Special Issue

Yuichi Kanaoka's Special Issues, Vol. 59, No. 2, 2003

43 data found. 1 - 30 listed Next Last
Communication | Special issue | Vol 59, No. 2, 2003, pp. 441 - 444
Published online:
DOI: 10.3987/COM-02-S45
Synthesis of (±)-Pinnaic Acid

Ichiro Hayakawa, Hirokazu Arimoto,* and Daisuke Uemura

*Graduate School of Science, Nagoya University, Chikusa, Nagoya, Aichi 464-8602, Japan


(±)-Pinnaic acid (1) was synthesized via the catalytic hydrogenation of an α, β-unsaturated ketone (12) as the key step to construct an aza-spiro skeleton.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 445 - 451
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DOI: 10.3987/COM-02-S47
Trimethylaluminum-promoted 1,4-Addition Reaction of Cuprates to Six or Eight-membered 2-Hydroxymethyl Enones

Khanitha Pudhom, Jun-ichi Matsuo, and Teruaki Mukaiyama*

*The Kitasato Institute, Center for Basic Research, 6-15-5 (TCI), Toshima, Kita-ku, Tokyo 114-0003, Japan


1,4-Addition reaction of higher order cyanocuprates such as Ph2Cu(CN)Li2 and [Et3SiO(CH2)3C(=CH2)]2Cu(CN)Li2 (3) to six or eight-membered cyclic 2-hydroxymethyl enones proceeded efficiently by successive treatment with trimethylaluminum and cuprate reagents. A side chain for C-ring of 19-hydroxypaclitaxel (1) was introduced in high yields on treating highly functionalized eight-membered cyclic hydroxymethyl enone (2c) with trimethylaluminum and cuprate (3).

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 453 - 457
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DOI: 10.3987/COM-02-S53
A Facile and Direct Synthesis of Isoquinolone Derivatives from Allenes: Intramolecular Carbopalladation of Allenes Followed by Amidations

Kazuhiro Watanabe and Kunio Hiroi*

*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan


A new efficient synthesis of isoquinolone skeletons by nucleophilic substitution through intramolecular carbopalladation with the assistance of a catalytic amount of Pd(OAc)2 was developed. Palladium-catalyzed cyclization of (o-iodobenzamidoalkyl)allene compounds afforded the corresponding isoquinolone derivatives in good yields.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 459 - 464
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DOI: 10.3987/COM-02-S54
Acid-catalyzed Photocycloaddition of 6-Chloro-1,3-Dimethyluracil to Polycyclic Aromatic Hydrocarbons

Kazue Ohkura, Shun Uchiyama, Masayuki Sato, James M. Diakur, and Koh-ichi Seki*

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


The acid-catalyzed photoreaction of 6-chloro-1,3-dimethyluracil (6-ClDMU) with various polycyclic arenes was investigated: UV-Irradiation of a solution of 6-ClDMU with phenanthrene (1a), 9-cyanophenanthrene (1b) and pyrene (1f) in cyclohexane effected 1,2-cycloaddition to furnish the corresponding cyclobutapyrimidines as the predominant adducts, while the substitution reaction with acenaphthene (1e) and chrysene (1g) proceeded to give the corresponding 6-aryl-1,3-dimethyluracils.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 465 - 472
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DOI: 10.3987/COM-02-S56
A Synthetic Approach to Bengazoles: A Synthesis of Deacylbengazole

Pabba Chittari, Yasumasa Hamada, and Takayuki Shioiri*

*Graduate School of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan


The synthesis of deacylbengazole (3) and the C1-C9 fragments (4 and 5) of bengazoles was accomplished by use of the Thomas SnCl4-assisted coupling of the oxazole aldehydes with δ-alkoxyallylstannanes followed by the Sharpless asymmetric dihydroxylation as key steps.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 473 - 476
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DOI: 10.3987/COM-02-S64
Synthesis of (3-Indolyl)heteroaromatics by Suzuki-Miyaura Coupling and Their Inhibitory Activity in Lipid Peroxidation

Atsushi Nishida,* Naoki Miyashita, Mihoko Fuwa, and Masako Nakagawa

*Graduate School of Pharmaceutical Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


A variety of (3-indolyl)heteroaromatic compounds were synthesized by Suzuki-Miyaura coupling of 3-indolylboronic acid and halogenated heteroaromatics. 2-(3-Indolyl)thiophene showed potent inhibitory activity against lipid peroxidation by rat liver microsome.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 477 - 480
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DOI: 10.3987/COM-02-S66
First Synthesis of 4,6-Dialkyl-1,2,3- triazines via Dialkylcyclopropenones

