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1.
Qizhao Li Masatoshi Ishida Hiroto Kai Tingting Gu Chengjie Li Xin Li Glib Baryshnikov Xu Liang Weihua Zhu Hans gren Hiroyuki Furuta Yongshu Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):5986-5990
A hybrid thia‐norhexaphyrin comprising a directly linked N‐confused pyrrole and thiophene unit ( 1 ) revealed unique macrocycle transformations to afford multiply inner‐annulated aromatic macrocycles. Oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone triggered a cleavage of the C?S bond of the thiophene unit, accompanied with skeletal rearrangement to afford unique π‐conjugated products: a thiopyrrolo‐pentaphyrin embedded with a pyrrolo[1,2]isothiazole ( 2 ), a sulfur‐free pentaphyrin incorporating an indolizine moiety ( 3 ), and a thiopyranyltriphyrinoid containing a 2H‐thiopyran unit ( 4 ). Furthermore, 2 underwent desulfurization reactions to afford a fused pentaphyrin containing a pyrrolizine moiety ( 5 ) under mild conditions. Using expanded porphyrin scaffolds, oxidative thiophene cleavage and desulfurization of the hitherto unknown N‐confused core‐modified macrocycles would be a practical approach for developing unique polypyrrolic aromatic macrocycles. 相似文献
2.
Diazadibora[1.1.1.1]m,p,m,p‐cyclophanes: Ambipolar Conjugated Macrocycles with Different B–π–N Embedded Patterns 下载免费PDF全文
Dr. Akihiro Ito Masashi Uebe Dr. Ryohei Kurata Soichiro Yano Dr. Hiroyuki Fueno Dr. Takashi Matsumoto 《化学:亚洲杂志》2018,13(7):754-760
Are different B(boron)–π–N(nitrogen) embedded patterns to bring about significant different (opto)electronic properties for the same macrocyclic molecular backbone? A series of B–π–N‐embedded alternate‐meta‐para‐linked cyclophanes 1 – 3 have been prepared and characterized as a new class of ambipolar π‐conjugated B–π–N macrocycles. The answer to the opening question is yes. These macrocycles revealed the intramolecular charge transfer in the oxidized states and the intriguing photophysical proprerties in accordance with the embedded patterns, suggesting the electronic structures are tunable by introducing multiple B–π–N moieties. 相似文献
3.
Burcak Icli Dr. Euro Solari Dr. Benan Kilbas Dr. Rosario Scopelliti Prof. Kay Severin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(46):14867-14874
Multicomponent reactions between 1,4‐benzenediboronic acid, catechol, and different pyridyl ligands are reported. The condensation of 1,4‐benzenediboronic acid with catechol gives 1,4‐bis(benzodioxaborole)benzene. Upon crystallization, the ester aggregates with the N‐donor ligands through dative B? N bonds. Depending on the nature of the pyridyl ligand, molecularly defined macrocycles or polymeric structures are obtained. 1D polymers are formed with 4,4‐bipyridine and 1,2‐di(4‐pyridyl)ethylene, whereas a 2D network is obtained with the tetradentate ligand tetra(4‐pyridylphenyl)ethylene. These results highlight the utility of dative B? N bonds in structural supramolecular chemistry and crystal engineering. 相似文献
4.
