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133 results on '"Miyamoto, Hisakazu"'

4. Enantioselective photocyclization of amides to beta-lactam derivatives in inclusion crystals with an optically active host

Author

Toda, Fumio, Miyamoto, Hisakazu, Inoue, Mitsuhiro, Yasaka, Shunpei, and Matijasic, Ivanka

Subjects
Organic compounds -- Synthesis, Beta lactam antibiotics -- Research, Amides -- Analysis, Crystals -- Structure, Biological sciences, Chemistry
Abstract

Research describes a higly enantioselective photocyclization conversion of amides to beta-lactams employing host-guest interaction in chiral crystals. X-ray diffraction analyses of the crystals are presented.

Published
2000

5. Enantioselective photochemical reactions of N-phenyl enaminones in inclusion complex crystals using a chiral host compound

Author

Toda, Fumio, Miyamoto, Hisakazu, Tamashima, Tomoyuki, Kondo, Masato, and Ohashi, Yuji

Subjects
Crystals -- Structure, Photochemical research -- Analysis, Chirality -- Research, Biological sciences, Chemistry
Abstract

Research was conducted to determine the enantioselective reaction of N-methyl-N-phenyl-3-amino-2-cyclohexen-1-one derivatives to the corresponding N-methylhexahydro-4-carbazolones. The photocyclization reaction was tested in a water suspension of 1:1 inclusion compounds of the starting material consisting of optically active host compounds obtained from tartaric acid. Results indicate that the cyclohexenone and phenyl groups of the reactant exist in distant and close positions, respectively, in the two inclusion compounds.

Published
1999

6. Enantioselective photocyclization of N-alkylfuran-2-carboxyanilides to trans-dihydrofuran derivatives in inclusion crystals with optically active host compounds derived from tartaric acid

Author

Toda, Fumio, Miyamoto, Hisakazu, Kanemoto, Kazuyuki, Tanaka, Kiyoaki, Takahashi, Yukiko, and Takenaka, Yasuyuki

Subjects
Organic compounds -- Research, Photosynthesis research -- Analysis, Crystals -- Research, Tartaric acid -- Research, Biological sciences, Chemistry
Abstract

Enantioselective photocyclization of N-alkylfuran-2-carboxyanilides to trans-dihydrofuran derivatives was examined in inclusion crystals with optically active hose compounds derived from tartaric acid. X-ray structural analysis of inclusion crysals was used to study the mechanism of the enantioselective reaction of achiral compounds in inclusion crystals. The results suggested that in some cases, the steric course of the photoreaction vary depending on the types of preparation of inclusion crystals.

Published
1999

7. Crystal structure of N-isopropyl-N-(phenyl)phenylglyoxylamide

Author

Miyamoto, Hisakazu, Yamauchi, Genta, Ueno, Takuya, and UEKUSA, hidehiro

Subjects
crystal structure, isopropyl phenylphenylglyoxylamide photoreaction crystal structure photoreactive property, Hydrogen bond, General Chemistry, Crystal structure, 010402 general chemistry, 010403 inorganic & nuclear chemistry, Condensed Matter Physics, Ring (chemistry), 01 natural sciences, Research Communications, 0104 chemical sciences, Crystal, lcsh:Chemistry, chemistry.chemical_compound, Crystallography, chemistry, lcsh:QD1-999, Amide, Atom, photoreaction, General Materials Science, Acetamide, Isopropyl
Abstract

The title compound, C17H17NO2, was synthesized and its photoreactive properties in the crystalline state were investigated. A solid-state photoreaction did not occur because the reaction sites were too far apart in the mol­ecule., The title compound [systematic name: 2-oxo-N,2-diphenyl-N-(propan-2-yl)acetamide], C17H17NO2, was synthesized and its photoreactive properties in the crystalline state were investigated. In the mol­ecule, the carbonyl group attached to the phenyl ring adopts an s-trans configuration with respect to the isopropyl group. Moreover, the distance between the C atom of the carbonyl group and the N-bound C atom of the isopropyl group is 3.845 (2) Å, which is much longer than 3.2 Å, the threshold for photoreactions to take place in the mol­ecule. As a result, the crystal did not photoreact upon UV light irradiation. In the crystal, the mol­ecules are linked via weak inter­molecular C—H⋯O hydrogen bonds, forming a layer structure parallel to the ab plane.