Kiyoshi Matsumoto,* Tomasz Girek, Akihiro Okada, and Naoto Hayashi

*Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan


2-Methyl-4,6-dialkyl-1,2,3-triazin-5(2H)-ones (12a-e) were prepared for the first time from the corresponding cyclopropenones that were prepared by Nakamura’s method.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 481 - 484
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DOI: 10.3987/COM-02-S68
A New Efficient Synthesis of Both Enantiomers of Macrosphelide Core: A Potential Precursor for Functionalized Macrosphelides

Yuji Matsuya, Takanori Kawaguchi, Hideo Nemoto,* Hiroshi Nozaki, and Hiroki Hamada

*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, Toyama 930-0194, Japan


The asymmetric synthesis of a macrosphelide core (1) and its enantiomer was achieved from (S)- or (R)-3-hydroxybutyrate in excellent yields. These compounds are potentially useful precursors for the preparation of biologically important macrosphelide analogues.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 485 - 490
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DOI: 10.3987/COM-02-S70
A Stereocontrolled Synthesis of (+)-Rhopaloic Acid A Using a Dioxabicyclo[3.2.1]octane Chiral Building Block

Kohei Kadota and Kunio Ogasawara*

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan


Utilizing a chiral building block having a dioxabicyclo[3.2.1]octane framework, (+)-rhopaloic acid A, a potent cytotoxic norsesterterpene isolated from the marine sponge Rhopaloeides sp., has been synthesized in a stereocontrolled manner.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 491 - 495
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DOI: 10.3987/COM-02-S72
A New Route to the Calcitriol A-Ring Precursor Using a Bicyclo[3.2.1]octane Chiral Building Block

Norio Miyazawa, Ayako Tosaka, Keisuke Hanada, and Kunio Ogasawara*

*Pharnaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan


A concise route to the A-ring precursor of calcitriol (1α,25-dihydroxyvitamin D3) has been developed starting from the chiral building block having a bicyclo[3.2.1]octane framework. Since we have already developed a diastereocontrolled synthesis of the C/D-ring precursor starting with the enantiomeric chiral building block, the present synthesis implies the total synthesis of calcitriol from a single precursor in a formal sense.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 497 - 500
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DOI: 10.3987/COM-02-S74
Structure Determination of Lustromycin, an Antibiotic against Anaerobic Bacteria

Masaki Handa, Hideaki Ui, Daisuke Yamamoto, Soichi Monma, Yuzuru Iwai, Toshiaki Sunazuka, and Satoshi Omura*

*Kitasato Institute for Life Sciences, Kitasato University, and The Kitasato Institute, Shirokane, Tokyo 108-8642, Japan


Extensive homo and heteronuclear two-dimensional NMR studies revealed lustromycin, an anti-anaerobic antibiotic. Its structure consists of a decaline ring system fused to a 10-membered macrolactone and a 14-membered macrolactone having an enol ether moiety conjugated with a maleic anhydride functionality.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 501 - 504
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DOI: 10.3987/COM-02-S75
Hetero Diels-Alder Reaction Catalyzed by New Axially Dissymmetric Ligands with Fluorinated Chiral Centers

Masaaki Omote, Tomokuni Hasegawa, Kazuyuki Sato, Akira Ando, and Itsumaro Kumadaki*

*Faculty of Pharmaceutical Sciences, Setsunan University, 45-1, Nagaotoge-cho, Hirakata-shi, Osaka 573-0101, Japan


We have reported a new type of axially dissymmetric ligand, (R)-bis{(R)-2,2,2-trifluorohydroxyethyl}biphenyl ((R)-(R)2-1), which showed an excellent asymmetric induction in the reaction of Et2Zn to benzaldehyde. Now, a pentafluoroethyl analog of this ligand ((R)-(R)2-6) was synthesized. Both ligands were found to work as a ligand for an asymmetric hetero Diels-Alder reaction of benzaldehyde (2) with the Danishefsky's diene (4). Titanium or aluminum complexes of (R)-(R)2-1 or (R)-(R)2-6 catalyzed this asymmetric reaction moderately to give products of up to 54% ee.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 505 - 508
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DOI: 10.3987/COM-02-S76
Cycloaddition of Naphthalenyl and Anthracenyl Imines: Interesting Aspects of the Staudinger Reaction

Indrani Banik, Linda Hackfeld, and Bimal K. Banik*

*Department of Molecular Pathology, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030, U.S.A.


