Special Issue

Edward C. Taylor's Special Issues, Vol. 35, No. 2, 1993

97 data found. 1 - 30 listed Next Last
Communication | Special issue | Vol 35, No. 2, 1993, pp.559-562
Published online:
DOI: 10.3987/COM-92-S(T)46
γ-Cyclodextrins Bearing a Pyrenylamide Moiety. The Effect of Photoexcited-State Acid-Base Equilibrium of Appended Chromophone on Their Guest Binding

Iwao Suzuki, Yoshinobu Sakurai, Masahiro Ohkubo, Maki Ito, Tetsuo Osa,* and Akihiko Ueno

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

Abstract

γ-Cyclodextrins bearing a pyrenylamide moiety at primary or secondary hydroxyl side (1 and 2, respectively) showed red-shifted fluorescence as well as normal fluorescence in a solution of pH below 3. This red-shifted fluorescence was emitted from the pyrenylamide moiety protonated in the excited state. Guest binding ability of 2 was markedly affected by the protonation, while that of 1 was hardly affected.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.563-568
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DOI: 10.3987/COM-92-S(T)47
Synthesis of Cyclopentadienyl-ene-1,2-dithiolatocobalt Complexes and Coupled Proton-Electron Transfer in a Substituted Quinaxalinyl Derivative

Elaine M. Armstrong, Michael S. Austerberry, Jacqueline H. Birks, Roy L. Beddoes, Madeleine Helliwell, John A. Joule, and C. David Garner*

*Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, U.K.

Abstract

A series of cyclopentadienyl-ene-1,2-dithiolatocobalt complexes, [(η5-C5H5)Co(S2C2RH)], has been prepared. The derivative in which quinoxalin-2-yl is bound to the dithiolene manifests novel electrochemical behaviour in acidic media which is consistent with a coupling of metal-centered electron addition to protonation of a pyrazine ring nitrogen.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.569-572
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DOI: 10.3987/COM-92-S(T)55
Photocycloaddition of 2'-Deoxyribonuculeoside to 2,3-Dimethly-2-butene

Naoki Haga, Ichiro Ishikawa, Masaya Kinumura, Hiroaki Takayanagi, and Haruo Ogura*

*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan

Abstract

Photosensitized cycloaddition of 2,3-dimethyl-2-butene to 2’-deoxyuridine, thymidine and 5-fluoro-2’-deoxyuridine by the uv irradiation in acetone have been studied. From the respective reactant, a pair of diastereomers which has a cyclobutane ring were formed. However in each reaction one of the two isomers could be isolated and purified by recrystallization.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.573-576
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DOI: 10.3987/COM-92-S(T)60
An Effecient Synthesis of 2-Aroly-1H-indoles

Yohko Takeda, Akiko Kikuchi, and Masanao Terashima*

*Faculty of Pharmaceutical Scicences, Higashinihonngakuen University, 1757 Kanazawa, Toubetu-cho, Ishikari-gun, Hokkaodo 061-0212, Japan

Abstract

2-Aroyl-1H-indoles were directly obtained by the reaction of 1-(N-aroylcarbamoyl)indoles, prepared from 1-(2-oxazolinyl)indole and aroyl chlorides, with LDA.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.577-580
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DOI: 10.3987/COM-92-S(T)62
Stereoselective Synthesis of Diamino Diol Derivaties with C2-Axis of Symmetry

Tsutomu Yokomatsu, Kenjio Suemune, and Shiroshi Shibuya*

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

Abstract

An efficient and stereocontrolled synthesis of C2-symmetric diamino diol derivatives (7) was achieved through selective opening of N-Boc bis-aziridine (6), prepared from D-mannitol via cyclic sulfate(4).

