scholarly journals SPECTROSCOPICALLY AND/OR STRUCTURALLY INTRIGUING PHTHALOCYANINES AND RELATED COMPOUNDS. PART 2. MONOMERIC SYSTEMS

Author(s):  
Nagao Kobayashi

The second part of the series of review papers on the properties of some synthetically and spectroscopically interesting studies of our group for the period 2007-2017 is presented. In particular, examples of the analysis of spectroscopic data in combination with calculations by the molecular orbitals method are given. We mainly used spectroscopic methods of electron absorption and natural and magnetic circular dichroism, periodically applying fluorescence, phosphorescence and ESR with a time resolution. The spectra of (4n + 2) p systems, as well as some 4np antiaromatic systems, are analyzed theoretically, which helps the reader to interpret the spectral data. In the first and the second parts of this review monomer systems are considered, and in the third - trimeric and tetrameric systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . .. . . .. .. .. . . . . . . . . . . . . . . .. . . . . . .. . . .. .. . .. . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. . . .. . . . . . . . .. .. . . . . . . .. . . . . . . .. . . .. . . . .. . . .. . . . . . .. . . .. .. . . . . . .. . . . .. . .. .. . .

Author(s):  
Nagao Kobayashi

This work is the third part of the review, which presents the properties of a large group of phthalocyanines, which were synthesized and spectroscopically and theoretically studied in works performed under the guidance of the author for the period 2007-2017. Examples of the analysis of spectroscopic data in combination with quantum-chemical calculations of different level are given. As spectroscopic methods, we used the methods of electron absorption, natural and magnetic circular dichroism (CD and MCD) fluorescence, phosphorescence, and electron paramagnetic resonance with time resolution. Based on quantum-chemical calculations, the spectra of (4n + 2) p systems, as well as some 4np antiaromatic systems, were theoretically analyzed. Unlike the first and second parts of the review, this part deals with dimeric and tetrameric systems. <span style="opacity: 0;"> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . </span> <span style="opacity: 0;"> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . </span>


Author(s):  
Nagao Kobayashi

The first part of the series of review papers on the properties of some synthetically and spectroscopically interesting studies of our group for the period 2007-2017 is presented. In particular, examples are shown on the analysis of spectroscopic data in conjunction with molecular orbital (MO) calculations. We have used mainly electronic absorption and natural and magnetic circular dichroism (CD and MCD) spectroscopic techniques, with occasional use of fluorescence, phosphorescence, and time-resolved EPR. Not only the spectra of (4n + 2)π systems, but also some 4nπ anti-aromatic systems are theoretically analyzed, which helps the reader to learn how to interprete the spectral data. In the first part and the second part of this review monomer systems are considered, and in the third - trimeric and tetrameric systems. <span style="opacity: 0;"> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . </span>


2008 ◽  
Vol 3 (10) ◽  
pp. 1934578X0800301
Author(s):  
Xia-Chang Wang ◽  
Shi-Ping Ma ◽  
Jing-Han Liu ◽  
Li-Hong Hu

Two new guaiane sesquiterpenoids named jatrophaols A and B (1, 2), along with three known analogues, were isolated from the roots of Jatropha curcas. Their structures were determined by spectroscopic methods, including 1D and 2D NMR spectroscopy, HR-EI-MS, HR-ESI-MS, and X-ray diffraction, as well as by comparison of their spectral data with those of related compounds.


2013 ◽  
Vol 68 (1-2) ◽  
pp. 3-7 ◽  
Author(s):  
Renuka Jaina ◽  
Satish C. Jain ◽  
Teena Bhagchandani ◽  
Namita Yadav

Two new furanocoumarins, 5-(1”,1”-dimethylallyl)-8-methyl psoralen (1) and 2-O-acetyl oxypeucedanin hydrate-3”-methyl ether (2), were isolated from the root heartwood of Ficus carica Linn. together with three known furanocoumarins, two triterpenoids, two long-chain compounds, and a steroid. Their structures and relative confi gurations were elucidated by spectroscopic methods (IR, HR-ESI-MS, and NMR) and by comparison of their NMR spectral data with those of related compounds


2011 ◽  
Vol 76 (9) ◽  
pp. 1133-1139 ◽  
Author(s):  
Pham Thi Nhat Trinh ◽  
Nguyen Cong Hao ◽  
Phan Thanh Thao ◽  
Le Tien Dung

From the ethanol extract of Drynaria fortunei (KUNZE) J. Sm., a new phenylpropanoid glycoside, fortunamide (1), was isolated and characterized by spectroscopic methods. Together with a new glycoside, 9 known compounds, including three curcuminoids (2–4), two isoprenylated flavonoids (5, 6), two flavonoids (7, 8), one monoterpenoid (9) and one phenolic acid (10) were isolated and identified by spectral data analysis from the rhizomes of Drynaria fortunei (KUNZE) J. Sm. Eight of them were isolated from Drynaria fortunei (KUNZE) J. Sm. for the first time.


