DFT methods. The conformation is controlled by protonation state, the nature of an interacting anion, solvent identity, and by interaction with water. 相似文献
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Edwin W. Y. Wong Akito Miura Mathew D. Wright Qi He Prof. Charles J. Walsby Dr. Soji Shimizu Prof. Nagao Kobayashi Prof. Daniel B. Leznoff 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(39):12404-12410
In 1965, gold(II) phthalocyanine (AuPc, 1 ) was described to be synthesized from unsubstituted 1,3‐diiminoisoindoline and gold powder or AuBr. Compound 1 has been regarded as a rare example of a paramagnetic gold(II) complex. However, its chemistry, especially the oxidation state of the central gold ion, has not been previously explored due to the inherent insolubility of 1 caused by its unsubstituted structure. In our attempt to synthesize soluble AuPcs by using 5,6‐di‐substituted 1,3‐diiminoisoindolines, gold(III) phthalocyanine chloride ( 3 ) and a gold(III) complex of an unprecedented ring‐contracted phthalocyanine analogue ([18]tribenzo‐pentaaza‐triphyrin(4,1,1), 4 ) were isolated. With this discrepant result from the original literature in hand, a reinvestigation of the original AuPc synthesis by using unsubstituted 1,3‐diiminoisoindoline and various gold salts (including gold powder and AuBr) was performed, finding that only unsubstituted analogues of 3 and 4 or free‐base phthalocyanine were obtained. No gold(II)‐containing species could be isolated. 相似文献
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Reversible Reduction of Oxatriphyrin(3.1.1)—Adjusting the Coordination Abilities to the Central Ion 下载免费PDF全文
Dr. Miłosz Pawlicki Aneta Kędzia Dominik Bykowski Prof. Lechosław Latos‐Grażyński 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17500-17506
Furan‐fused oxatriphyrin(3.1.1) acts as a ligand towards boron(III), phosphorous(III), and phosphorous(V) ions. The coordination abilities are adjusted by changes of the oxidation state. Two coordination modes are possible, depending on the central‐ion entrapped in the oxatriphyrin(3.1.1) environment. A free base, structurally similar to the complexes, can be easily obtained by regioselective reduction. The resulting molecules are highly emissive after conversion into a phlorin‐like oxatriphyrin(3.1.1) frame (NON donors), and show chiral activity caused by the presence of a tetrahedral carbon. 相似文献
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Dr. Ewa Pacholska-Dudziak Dr. Sandra Hojniak-Thyssen Prof. Dr. Lechosław Latos-Grażyński 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11859-11863
An expanded triphyrin containing a bipyrrole moiety and annulene links, namely tetraphenyl-[22]triphyrin(6.5.0), 2 , has been synthesized. The synthesis proceeded by a postsynthetic transformation of tetraphenyl-[22]triphyrin(6.6.0), 1 , in a metal-free unexpected and unprecedented ring contraction during column chromatography on alumina. The observed transformation, located at the hydrocarbon chain linking the pyrrole units, formally corresponds to a subtraction of one carbon atom from an annulene circuit. In contrast to the flexible substrate 1 , the product 2 is conformationally rigid, and capable of chloride anion binding in its protonated form. 相似文献
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Dr. Aneta Idec Dr. Miłosz Pawlicki Prof. Lechosław Latos-Grażyński 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(1):200-204
Insertion of PCl3 or PhBCl2 into 5,10,15,20-tetraaryl-p-benziporphyrin prompted an intramolecular fusion affording anti-aromatic phosphorus(V) and non-aromatic boron(III) complexes of two N-fused dihydro-p-benziporphyrin isomers. These macrocycles are classified as carbatriphyrin due to the common [CNN] coordination. A sequence of direct transformations, triggered by protonation or two-electron redox processes, afforded a set of three mutually convertible N-fused p-benziporphyrinoids, with distinct anti-aromatic, non-aromatic, and aromatic spectroscopic features. 相似文献
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Dr. Miłosz Pawlicki Karolina Hurej Dr. Ludmiła Szterenberg Prof. Lechosław Latos‐Grażyński 《Angewandte Chemie (International ed. in English)》2014,53(11):2992-2996
Triangularly shaped, contracted porphyrinoids belong to a group of molecules where the geometry significantly modifies the observed electronic properties. The need for a controllable, effective, and widely applicable approach to triphyrins drives extensive research towards macrocyclic materials that act as potential controlling motifs by switching their aromaticity. Two isomeric thiophene‐fused triphyrins(2.1.1) were synthesized by applying an innovative approach. Spectroscopic techniques (NMR, UV/Vis) show that both macrocycles are aromatic and quantitatively convert into anti‐aromatic structures after reduction with a zinc amalgam. The reduced forms were stabilized through boron(III) coordination, thereby allowing the observation of anti‐aromatic 16 π delocalization within a contracted porphyrin. 相似文献
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Porphyrinoid macrocycles are unbreakably linked with the coordination of central cations that drastically influence the observed behavior. A specific place has been recorded for structures where more than one cation is entrapped in a single macrocycle. It has been a characteristic feature of expanded porphyrinoids where the increased coordination space allows a multiple coordination. Because of specific steric confinements, an incorporation of more than one cation within regular or contracted porphyrinoids is more demanding but it can be realized on several ways significantly modifying the observed behavior. We will discuss synthetic strategies leading to structures with increased number of cations and the influence on the observed behavior of such modification. 相似文献
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