Published
2018

8. Chiral arrangement of N-ethyl-N-isopropylphenylglycoxylamide molecule in its own crystal and in an inclusion crystal with a host compound and their photoreactions in the solid state that give optically active beta-lactam derivatives. X-ray analytical and CD-spectral studies

Author

Toda, Fumio, Miyamoto, Hisakazu, Koshima, Hideko, and Urbanczyk-Lipkowska, Zofia

Subjects
Chirality -- Research, Amides -- Research, Photochemical research -- Analysis, Beta lactamases -- Research, Biological sciences, Chemistry
Abstract

A study was conducted to characterize the formation of a chiral crystal in the title oxoamide and the photochemical alteration of the chiral crystal to optically active beta-lactam. Continuous measurement of CD spectra were carried out to determine dynamic molecular behaviors in the solid state. Results indicated that glyoxylamide supports the formation of a chiral crystal with achiral molecules arranged in a chiral form.

Published
1997

9. Synthesis, structure, and discrimination of chiral bimolecular crystals by suing diphenylacetic acid and aza aromatic compounds

Author

Koshima, Hideko, Nakagawa, Tsuyoshi, Matsuura, Teruo, Miyamoto, Hisakazu, and Toda, Fumio

Subjects
Crystals -- Growth, Circular dichroism -- Usage, Biological sciences, Chemistry
Abstract

The absolute aysmmetric synthesis of a chiral crystal formed from an achiral molecule is a topic of organic solid state chemistry. A series of two-component crystals where diphenylacetic acid is mixed with aza aromatic compounds, leading to the further formation of another chiral bimolecular crystal with phenanthridine is reported. Solid-state circular dichroism spectrometry is used for chiral discrimination.

Published
1997

10. Optical activity of oxo amide crystals

Author

Asahi, Toru, Nakamura, Makoto, Kobayashi, Jinzo, Toda, Fumio, and Miyamoto, Hisakazu

Subjects
Amides -- Analysis, Oxo compounds -- Analysis, Photochemistry -- Analysis, Beta lactam antibiotics -- Research, Ring formation (Chemistry) -- Research, Chemistry
Abstract

A high accuracy universal polarimeter (HAUP)-based method was utilized to characterize the optical activity of oxo amide crystals which can be transformed photochemically to optically active beta-lactams. HAUP analysis of the oxo amide crystals indicated the presence of constant optical activity in both the reactant and the resulting product during the process of photocyclization. The components of the gyration tensor and birefringence were also negative and were not altered during the formation of (-) and (+)-beta-lactams.

Published
1997

13. Enantioselective Photocyclization of Amides to -Lactam Derivatives in Inclusion Crystals with an Optically Active Host

Author

Toda, Fumio, Miyamoto, Hisakazu, Inoue, Mitsuhiro, Yasaka, Shunpei, and Matijašić, Ivanka

Abstract

Irradiation of inclusion crystals of 2-(N-acyl-N-alkylamino)cyclohex-2-enones and N,N-dimethylphenylglyoxylamide with chiral host molecules gave the opticaly active N-alkyl-1-azaspiro[3,5]-nonane-2,5-diones and 3-hydroxy-1-methyl-3-phenylazetidin-2-one, respectively. The crystal structure of the 1:1 inclusion complex of N,N-dimethylphenylglyoxylamide with (-)-trans-1,4-bis[3-(o-chlorophenyl)-3-hydroxy-3-phenylprop-1-ynyl]-2,3,5,6-tetrachloro-2,5-cyclohexadiene-1,4-diol was analyzed by X-ray diffraction.