Cycloaddition of imines derived from naphthalene and anthracene derivatives under Staudinger reaction conditions proceeded exceedingly well with remarkable control of stereochemistry to the corresponding β-lactams.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 509 - 515
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DOI: 10.3987/COM-02-S80
Direct and Stereoselective Construction of β-Mannosidic Linkages Capitalizing on 4,6-O-Benzylidene-protected D-Mannopyranosyl Diethyl Phosphite

Toshifumi Tsuda, Shinya Sato, Seiichi Nakamura, and Shunichi Hashimoto*

*Graduate School of Pharmaceutical Science, Hokkaido University, Sapporo 060-0812, Hokkaido


A direct and practical method for the stereoselective construction of β-mannosidic linkages has been developed by using 2,3-di-O-benzyl-4,6-O-benzylidene-D-mannopyranosyl diethyl phosphite as a glycosyl donor and trimethylsilyl triflate as a promoter.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 517 - 520
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DOI: 10.3987/COM-02-S81
Capture of Phenolic Endocrine Disruptors with 2-Pyridone

Ichiro Takahashi,* Masahiro Takahashi, Hidehiko Kitajima, Masami Wagi, Yumi Takahashi, Machiko Sabi, Minoru Hatanaka, Akihito Yamano, Tomihisa Ohta, and Shinzo Hosoi*

*Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Fukui University, Bunkyo, Fukui 910, Japan


Crystalline molecular complexes between phenolic endocrine disruptors and 2-pyridones were prepared in fairly good isolated yields through simple procedures. Crystal structure of a complex between bisphenol A and 2-pyridone (1:1 molar ratio) is also described.

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Communication | Special issue | Vol 59, No. 2, 2003, pp. 521 - 526
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DOI: 10.3987/COM-02-S87
Synthesis and CD Measurement of Chiral 1-Ethyl-3-carboxy-1,2,3,4-tetrahydro-β-carbolines: C1 Configuration and Second Sphere Chirality

Masashi Yokoya, Kyohei Masubuchi, Mariko Kitajima, Hiromitsu Takayama, and Norio Aimi*

*Graduate School of Pharmaceutical Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


Chiral diastereomers, (1S)-ethyl-(3S)-carboxy-1,2,3,4-tetrahydro- β-carboline and (1R)-ethyl-(3S)-carboxy-1,2,3,4-tetrahydro-β-carboline, were synthesized. Complete 1H and 13C NMR spectral assignments were made and the C-ring conformations were clarified by NMR spectral measurements and DFT potential energy calculation using the 6-31G(d) basis set. CD spectra were measured and the 1Lb band Cotton effects were found to be controlled by both the C1 absolute configuration and the C-ring conformation.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 527 - 540
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DOI: 10.3987/COM-02-S50
Total Synthesis of Lennoxamine and Chilenine via Ring-Expansion of Isoindoloisoquinoline to Isoindolobenzazepine

Yuji Koseki, Shinya Katsura, Shuichi Kusano, Harumi Sakata, Hiroto Sato, Yoshinori Monzene, and Tatsuo Nagasaka*

*Tokyo University of Pharmacy and Life Science, School of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan


Convenient synthesis of the benzazepine alkaloids, lennoxamine (1) and chilenine (2), is described. The key steps are conversion of methylenelactam (5) to an N-tertiary acyliminium ion precursor (16) and a novel expansion of the six-membered ring of 4 to a benzazepine ring system (3b), which could be transformed into lennoxamine (1) and chilenine (2).

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 541 - 546
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DOI: 10.3987/COM-02-S51
Concise Synthesis of Tetrahydrophenanthridone by Palladium Reagent

Takashi Harayama,* Hiroko Toko, Hiromi Nishioka, Hitoshi Abe, and Yasuo Takeuchi

*Faculty of Pharmaceutical Science, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan


Heck reaction of N-(2-halophenyl)-N-methyl-1-cyclohexene-1-carboxamide (1) and 2-bromo-N-methyl-N-phenyl-1-cyclohexene-1-carboxamide (4) using a palladium reagent under several reaction conditions was examined. Reaction of 4 using Pd(OAc)2, DPPP, and Bu3P afforded tetrahydrophenanthridone (5) in excellent yield.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 547 - 571
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DOI: 10.3987/COM-02-S52
Synthesis of Ketosyl Spiro-isoxazolidine by 1,3-Dipolar Cycloaddition of 1-Methylenesugars with Nitrones —A New Access to C-Glycosyl Amino Acids

Xiaoliu Li, Hideyo Takahashi, Hiro Ohtake, and Shiro Ikegami*

*School of Pharmaceutical Sciences, Teikyo University, 1091-1, Sagamiko, Kanagawa 199-0195, Japan