Tobias Becherer Denys Meshcheryakov Andreas Springer Volker Böhmer Christoph A. Schalley 《Journal of mass spectrometry : JMS》2009,44(9):1338-1347
Two series, one of tris‐urea macrocycles and another of hexakis‐urea macrocycles, are examined by (tandem) Fourier‐transform ion cyclotron resonance (FTICR) mass spectrometry with respect to their fragmentation patterns and anion binding properties. All macrocycles are based on two different building blocks, one of which is a very rigid xanthene unit and the other one is a more flexible diphenyl ether. The composition and the sequence of these units thus determine their flexibility. During the fragmentation of deprotonated oligourea macrocycles in the gas phase, one urea N? CO bond is cleaved followed by a scrambling reaction within the macrocycle structure. Consequently, fragments are observed that deviate from those that would be expected from the sequence of the subunits. Interesting anion binding properties involve the simultaneous recognition of two chloride anions by one of the hexakis‐urea macrocycles, whose flexibility allows this host to form a double‐helical structure. Flexibility also determines which of the hexameric receptors bears a high sulfate affinity. The interaction energy between some of the macrocycles and sulfate is high enough to even stabilize the intrinsically unstable sulfate dianion. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
Dmitri V. Konarev Salavat S. Khasanov Mikhail K. Islyaikin Akihiro Otsuka Hideki Yamochi Hiroshi Kitagawa Rimma N. Lyubovskaya Evgenii N. Ivanov Oskar I. Koifman Yuriy A. Zhabanov 《化学:亚洲杂志》2020,15(1):61-65
Reduction of free‐base [30]trithia‐2,3,5,10,12,13,15,20,22,23,25,30‐dodecaazahexaphyrin (H3Hhp) yields {cryptand[2.2.2](K)}2{(K)(H3Hhp)2}?4C6H4Cl2 ( 1 ) containing double‐decker {(K)(H3Hhp)2} ? 2? radical dianions, whose structure was elucidated using X‐ray diffraction. Potassium ion forms 12 short (K+)???N(H3Hhp) contacts with two H3Hhp macrocycles in the 3.048–3.157 Å range. Dianions have S=1/2 spin state manifesting an effective magnetic moment of 1.64 μB at 300 K and a narrow Lorentzian electron paramagnetic resonance signal. Quantum chemical calculations support the ionic nature of the (K+)‐N(H3Hhp) interactions and the nearly equal distribution of the ?1.5 charge over each macrocycle. H3Hhp takes the role of an aza‐crown ether in free‐base reduced state and forms a new type of double‐decker complex. 相似文献
6.
Dr. Guangwu Li Dr. Tullimilli Y. Gopalakrishna Dr. Hoa Phan Dr. Tun Seng Herng Prof. Jun Ding Prof. Jishan Wu 《Angewandte Chemie (International ed. in English)》2018,57(24):7166-7170
A dithieno[a,h]‐s‐indacene‐ (DTI‐) based diradicaloid DTI‐2Br was synthesized and its open‐shell singlet diradical character was validated by magnetic measurements. On the other hand, its macrocyclic trimer DTI‐MC3 and tetramer DTI‐MC4 turned out to be closed‐shell compounds with global antiaromaticity, which was supported by X‐ray crystallographic analysis and NMR spectroscopy, assisted by ACID and 2D‐ICSS calculations. Such change can be explained by a subtle balance between two types of antiferromagnetic spin–spin coupling along the π‐conjugated macrocycles. The dications of DTI‐MC3 and DTI‐MC4 turned out to be open‐shell singlet diradical dications, with a singlet–triplet energy gap of ?2.90 and ?2.60 kcal mol?1, respectively. At the same time, they are both global aromatic. Our studies show that intramolecular spin–spin interactions play important roles on electronic properties of π‐conjugated macrocycles. 相似文献
7.
AlexeiD. Averin OlesyaA. Ulanovskaya IlyaA. Fedotenko AnatoliiA. Borisenko MarinaV. Serebryakova IrinaP. Beletskaya 《Helvetica chimica acta》2005,88(7):1983-2002
Pd‐Catalyzed amination of 3,5‐dibromo‐ and 3,5‐dichloropyridine ( 1a and 1b , resp.) with linear polyamines 2 leads to the formation of a new family of pyridine‐containing macrocycles 3 with an ‘exo’‐oriented pyridine N‐atom (Schemes 1 and 2). The dependence of the macrocycle yield on the nature of the halogen atom, the length of the polyamine chain and C/N atom ratio, and the composition of the catalytic system is studied. The synthesis of mono‐ and bis(5‐halopyridin‐3‐yl)‐substituted polyamines 4, 5, 8, 9 , and of 3,5‐bis(polyamino)‐substituted pyridines 6 is described (Schemes 3 and 4), and the use of these compounds as intermediates on the way to the macrocycles 7, 16 , and 18 with larger cavity (‘cyclodimers’ and ‘cyclotrimers’) is demonstrated (Schemes 5–10). 相似文献
8.