Published
2000

14. Preparation of optically active cis-4-methylcyclohex-4-ene-1,2-dicarboximides by a combination of Diels–Alder reaction and complexation with optically active hosts and enantioselective Diels–Alder reaction in inclusion crystals in a water suspension medium

Author

Miyamoto, Hisakazu, Kimura, Taku, Daikawa, Naoki, Tanaka, Koichi, Miyamoto, Hisakazu, Kimura, Taku, Daikawa, Naoki, and Tanaka, Koichi

Abstract

Optically active Diels–Alder adducts were prepared using a one-pot preparative method and enantioselective Diels–Alder reaction with optically active hosts in a water suspension medium.

Published
2011

15. Formation of racemic compound crystals by mixing of two enantiomeric crystals in the solid state. Liquid transport of molecules from crystal to crystal

Author

Toda, Fumio, Tanaka, Koichi, Miyamoto, Hisakazu, Koshima, Hideko, Miyahara, Ikuko, Hirotsu, Ken, Toda, Fumio, Tanaka, Koichi, Miyamoto, Hisakazu, Koshima, Hideko, Miyahara, Ikuko, and Hirotsu, Ken

Abstract

Mixing of powdered (-)- and (+)-enantiomer crystals in the solid state gives crystals of the racemic compound. This racemic crystal formation was followed by IR spectral measurement of a 1 :1 mixture of (-)- and (+)-enantiomer crystals as a Nujol mull. As the formation of racemic crystals proceeds, the OH absorptions of the enantiomer disappear gradually and new OH absorptions due to the racemic compound appear. The formation of racemic crystals from enantiomer crystals has been studied for various kinds of chiral compounds: 2,29-dihydroxy-1,19-binaphthyl (1) and its derivatives, 10,109-dihydroxy-9,99- biphenanthryl (4), 2,29-dihydroxy-4,49,6,69-tetramethylbiphenyl (5) and its derivatives, 4,49-dihydroxy-2,29,3,39,6,69- hexamethylbiphenyl (8), 1,6-di(o-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol (11) and its derivatives, trans-4,5-bis[hydroxy(diphenyl)methyl]-2,2-dimethyl-1,3-dioxacyclopentane (17) and its derivatives, tartaric acid (20) dimethyl tartrate (21), malic acid (22), mandelic acid (23), and norephedrine (24). These molecular movements and blending occur rapidly in the presence of liquids such as liquid paraffin (Nujol), seed oils such as olive, coconut, rapeseed and soybean oil, artificial oil such as silicone oil and water, although the same movement also occurs in the absence of the liquid. For example, keeping a mixture of powdered (-)-1 (1a) and (+)-1 (1b) at room temperature for 48 h gives racemic crystals (1c). However, molecular aggregation sometimes occurs in solution but not in the solid state. For example, recrystallization of (-)-16 (16a) and (+)-16 (16b) from solvent gives racemic crystals of 16c, although mixing of these two components as powders in the presence of liquid does not give 16c. In order to determine the mechanism of the molecular movement in the solid state, X-ray crystal structures of optically active and racemic compounds and also the molecular movements from optically active crystal to racemic crystal have been studied.

Published
2011

16. Enantioselective photocyclization of 2-arylthio-3-methylcyclohexen-1-ones to dihydrobenzothiophene derivatives in an inclusion crystal with an optically active host

Author

Toda, Fumio, Miyamoto, Hisakazu, Kikuchi, Shiro, Kuroda, Reiko, and Nagami, Fuji

Subjects
Ring formation (Chemistry) -- Case studies, Solid state chemistry -- Research, Chemistry
Abstract

The photocyclization of 2-phenylthio-3,5,5-trimethylcyclohexen-1-one to its dihydrobenzothiophene analogue and of 2-arylthio-3-methylcyclohexen-1-ones to the dihydrobenzothiophenes was carried out in inclusion compounds with optically active host molecules. The experiments yielded crystalline products with a substituent at the ortho site of the benzene ring. The high enantioselectivities achieved were attributed to the intermolecular interactions between host and guest molecules which controlled the conformation of the guest molecule.