The 1,3-dipolar cycloaddition reactions of 1-methylenesugars (1a~c) with nitrones (2 and 5) were carried out diastereoselectively under the catalysis of BF3·Et2O at low temperature and afforded the α-stereoselective spiro ketosyl isoxazolidines in good to excellent yields. The reductive isoxazolidine ring-opening of the spiro moiety with the treatment of zinc and acetic acid resulted in a new kind of C-glycosyl amino acid possessing a ketose form, providing an access to C-glycosyl amino acids. The structures of the synthesized compounds were confirmed by the spectroscopic analyses.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 573 - 585
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DOI: 10.3987/COM-02-S55
Investigation of the Ring-opening Cross-Metathesis Reaction of 2-Azabicyclo[2.2.1]hept-5-en-3-one (ABH) with Allylsilanes

Minoru Ishikura,* Makoto Saijo, and Ayako Hino

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


An examination of the ring-opening cross-metathesis reaction of N-substituted 2-azabicyclo[2.2.1]hept-5-en-3-ones (ABH) (1) with allylsilanes (2) in the presence of ruthenium catalysts was undertaken.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 587 - 593
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DOI: 10.3987/COM-02-S57
Synthesis and Character of New Bis(isoxazoline) Ligands

Toshio Shinohara, Kazuhiko Wakita, Midori A. Arai, Takayoshi Arai, and Hiroaki Sasai*

*The Institute of Scientific and Industrial Research, Osaka University, 8-1. Mihogaoka, Ibaraki, Osaka 567-0047, Japan


Synthesis of two kinds of new bis(isoxazoline) ligand, achiral 2,2’-bis(isoxazolinyl)propane and (R)-2,2’-bis(isoxazolinyl)-1,1’-binaphthyl bearing an axial chirality is described. Both of the bis(isoxazoline) ligands accelerated the Pd(II)-catalyzed Wacker-type cyclization of alkenyl alcohol. The isoxazoline ligands were found to be essential to promote the cyclization.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 595 - 604
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DOI: 10.3987/COM-02-S58
Stereoselective Synthesis of the Optically Pure AB-Ring Moiety of Trichothecene Sesquiterpene (+)-Calonectrin

Akira Iida, Kazuhide Konishi, Hironobu Matsumoto, Masafumi Kaneko, and Kiyoshi Tomioka*

*Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-machi, Sakyo-ku, Kyoto 606-8501, Japan


The optically pure trichothecene cis-AB ring moiety (1) was synthesized starting from an optically pure butenolide (7) through the ring closing olefin metathesis for the formation of the A-ring and a Lewis acid mediated cyclization to the cis-fused tetrahedrochromane skeleton that had been converted to natural trichothecene, (+)-calonectrin.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 605 - 611
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DOI: 10.3987/COM-02-S59
Rhodium-catalyzed Asymmetric 1,4-Addition of 3-Thiopheneboronic Acid to α,β-Unsaturated Carbonyl Compounds

Kazuhiro Yoshida and Tamio Hayashi*

*Department of Chemistry, Gradauate Schol of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan


Asymmetric 1,4-addition of 3-thiopheneboronic acid to α,β-unsaturated carbonyl compounds proceeded with high enantioselectivity in the presence of 3 mol% (Rh) of [Rh(OH)((S)-binap)]2 in dioxane/H2O (10/1) at 40 °C to give the corresponding optically active β-(3-thienyl) carbonyl compounds of over 94% ee.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 613 - 622
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DOI: 10.3987/COM-02-S62
Photochemical Identification of the Binding Region for (S)-Semotiadil on Sodium Channels: Comparison with that for (R)-Semotiadil on Skeletal Muscle Calcium Channel

Hiromi Yoshikawa, Eisuke Shimizu, Kohichi Kawahara, Akihiko Kuniyasu, Toshiro Shibano, and Hitoshi Nakayama*

*Department of Biofunctional Chemistry, Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862-0973, Japan


To clarify the recognition site of (S)-semotiadil in the Na+ channels, we employed photoaffinity labeling with (S)-[3H]-D51-4700, an azidophenyl derivative of (S)-semotiadil, to Na+ channel preparations from rat brains and porcine hearts, and the results were compared with those by (R)-enantiomer to skeletal muscle Ca2+ channel. Protease-digestion of the photolabeled Na+ channels followed by quantitative immunoprecipitation assay using a site-directed antibody, revealed that 10- and 13- kDa fargments of brain and cardiac Na+ channels, respectively, were located within the regions including IVS6. These regions are corresponding to the 8.3 kDa fragment photolabled by (R)-[3H]-D51-4700 in the skeletal muscle Ca2+ channel. Interestingly, however, the photoincorporation of (S)-[3H]-D51-4700 into the Na+ channel was 2-3 times higher than that of (R)-isomer; and visa versa in the Ca2+ channels.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 623 - 633
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DOI: 10.3987/COM-02-S63
Synthesis of the Amide Analog of Alternariolide (AM-Toxin I), a Host Specific Phytotoxin for Apple Leaves