Pingchun Wei Kai Zhang Dr. Xin Li Deying Meng Prof. Dr. Hans Ågren Prof. Dr. Zhongping Ou Prof. Dr. Seikweng Ng Prof. Dr. Hiroyuki Furuta Prof. Dr. Yongshu Xie 《Angewandte Chemie (International ed. in English)》2014,53(51):14069-14073
The first neo‐confused hexaphyrin(1.1.1.1.1.0) was synthesized by oxidative ring closure of a hexapyrrane bearing two terminal “confused” pyrroles. The new compound displays a folded conformation with a short interpyrrolic C???N distance of 3.102 Å, and thus it readily underwent ring fusion to afford a neo‐fused hexaphyrin with an unprecedented 5,5,5,7‐tetracyclic ring structure. Furthermore, coordination of CuII triggered a ring opening/contracting reaction to afford a CuII complex of an N‐linked pentaphyrin derivative. The roles of reactive N? C bonds in the porphyrinoid macrocycles were demonstrated. 相似文献
9.
Boron Difluoride Complexes of Expanded N‐Confused Calix[n]phyrins That Demonstrate Unique Luminescent and Lasing Properties 下载免费PDF全文
Dr. Masatoshi Ishida Toshihiro Omagari Ryuji Hirosawa Keisuke Jono Dr. Young Mo Sung Dr. Yuhsuke Yasutake Prof. Dr. Hidemitsu Uno Dr. Motoki Toganoh Prof. Dr. Hajime Nakanotani Prof. Dr. Susumu Fukatsu Prof. Dr. Dongho Kim Prof. Dr. Hiroyuki Furuta 《Angewandte Chemie (International ed. in English)》2016,55(39):12045-12049
Complexation of novel multiply N‐confused expanded calix[n]phyrins with boron difluoride afforded a new class of cyclic BODIPY (boron‐dipyrromethene) arrays. The structures of circularly arranged BODIPY subunits linked in an N‐confused fashion give rise to such photophysical properties unique to the macrocycles as redshifted emission wavelengths along with apparent large Stokes shifts, long emission lifetimes, and solid‐state lasing. The DFT calculations support the size‐dependent excited‐state dynamics of the macrocycles. 相似文献
10.
Dr. Shin‐ichiro Kawano Takashi Hamazaki Atsushi Suzuki Kenshin Kurahashi Prof. Dr. Kentaro Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15674-15683
A new series of shape‐persistent imine‐bridged macrocycles were synthesized based on dynamic covalent chemistry. The macrocycles had an alternating sequence of dibenzothiophene and N,N′‐bis(salicylidene)‐ethylenediamine (salen) tethering branched alkyl chains. The macrocycles and tetranuclear metallomacrocycles bearing long and branched alkyl chains exhibited thermotropic columnar liquid‐crystalline phases over a wide temperature range and the metallomacrocycles greatly depended on the characteristics of the coordinated metal ions. The metal‐free macrocycle showed a liquid‐crystalline phase with a lamellar structure and poor birefringence. In sharp contrast, the macrocyclic Ni complex showed a columnar oblique liquid‐crystalline phase, whereas the Pd and Cu complexes showed columnar liquid‐crystalline phases with a lamellar structure. The macroscopic organization and thermal properties of the corresponding liquid‐crystalline metallomacrocycles were significantly dependent on the subtle structural differences among the planar macrocycles, which were revealed by single‐crystal X‐ray crystallographic analysis of the macrocycles with shorter alkyl chains. 相似文献
11.
The two epimers (?)‐ 1a and (?)‐ 1b of the macrocyclic lactam alkaloid 3‐hydroxycelacinnine with the (2R,3R) and (2R,3S) absolute configurations, respectively, were synthesized by an alternative route involving macrocyclization with the regio‐ and stereoselective oxirane‐ring opening by the terminal amino group (Schemes 2 and 6). Properly N‐protected chiral trans‐oxirane precursors provided (2R,3R)‐macrocycles after a one‐pot deprotection‐macrocyclization step under moderate dilution (0.005–0.01M ). The best yields (65–85%) were achieved with trifluoroacetyl protection. Macrocyclization of the corresponding cis‐oxiranes was unsuccessful for steric reasons. Inversion at OH? C(3) via nucleophilic displacement of the cyclic sulfamidate derivative with NaNO2 led to (2R,3S)‐macrocycles. The synthesized (?)‐(2R,3S)‐3‐hydroxycelacinnine ((?)‐ 1b ) was identical to the natural alkaloid. 相似文献
12.