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Communication | Special issue | Vol 35, No. 2, 1993, pp.581-583
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DOI: 10.3987/COM-92-S(T)67
Vicarious Nucleophilic Substitution of 1,2,3-Triazines

Takashi Itoh, Kazuhiro Nagata, Mamiko Okada, and Akio Ohsawa*

*School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan

Abstract

Vicarious nucleophilic substitution of 1,2,3-triazinium 2-dicyanomethylides with 1-chloromethyl phenyl sulfone proceeded to give corresponding 5-substituted derivatives. Dicyanomethylene group was readily eliminated by radical reaction to afford 5-phenylsulfonylmethyl-1,2,3-triazines.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.585-589
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DOI: 10.3987/COM-92-S(T)69
A Unified Synthetic Strategy for Elaboration of the DEF Tricyclic Subunit Common to the Austalide Mycotoxins

Leo A. Paquette* and Matthias M. Schulze

*Evans Chemical Laboratories, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210, U.S.A.

Abstract

Tricycle (19), representing the DEF subunit common to all known austalide mycotoxins, has been economically synthesized from 2,3-dihydropyran in 8 steps via several highly stereo- and regioselective transformations.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.591-598
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DOI: 10.3987/COM-92-S(T)70
1,3-Dipolar Cycloaddition Reactions Involving Captodative Olefins

Rogelio Jiménez, Lucelia Pérez, Jaoquín Tamariz, and Hector Salgado*

*Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, I. P. N., Prol. Carpio y Plan de Ayala S/N,11340, Mexico, D.F.

Abstract

A series of arylnitrile oxides (6a-e) were reacted with captodative olefins (4) to yield 5-acetyl-3-arylisoxazoles. No intermediate isoxazolines were formed, the olefins thus behaved as acetylene equivalents. A plausible explanation for the observed regioselectivity in the process is offered as well.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.599-602
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DOI: 10.3987/COM-92-S(T)74
Synthesis of Pyrano[4,3-b]benzodiazepine and Pyrano[4,3-b]quinoline Using 4-Chloro-3-(1-chlorovinyl)-6-methyl-2H-pyran-2-one and 4-Chloro-3-ethynyl-6-methyl-2H-pyran-2-one

Yutaka Azuma,* Atsuko Sato, and Mieko Morone

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

Abstract

Reaction of dichloropyrone (1) and chloroethynylpyrone (2) with o-phenylenediamine and m-phenylenediamine give pyranobenzodiazepine (3) and pyranoquinoline (5), respectively. Treatment of 1 and 2 with p-phenylenediamine yield aminoethynylpyrone (6), which is a key product in the readion of 1 and 2 with phenylenediamines.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.603-606
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DOI: 10.3987/COM-92-S(T)76
Enzyme-catalyzed Synthesis of Biologically Active (S)-Nilvadipine

Hirosato Ebiike, Yumi Ozawa, Kazuo Achiwa,* Yoshihiko Hirose, Kinya Kariya, Ikuharu Sasaki, and Yoshiaki Kurono

*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan

Abstract

Optically active 2-hydroxymethyl-1,4-dihydropyridine was obtained by lipase-catalyzed transesterification of isopropyl methyl 1,4-dihydro-2-hydroxymethyl-6-methyl-4-(3-nitrophenyl)-3,5-pyridinecarboxylate. This chiral dihydropyridine was readily converted into biologically active (S)-nilvadipine.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.607-610
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DOI: 10.3987/COM-92-S(T)78
Isolation of (-)-Preorixine, a Postulated Biosynthetic Key Intermediate of (+)-Orixine and Related Quinoline Alkaloids, from the Stems of Orixa japonica

Shinji Funayama, Takahiro Kageyama, Kiyoshi Murata, Michiko Adachi, and Shigeo Nozoe*

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

Abstract

A prenyl quinoline alkaloid (-)-preorixine was isolated from the stems of Orixa japonica (Rutaceae) and its structure was elucidated to be (-)-3-(2S,3-epoxy-3-methylbutyl)-2,4-dimethoxy-7,8-methylenedioxyquinoline. (-)-Preorixine is postulated as a biosynthetic key intermediate of (+)-orixine and related compounds.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.611-613
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DOI: 10.3987/COM-92-S(T)79
Formation of Oxygen Heterocycles from Alkynes Catalyzed by Ru3(CO)12