Mitsuru Sakai, Toshikatsu Okuno, Kimiko Hashimoto,* and Haruhisa Shirahama*

*School of Science, Kwansei Gakuin University, 1-1-155 Uegahara, Nishinomiya 662-8501, Japan


The amide analog of alternariolide (AM-toxin I) was synthesized with high efficiency. The analog showed comparable biological activity to that of alternariolide.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 635 - 643
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DOI: 10.3987/COM-02-S65
A New Chiral Pyrrolidine- and Pyrrolidinoneethanols for Enantioselective Addition of Diethylzinc to Arylaldehydes

Yuko Okuyama, Hiroto Nakano,* Mayumi Igarashi, Chizuko Kabuto, and Hiroshi Hongo

*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan


New chiral pyrrolidineethanols and unusual type of pyrrolidinoneethanol fused bicyclo[2.2.2]octane ring systems as backbones were synthesized and were used to the addition of diethylzinc to aromatic aldehydes to afford the secondary aryl alcohols leading to enantioselectivities up to 94% ee.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 645 - 659
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DOI: 10.3987/COM-02-S67
Structures of Two New Highly Oxygenated Labdane-Type Diterpenoids and a New Cadinane-Type Sesquiterpenoid Possessing a Cyclic Ether Linkage from the Liverwort Ptychanthus striatus

Toshihiro Hashimoto, Shigeru Takaoka, Masami Tanaka, and Yoshinori Asakawa*

*Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-machi, Tokushima, 770-8514, Japan


As a part of our systematic investigation of biologically active substances of liverworts, we studied the chemical constituents of the liverwort Ptychanthus striatus belonging to the Lejeuneaceae family, and isolated two novel labdane-type diterpenoids, named ptychantins J and K, and a new cadinane-type sesquiterpene possessing a cyclic ether linkage. Their relative structures were determined by a combination of high resolution NMR spectrometry, X-Ray crystallographic analysis and chemical degradations.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 661 - 668
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DOI: 10.3987/COM-02-S71
Nitrogen Fixation Using Titanium Complex: Reinvestigation of the Reaction Conditions

Masaya Akashi and Miwako Mori*

*Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan


The amounts of Li and TMSCl of a TiX4-Li-TMSCl system for a nitrogen fixation method, previously reported by our group, were examined. As the results, the reactivity of titanium-nitrogen complexes prepared from 4 equiv. of Li and 6 equiv. of TMSCl for Ti(OPr-i)4 (1 equiv.) under an atmosphere of nitrogen was same as that of titanium-nitrogen complexes reported previously.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 669 - 684
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DOI: 10.3987/COM-02-S77
The Photodecarboxylative Addition of Carboxylates to Phthalimides: Scope and Limitations

Michael Oelgemöller, Peter Cygon, Johann Lex, and Axel G. Griesbeck*

*Institute of Organic Chemistry, University of Cologne, Greinstrasse 4, D-50939 Köln, Germany


Intermolecular photoinduced decarboxylative additions of a series of alkylcarboxylates to N-substituted phthalimides gave the corresponding hydroxy-phthalimidines in moderate to high yields of 39-89%. The potassium salt of 1- adamantanecarboxylic acid predominately underwent simple decarboxylation when irradiated in the presence of N-methylphthalimide. In case of phthalimides carrying suitable leaving groups within the N-side chain, decarboxylation, retro-Aldol cleavage or decarbonylation preceded the intermolecular addition step.

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Paper | Special issue | Vol 59, No. 2, 2003, pp. 685 - 690
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DOI: 10.3987/COM-02-S78
Preparation of 7-Substituted 4,5-Dihydro-7H-Pyrano[3,4-c]isoxazole Derivatives

Koji Yamada, Fumio Yamada, and Masanori Somei*

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan


An easy approach to 7-substituted 4,5-dihydro-7H-pyrano[3,4-c]isoxazole derivatives (3a-b and 6a-d) is described by the reaction of 2-aryl substituted 1-nitro-3-oxa-6-heptynes (2, 5a and 5b) with n-BuLi, followed by treatment with acetic anhydride.

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43 data found. 1 - 30 listed Next Last