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1.
D3h‐Symmetric Porphyrin‐Based Rigid Macrocyclic Ligands for Multicofacial Multinuclear Complexes in a One‐Nanometer‐Sized Cavity 下载免费PDF全文
Yohei Ohkoda Akane Asaishi Tomoya Namiki Tomoaki Hashimoto Midori Yamada Koichiro Shirai Yuta Katagami Dr. Tomoaki Sugaya Prof. Makoto Tadokoro Prof. Akiharu Satake 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11745-11756
The one‐step synthesis of D3h‐symmetric cyclic porphyrin trimers 1 composed of three 2,2′‐[4,4′‐bis(methoxycarbonyl)]bipyridyl moieties and three porphyrinatozinc moieties was achieved from a nickel‐mediated reductive coupling of meso‐5,15‐bis(6‐chloro‐4‐methoxycarbonylpyrid‐2‐yl)porphyrinatozinc. Although cyclic trimers 1 were obtained as a mixture that included other cyclic and acyclic porphyrin oligomers, an extremely specific separation was observed only for cyclic trimers 1 when using columns of silica gel modified with pyrenylethyl, cyanopropyl, and other groups. Structural analysis of cyclic trimers 1 was carried out by means of NMR spectroscopy and X‐ray crystallography. Treatment of an η3‐allylpalladium complex with a cyclic trimer gave a tris(palladium) complex containing three η3‐allylpalladium groups inside the space, which indicated that the bipyridyl moieties inside the ring could work as bidentate metalloligands. 相似文献
2.
Midori Kobayashi Hitoshi Awoki Yoshimi Nakazaki Gisaku Nakamura 《Graphs and Combinatorics》1989,5(1):243-244
In this paper, a perfect one-factorization ofK
36 is given, which is factor-1-rotational. 相似文献
3.
Stability of porphyrin-calix[4]arene complexes analyzed by electrospray ionization mass spectrometry
Arai S Ishihara S Takeoka S Ohkawa H Shibue T Nishide H 《Rapid communications in mass spectrometry : RCM》2004,18(18):2065-2068
The stability of some porphyrin-calix[4]arene sodium-ion complexes were determined by a collision-activated decomposition (CAD) method utilizing electrospray ionization mass spectrometry (ESI-MS). Comparing the values of E(1/2), the collision energy at which the relative intensity of the complex ion is 0.5, we found that the porphyrin-calix[4]arene complex with the higher value of E(1/2) corresponded to that with the larger association constant (Kass), as measured by 1H-NMR in CDCl3. Both our ESI-MS and NMR studies proved that the number of hydrogen bonds and the rigidity of the calix[4]arene stabilized the complex. The ESI-MS technique could be successful in screening the binding affinity in host-guest systems with a small amount of sample. 相似文献
4.
Kiyoharu Nishide Shin-ichi Ohsugi Tetsuo Miyamoto Kamal Kumar Manabu Node 《Monatshefte für Chemie / Chemical Monthly》2004,135(2):189-200
Summary. Development of new odorless thiols (dodecanethiol, 4-n-heptylphenylmethanethiol, 4-trimethylsilylphenylmethanethiol, 4-trimethylsilylbenzenethiol) and an odorless sulfide (1-methylsulfanyldodecane) and their applications to dealkylation, Michael addition, Swern oxidation, and Corey-Kim oxidation are described. 相似文献
5.
Shin-ichi OhsugiKiyoharu Nishide Keiji OonoKazunori Okuyama Masato FudesakaSumiaki Kodama Manabu Node 《Tetrahedron》2003,59(42):8393-8398
Development of the odorless dodecyl methyl sulfide (Dod-S-Me, 1) as an alternative for dimethyl sulfide (DMS) and new odorless methods for the Corey-Kim and Swern oxidations are described. These reactions have been developed with a view toward green chemistry, utilizing Dod-S-Me (1) and common solvents instead of dichloromethane. 相似文献
6.
Komatsu T Hayakawa S Tsuchida E Nishide H 《Chemical communications (Cambridge, England)》2003,(1):50-51
alpha-Cyclodextrin (alpha CD)-penetrating 2-methyl-1-phenethylimidazole coordinates to the zinc(II) and iron(II) complexes of meso-tetrakis[o-(N-methyl)pyridinium] porphyrinate, giving non-covalently linked alpha CD-porphyrin ensembles; the iron(II) complex can reversibly bind and release dioxygen in aqueous DMF solution. 相似文献
7.
[reaction: see text] The Michael addition to alpha-substituted alpha,beta-unsaturated esters and amides using complex A containing a chiral odorless thiol proceeded diastereoselectively. The Michael adducts were converted to beta-mercapto esters and amides via a Wagner-Meerwein rearrangement with boron trifluoride etherate and a thiol exchange reaction using odorless 1-dodecanethiol. This conversion constitutes a formal asymmetric Michael addition of hydrogen sulfide to alpha,beta-unsaturated carbonyl compounds using odorless thiols instead of the toxic hydrogen sulfide. 相似文献
8.
Star-shaped poly(1,2-phenylenevinylene)s 4-substituted with multiple pendant phenoxyls (2 and 3) were synthesized by polymerizing 2-bromo-4-(acetoxyphenyl)styrene in the presence of 1,3,5-triiodobenzene or 1,3,5-tris(3',5'-diiodophenyl)benzene as the core via a simple one-pot Heck reaction and subsequent hydrolysis, phenolate formation, and heterogeneous oxidation. ESR spectra indicated a delocalized spin distribution into the core parts of the star-shaped molecules. The polyradicals, 2 and 3, were in a high-spin state at low temperature, and the ferromagnetic behavior was enhanced for the polyradical with a higher molecular weight. Although an average S of 3 remained at 3/2 to 4/2, the polyradical 2 even with a spin concentration of 0.8 spin/unit revealed an average S of 7/2 to 8/2. The 1,3,5-benzene core acted as an effective magnetic coupler to align the spins of the pendant phenoxyls through the star-shaped pi-conjugated backbone. 相似文献
9.
In the presence of CuCN, reaction of γ,γ-dialkoxyallylic zirconium species 1 with imines proceeded at the γ-position of 1 to give gem-dialkoxyhomoallylic amines 3 in high yield. In this reaction, γ,γ-dialkoxyallylic zirconium species 1 acts as an α,β-unsaturated acyl anion equivalent. 相似文献
10.
Phenyltrimethylsilane possesses a higher HOMO energy (–9.34 eV) than nonsubstituted benzene (>0.41 eV). The π electron of the phenyltrimethylsilane localizes on the benzene ring at the ipso position rather than at the para position. Two center energies calculated by the MNDO-PM3 method indicate that the C? Si bond is facilitated to cleave in comparison with the C? H (para position) one of the benzene ring. Phenyltrimethylsilane and phenyl bis(trimethylsilane) were polymerized with sulfur chloride through the cationic oxidative polymerization. The product is isolated as oligo(p-phenylene sulfide), with a melting point of 150–190°C. An electrophile attacks the carbon atom linked to the Si atom in phenyltrimethylsilane. The new synthetic route of PPS can be established on the basis of the computational calculation. 相似文献