Naim Menashe and Youval Shvo*

*School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv university, Tel Aviv, 69978, Israel

Abstract

When dimethyl acetylenedicarboxylate and 2-cyanophenylphenylacetylene were each reacted with acetic acid under catalysis of Ru3(CO)12, 2,3,4-tricarbomethoxy-α-pyrone (1) and 3-phenylisocoumarin (3) were formed in good yields.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.615-618
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DOI: 10.3987/COM-92-S(T)81
The Stereoselective Hydrogenation of Nepetalactoles. The Role of C1 Alkoxyl Groups on the Stereoselectivity

Masaharu Kigawa, Masahide Tanaka, Takao Katsuhara, Koh Sugama, Masao Maruno, Hiroshi Mitsuhashi, and Takeshi Wakamatsu*

*Tsumura Reserach Institute for Biology and Chemistry (TRIBIC), 3586 Yoshiwara, Ami-machi, Inashiki-gun, Ibaraki 300-1192, Japan

Abstract

The stereoselective hydrogenation of nepetalactol and its derivatives was examined. From the stereochemical outcome and the conformational analyses of starting materials, it was concluded that, in the hydrogenation of nepetalactols, the most important factor which determined the steric course of reaction is the configuration of C1 position which carries the alkoxyl group.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.619-622
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DOI: 10.3987/COM-92-S(T)82
Synthesis of 3-Hydroxy-2,3,4,5-tetrahydro-1,5-benzothiazepines

Michinori Karikomi, Shouzou Yamori, and Takashi Toda*

*Department of Applied Chemistry, Faculty of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya 321-8585, Japan

Abstract

New general synthetic methods of benzothiazepine derivatives were studied. Treatment of 2-(1-haloalkyl)oxiranes (1) with 2-aminothiophenol in the presence of a base provides a variety of benzothiazepine derivatives (4) in excellent yields. The reaction is assumed to proceed through cyclization of an oxirane intermediate (3).

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Communication | Special issue | Vol 35, No. 2, 1993, pp.623-626
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DOI: 10.3987/COM-92-S(T)83
Selective Sinthesis of Five and Six Membered Cyclic Carbamates by the Reaction of 2-(1-Haloalkyl)oxiranes with Carbon Dioxide and Aliphatic Primary Amines

Masaaki Yoshida, Masabumi Ohshima, and Takashi Toda*

*Department of Applied Chemistry, Faculty of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya 321-8585, Japan

Abstract

The reaction of 2-(1-haloalkyl)oxiranes with carbamate salts selectively gave perhydrooxazin-2-ones at neutral conditions and oxazolidin-2-ones at basic. Those reactions proceeded stereospecifically and the mechanisms were discussed.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.627-630
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DOI: 10.3987/COM-92-S(T)94
Stereoselective Synthesis of Highly Functionalized γ-Lactones via Iodolactonization

Manfred T. Reetz* and Erik H. Lauterbach

*Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 4330 Mülheim/Ruhr, Germany

Abstract

Chiral γ-amino α,β-unsaturated carboxylic acids (5) derived from L-amino acids undergo diastereofacially selective iodolactonization with formation of the highly functionalized lactones (7).

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Communication | Special issue | Vol 35, No. 2, 1993, pp.631-634
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DOI: 10.3987/COM-92-S(T)99
Theoretical Study of Mechanism and Stereoselectivity of the Ring Opening of Formyloxirane

Kensuke Nakamura and Kendall N. Houk*

*Department of Chemistry and Biochemistry, University of California, 405 Hilgard Avenue, Los Angels, CA 90024, U.S.A.

Abstract

The stereochemistry and reaction mechanism of the thermal ring opening of formyloxirane and subsequent cyclization were studied by using the ab initio molecular orbital calculations. Stationary points along lowest energy pathways, including the unstable carbonyl ylide intermediate were located.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.635-638
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DOI: 10.3987/COM-92-S(T)101
β-Lactam Formation via Enolate Addition: An Unexpected Methylenation Reaction

Maghar S. Manhas,* Ashok G. Chaudhary, Vegesna S. Raju, Ernest W. Robb, and Ajay K. Bose

*Department of Chemistry and Chemical Engineering, Stevens Institute of Technology, Castle Point on the Hudson, Hoboken, NJ 07030, U.S.A.