A facile synthetic approach was adopted towards the synthesis of benzo‐fused macrocyclic lactams 2a – 2g via the base‐catalyzed condensation reaction of 2,2′‐[alkanediylbis(oxy)]bis[benzaldehydes] 3a – 3c with N,N′‐substituted bis[2‐cyanoacetamide] derivatives 7a – 7c (Scheme 2). The latter compounds were obtained by the reaction of the appropriate diamines 6a – 6c with ethyl 2‐cyanoacetate ( 4 ). Attempts to prepare the oxaaza macrocycles 2 by alternative pathways were also investigated. The novel pyrazolo‐fused macrocycles 13a and 13b were obtained in 48 and 52% yield, respectively, upon treatment of 2d and 2g with NH2NH2?H2O at 100° (Scheme 4). 相似文献
13.
John N. Low Antonio Quesada Antonio Marchal Manuel Melguizo Manuel Nogueras Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o289-o294
Molecules of 2‐amino‐4,6‐dimethoxypyrimidine, C6H9N3O2, (I), are linked by two N—H?N hydrogen bonds [H?N 2.23 and 2.50 Å, N?N 3.106 (2) and 3.261 (2) Å, and N—H?N 171 and 145°] into a chain of fused rings, where alternate rings are generated by centres of inversion and twofold rotation axes. Adjacent chains are linked by aromatic π–π‐stacking interactions to form a three‐dimensional framework. In 2‐benzylamino‐4,6‐bis(benzyloxy)pyrimidine, C25H23N3O2, (II), the molecules are linked into centrosymmetric R(8) dimers by paired N—H?N hydrogen bonds [H?N 2.13 Å, N?N 2.997 (2) Å and N—H?N 170°]. Molecules of 2‐amino‐4,6‐bis(N‐pyrrolidino)pyrimidine, C12H19N5, (III), are linked by two N—H?N hydrogen bonds [H?N 2.34 and 2.38 Å, N?N 3.186 (2) and 3.254 (2) Å, and N—H?N 163 and 170°] into a chain of fused rings similar to that in (I). 相似文献
14.
Hiroyuki Furuta Prof. Dr. Hideki Nanami Tatsuki Morimoto Dr. Takuji Ogawa Prof. Dr. Vladimir Král Dr. Jonathan L. Sessler Prof. Dr. Vincent Lynch Dr. 《化学:亚洲杂志》2008,3(3):592-599
The new N‐confused porphyrin (NCP) derivatives, meso‐unsubstituted β‐alkyl‐3‐oxo N‐confused porphyrin (3‐oxo‐NCP) and related macrocycles, were synthesized from appropriate pyrrolic precursors by a [3+1]‐type condensation reaction. 3‐Oxo‐NCP forms a self‐assembled dimer in dichloromethane that is stabilized by complementary hydrogen‐bonding interactions arising from the peripheral amide‐like moieties. The protonated form of 3‐oxo‐NCP was observed to bind halide anions (F?, Cl?) through the outer NH and the inner pyrrolic NH groups, thus affording a dimer in dichloromethane. The structure of the chloride‐bridged dimer in the solid state was determined by X‐ray diffraction analysis. 相似文献
15.
Christopher Glidewell John N. Low Susan A. McWilliam Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o100-o102
Molecules of the title compound (systematic name: 2‐amino‐3‐bromo‐5‐nitrobenzonitrile), C7H4BrN3O2, are linked by N—H?N and N—H?O hydrogen bonds [H?N 2.19 Å, N?N 3.019 (4) Å and N—H?N 157°, and H?O 2.17 Å, N?O 2.854 (3) Å and N—H?O 134°] to form (10) sheets built from alternating R(12) and R(36) rings, both of which are centrosymmetric. 相似文献
16.