2006 ◽  
Vol 59 (1) ◽  
pp. 59 ◽  
Author(s):  
Craig J. Roxburgh ◽  
Lee Banting

We have found that the hydrochloride of 2-phenyl-2-[2-(2-piperidyl)ethyl]-4,5,6,7-tetrahydroindan-1,3-dione 1 possesses marked analgesic activity (100% inhibition referenced to codeine) and report, as part of an extensive synthetic program, the synthesis of 38 new and structurally related compounds. Selective catalytic hydrogenation of the pyridine ring of 2-phenyl-2-[2-(2-pyridyl)ethyl]-indan-1,3-dione 2 yields the nine-membered nitrogen-containing heterocycle 6 by a novel ring cyclization–expansion reaction. The structural and functional group parameters required for this novel ring-expansion reaction have been extensively and thoroughly investigated through the synthesis of a series of structurally related compounds; principally by modification, substitution, and replacement of the various functionality contained within 2. In addition, we report the synthesis of a series of new 2-methyl-2-(ω-N-phthalimidoalkyl)-indan-1,3-diones 41, 45, and 53, two of which, like the parent 2-phenyl substituted indan-1,3-dione 2, also undergo a novel ring cyclization–expansion reaction to yield eight- and nine-membered nitrogen-containing rings. However, in these cases, further transannular reactions occur to produce the new 5,5- and 5,6-ring-fused nitrogen-containing heterocycles 44, 48 and 51, 52. Hydrazinolysis of the third, 2-methyl-2-(4-N-phthalimidobutyl)-indan-1,3-dione yields the new azepine-containing ring structure 56 by direct cyclization. Furthermore, some interesting and unexpected chemical properties of the final compounds, which include selective and non-selective pyridine-ring hydrogenations and a few unexpected side reactions, are described.


2020 ◽  
Vol 62 (11) ◽  
pp. 1860
Author(s):  
В.И. Веттегрень ◽  
А.Г. Кадомцев ◽  
И.П. Щербаков ◽  
Р.И. Мамалимов ◽  
В.Б. Кулик

Raman spectrum of the surface layer with a thickness of approximately 80 nm of a porous carbon ceramic was obtained (the porosity was used equal to 5%). Spectrum analysis showed that the ceramics contains crystals of silicon carbide - 6H-SiC and silicon. The destruction of ceramics by diamond microcrystals resulted in fractoluminescence (FL). Spectrum of FL contains two bands at 1.6 and 1.9 eV. The first band is formed by breaking down the silicon crystals, and the second band is formed by breaking down the 6H-SiC crystals. The time dependence of the intensity of FL signals with a time resolution of 2 ns is obtained. Three types of signals were observed: one type of signal is formed when the 6H-SiC crystals break down, the second type of signal is formed when the silicon crystals break down, and the third type of signal is formed when these crystals break down simultaneously. The appearance of signals is associated with the formation of cracks arising from the breaking down of the barriers formed at the intersection of slip planes of dislocations in silicon carbide and silicon crystals. The size of cracks in 6H-SiC is estimated: the smallest ones is 5.5 nm, and the largest is approximately 18 nm.


2009 ◽  
Vol 13 (02) ◽  
pp. 275-282 ◽  
Author(s):  
Ning Sheng ◽  
Jing Sun ◽  
Yongzhong Bian ◽  
Jianzhuang Jiang ◽  
Dong Xu

Novel heteropentameric porphyrins-pyrene arrays, in which four meso-tetraphenyl porphyrins are linked to the center unit of pyrene by four acetylenyl bonds, were designed and synthesized. The newly synthesized heteropentameric compounds have been characterized by a wide range of spectroscopic methods. The third-order nonlinear optical (NLO) properties of both the metal-free and zinc compounds of the three-dimensional arrays were investigated by Z-scan experiments, showing enhanced NLO properties compared with that of the porphyrin and pyrene monomers.


Author(s):  
NAGAO KOBAYASHI

The synthesis of and spectroscopic data on subazaporphyrins, subphthalocyanines, subnaphthalocyanines and their related compounds reported to date are summarized, together with the results of molecular orbital (MO) calculations from our laboratory. Thus the problems and key points in the synthesis of these subazamacrocycles and their electronic absorption and magnetic circular dichroism (MCD) spectra are discussed, together with those of the monosubstituted-type low-symmetrical phthalocyanines obtained by their ring expansion reaction. The Q bands of these subazamacrocycles are orbitally doubly degenerate, and in the Soret band region, three transitions to the orbitally degenerate state are found. The MO calculations suggest that the HOMO levels destabilize considerably while the LUMO levels change slightly with increasing size of the π system. In addition, the electronic adsorption data are reproduced by the calculation only when the two pyrrole hydrogens in the monosubstituted-type phthalocyanines are assumed to be linked to the two pyrrole nitrogens along the short axis.


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