Abstract

The condensation of ethyl phenylacetate or ethyl β-hydroxyburyrate with Schiff bases in presence of an excess of lithium diisopropylamide or lithium hexamethyldisilazide leads to unsaturated amides instead of the expected β-lactams.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.639-642
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DOI: 10.3987/COM-92-S(T)103
Highly Regioselective Alkylation of Pteridine

Shizuaki Murata,* Kenji Kiguchi, and Takashi Sugimoto

*Laboratories of Biophysics and Bioorganic Chemistry, Graduate School of Human Informatics, Nagoya University, Chikusa, Nagoya 464-8601, Japan

Abstract

Reaction of 2-amino-4-butoxypteridine with a Grignard reagent or an alkyllithium followed by iodine oxidation gives the 7-substituted pteridine, regioselectively.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.643-647
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DOI: 10.3987/COM-92-S(T)105
A Practical Prepraration of Δ1-2-Substituted and Δ1-2,3-Disubstituted Pyrrolines

Mark L. Haslego, Cynthia A. Maryanoff, Lorraine Scott, and Kirk L. Sorgi*

*Chemical Development Department, The R. W. Johnson Pahramceutical Research Institute, Spring House, PA 19477-0766, U.S.A.

Abstract

Addition of N-vinylpyrrolidinone and an ester to NaH in THF effects acylation and affords keto lactams (1) in high yields. Hydrolysis of 1 in strong acid generates Δ1-2-substituted pyrrolines (2) in good yield. Keto lactams (1) can be further alkylated and hydrolyzed to produce Δ1-2,3-disubstituted pyrrolines (4) in good isolated yield.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.649-657
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DOI: 10.3987/COM-92-S(T)106
Mechanism and Stereochemical Implications of the Reaction of an Oxazolium-5-oxide with 1,2-Dicyanocyclobutene. An AM1 Study

Cynthia A. Maryanoff and Ignatius J. Turchi*

*Chemical Development Department, The R. W. Johnson Pahramceutical Research Institute, Raritan, NJ 08869, U.S.A.

Abstract

Oxazolium-5-oxide (1) cycloadds to 1,2-dicyanocyclobutene (2) to give the imino-acid (3) and the dihydroazepine (4). AM1 molecular orbital calculations were carried out on the reaction in order to rationalize the observed stereochemistry of 3 and to further elucidate the overall reaction mechanism leading to 3 and 4.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.659-664
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DOI: 10.3987/COM-92-S(T)108
Preparation of 3,4-Diaryl-4,5-dihydro-1H-1,2,4-triazole-1-N-phenylcarboxamides

Donald J. Dumas*

*Du Pont Agricultural Products, E. I. du Pont Nemours Company, Delaware 19898, U.S.A.

Abstract

N3-Arylbenzamidrazone (5) reacts with aldehydes and ketones to give the corresponding hydrazones (6) rather than the tautomeric 4,5-dihydro-1H-1,2,4-triazoles (7). Treatment of the hydrazones (6) with α,α,α-trifluoro-p-tolyl isocyanate gives 3,4-diaryl-4,5-dihydro-1H-1,2,4-triazole-1-carboxamides (8). This suggests that, in solution, hydrazones (6) exist in equilibrium with low levels of the more nucleophilic 4,5-dihydro-1H-1,2,4-triazoles (7) which are trapped by isocyanate to give triazolines of formula (8).