Delphine Prvot Christophe Galliot Anne-Marie Caminade Jean Pierre Majoral 《Heteroatom Chemistry》1995,6(4):313-318
Phosphorus dialdehydes RP (OC6H4CHO)2 (R = Ph, Me2N) react with phosphodihydrazides PhP(Y)-[N(CH3)NH2]2 (Y = S, O) to give macrocycles 6a–c arising from [2 + 2] cyclocondensation reactions. Treatment of phosphodihydrazone PhP(S) [OC6H4CH N–N(Me)H]2 7 with phenyldichlorophosphine affords macrocycle 8 possessing tri and tetracoordinated phosphorus atoms. Clean desulfurization of thiophosphorus macrocycles 9 and 12 gives rise selectively to new tricoordinated phosphorus containing macrocycles 11 and 13 . 相似文献
17.
A new ligand containing selenium, Se (CH2‐N‐Btrzole)2 (Lse) (Btrzole = benzotriazole) and its cobalt(II) complex, Co(Lse)2(SCN)2, have been synthesized and the molecular structures of the title compounds have been determined by X‐ray techniques. The Lse is a meso‐configuration with a symmetric plane through the Se center, the intermolecular weak interactions of Se? Se, Se? N and π? π stacking between benzotriazole rings to extend the molecular structure to two‐dimensional network configuration. In the Co(II) complex, the metal center is in a six‐coordinated octahedral environment. Two Co(II) atoms are linked by two ligands to form a 20‐membered macrocycle; the adjacent macrocycles are linked by coordinated bond of Co? Nbentrozole to extend an infinite double strained chain. The SOD activity of the ligand and Co(II) complex have been studied by using the pyrogallol autoxidation method; thermal properties and luminescent properties of Co(II) complex have been tested, and the details of those properties have been discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
18.
N‐Doped Carbon Networks: Alternative Materials Tracing New Routes for Activating Molecular Hydrogen 下载免费PDF全文
Dr. Remedios Cortese Dr. Francesco Ferrante Dr. Stefan Roggan Prof. Dario Duca 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3806-3814
The fragmentation of molecular hydrogen on N‐doped carbon networks was investigated by using molecular (polyaromatic macrocycles) as well as truncated and periodic (carbon nanotubes) models. The computational study was focused on the ergonicity analysis of the reaction and on the properties of the transition states involved when constellations of three or four pyridinic nitrogen atom defects are present in the carbon network. Calculations show that whenever N‐defects are embedded in species characterized by large conjugated π‐systems, either in polyaromatic macrocycles or carbon nanotubes, the corresponding H2 bond cleavage is largely exergonic. The fragmentation Gibbs free energy is affected by the final arrangement of the hydrogen atoms on the defect and by the extension of the π‐electron cloud, but it is not influenced by the curvature of the system. 相似文献
19.
Kazuaki Ito Takanori Nagai Yoshihiro Ohba Tyo Sone 《Journal of heterocyclic chemistry》2000,37(5):1121-1128
Decahomotetrathiacalix[6]arenes were conveniently prepared from the 2:2 cyclization reactions of bis(chloromethyl)phenol‐formaldehyde trimers with 1,2‐ethanedithiol in high yields. In contrast, the simi lar reactions of the trimers with 1,3‐propanedithiol instead of 1,2‐ethanedithiol gave 1:1 macrocycles, hexahomodithiacalix[3]arenes, in good yields. Homoazacalixarenes were also prepared from the analogous reactions using piperazines. These macrocycles adopt a cone‐like form as a preferable conformation in solution. 相似文献
20.
Dr. Naila Assem David J. Ferreira Prof. Dr. Dennis W. Wolan Prof. Dr. Philip E. Dawson 《Angewandte Chemie (International ed. in English)》2015,54(30):8665-8668
Macrocyclization is a broadly applied approach for overcoming the intrinsically disordered nature of linear peptides. Herein, it is shown that dichloroacetone (DCA) enhances helical secondary structures when introduced between peptide nucleophiles, such as thiols, to yield an acetone‐linked bridge (ACE). Aside from stabilizing helical structures, the ketone moiety embedded in the linker can be modified with diverse molecular tags by oxime ligation. Insights into the structure of the tether were obtained through co‐crystallization of a constrained S‐peptide in complex with RNAse S. The scope of the acetone‐linked peptides was further explored through the generation of N‐terminus to side chain macrocycles and a new approach for generating fused macrocycles (bicycles). Together, these studies suggest that acetone linking is generally applicable to peptide macrocycles with a specific utility in the synthesis of stabilized helices that incorporate functional tags. 相似文献