Published
1996

17. 1:1 and 2:1 inclusion complexes of (R,R)-(-)-trans-2,3-bis(hydroxydiphenyl-methyl)-1,4-dioxaspiro(4.4)nonane with N-allylfuran-2-carboxanilide which upon irradiation in the solid state give (-)- and (+)-photocyclization products, respectively

Author

Toda, Fumio, Miyamoto, Hisakazu, and Kanemoto, Kazuyuki

Subjects
Photochemistry -- Analysis, Chirality -- Research, Crystallization -- Research, Biological sciences, Chemistry
Abstract

Photolysis of furan-2-carboxanilide and N-methylfuran-2-carboxanilide in an inclusion complex with the title chiral host compound successfully produced optically active rac-trans-dihydrofuran derivatives as the sole isolable product. It is the first report of a product chirality control using only one enantiomer of a host compound. Using the title (R,R)-(-)-chiral host compound, either optically pure (-)-rac-trans-dihydrofuran or (+)-rac-trans-dihydrofuran can also be easily obtained.

Published
1996

20. Preparation of optically active cis-4-methylcyclohex-4-ene-1,2-dicarboximides by a combination of Diels–Alder reaction and complexation with optically active hosts and enantioselective Diels–Alder reaction in inclusion crystals in a water suspension medium

Author

Miyamoto, Hisakazu, Kimura, Taku, Daikawa, Naoki, Tanaka, Koichi, Miyamoto, Hisakazu, Kimura, Taku, Daikawa, Naoki, and Tanaka, Koichi

Abstract

Optically active Diels–Alder adducts were prepared using a one-pot preparative method and enantioselective Diels–Alder reaction with optically active hosts in a water suspension medium.

Published
2003

29. Formation of racemic compound crystals by mixing of two enantiomeric crystals in the solid state. Liquid transport of molecules from crystal to crystal

Author

Toda, Fumio, Tanaka, Koichi, Miyamoto, Hisakazu, Koshima, Hideko, Miyahara, Ikuko, Hirotsu, Ken, Toda, Fumio, Tanaka, Koichi, Miyamoto, Hisakazu, Koshima, Hideko, Miyahara, Ikuko, and Hirotsu, Ken

Abstract

Mixing of powdered (-)- and (+)-enantiomer crystals in the solid state gives crystals of the racemic compound. This racemic crystal formation was followed by IR spectral measurement of a 1 :1 mixture of (-)- and (+)-enantiomer crystals as a Nujol mull. As the formation of racemic crystals proceeds, the OH absorptions of the enantiomer disappear gradually and new OH absorptions due to the racemic compound appear. The formation of racemic crystals from enantiomer crystals has been studied for various kinds of chiral compounds: 2,29-dihydroxy-1,19-binaphthyl (1) and its derivatives, 10,109-dihydroxy-9,99- biphenanthryl (4), 2,29-dihydroxy-4,49,6,69-tetramethylbiphenyl (5) and its derivatives, 4,49-dihydroxy-2,29,3,39,6,69- hexamethylbiphenyl (8), 1,6-di(o-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol (11) and its derivatives, trans-4,5-bis[hydroxy(diphenyl)methyl]-2,2-dimethyl-1,3-dioxacyclopentane (17) and its derivatives, tartaric acid (20) dimethyl tartrate (21), malic acid (22), mandelic acid (23), and norephedrine (24). These molecular movements and blending occur rapidly in the presence of liquids such as liquid paraffin (Nujol), seed oils such as olive, coconut, rapeseed and soybean oil, artificial oil such as silicone oil and water, although the same movement also occurs in the absence of the liquid. For example, keeping a mixture of powdered (-)-1 (1a) and (+)-1 (1b) at room temperature for 48 h gives racemic crystals (1c). However, molecular aggregation sometimes occurs in solution but not in the solid state. For example, recrystallization of (-)-16 (16a) and (+)-16 (16b) from solvent gives racemic crystals of 16c, although mixing of these two components as powders in the presence of liquid does not give 16c. In order to determine the mechanism of the molecular movement in the solid state, X-ray crystal structures of optically active and racemic compounds and also the molecular movements from optically active crystal to racemic crystal have been studied.

Published
1997

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