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Communication | Special issue | Vol 35, No. 2, 1993, pp.665-669
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DOI: 10.3987/COM-92-S(T)114
Reaction of Diols and Triols with Trialkyl Orthoesters: Facile One-Pot Formation of Oxacyclic Compounds from Triols

Hiromichi Fujioka, Hidetoshi Kitagawa, Michinori Kondo, Naoki Matsunaga, Shinji Kitagaki, and Yasuyuki Kita*

*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan

Abstract

Reaction of diols and triols with trialkyl orthoesters was studied and facile one-pot formation of oxacyclic compounds from triols was developed.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.671-674
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DOI: 10.3987/COM-92-S(T)116
Chelation Controlled Nucleophilic Addition of Tetronic Acid Dianion to Aldimines: Towards the Stereoselective Construction of β-Amino Alcohols

Toshio Honda,* Tomohisa Hayakawa, Toshio Yamada, Hirotsune Kondoh, and Hiromasa Nagase

*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

Nucleophilic addition reaction of tetronic acid dianion, derived from tetronic acid with lithium diisopropylamide, to aldimines was found to proceed in a stereoselective manner providing syn adducts predominantly via the six-membered chelation transition states.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.675-678
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DOI: 10.3987/COM-92-S(T)122
Metal Binding by the Trisoxazole Portion of the Marine Natural Product Dihydrohalichondramide

D. Martin James, Edward Wintner, D. John Faulkner, and Jay S. Siegel*

*Department of Chemistry (D-006), University of California, San Diego, La Jolla, CA 92093-0682a, U.S.A.

Abstract

Metal binding to the oxazole portion of dihydrohalichondramide (1), trisoxazole (2), and diphenyloxazole (3) are studied by fluorescence quenching and nmr techniques. The trisoxazole conformation is modeled by semiempirical computations. 1-3 are found to be relatively weak binders which do not exhibit a significant chelate effect. The biological action of 1 is not related to metal binding.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.679-682
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DOI: 10.3987/COM-92-S(T)127
New Synthesis of Piperidine Derivatives via the Chromacyclobutane

Susumu Watanuki and Miwako Mori*

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

Abstract

Piperidine derivatives were synthesized from the enynes and Fischer chromium carbene complex via chromacyclobutanes in moderate yields and the reaction course was controlled by the substituents on the double bond of the enynes.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.683-687
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DOI: 10.3987/COM-92-S(T)129
An Unusual Synthesis of Nicotinamides

Philip M. Harrington*

*American Cyanamid Company, Agricultural Research Division, P. O. Box 400, Princeton, NJ 08543-0400, U. S. A.

Abstract

Reaction of 2,3-pyridinedicarboxylic anhydride (1) with a substituted aniline (2) in acetic acid gave rise to a mixture of two products. These two products were identified as the cyclic imide (4) and nicotinamide (5). A mechanistic scheme consistent with empirical observations is proposed.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.689-692
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DOI: 10.3987/COM-92-S(T)130
Directed 2-Metalation of N,N-Diethyl O-3-(4-Trimethylsilyl)pyridyl Carbamate. A Silicon Protection Route for Highly Substituted Pyridines

Masao Tsukazaki and Victor Snieckus*

*Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada

Abstract

LiTMP metalation of N,N-diethyl O-3-(4-trimethylsilyl)pyridyl carbamate (4) followed by quenching with a number of carbon and heteroatom electrophiles affords a variety of 2-substituted derivatives (5) (Table 2) thus providing a versatile new methodology for the synthesis of polysubstituted pyridines.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.693-699
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DOI: 10.3987/COM-92-S(T)131
Synthesis of 2,3-Fused Quinolines from 3-Substituted Quinoline 1-Oxides. Part III. Intramolecular Cyclization of Quinoline 1-Oxides Bearing Active Methylene Groups at the 3-Position in the Presence of Acetic Anhydride

Yutaka Miura,* Yasuo Fujimura, Sakae Takaku, and Masatomo Hamana

*Exploratory Laboratories, Chugai Pharmaceutical Company, Ltd., 1-135 Komakado, Gotemba, Shizuoka 412-835, Japan

Abstract

3-N-Alkylcyanoacetamidoquinoline 1-oxides (3a and 3c) react with Ac2O at room temperature in chloroform to afford 1-alkyl-3-cyano-4H-pyrrolo[3,2-b]quinolin-2-ones (4a and 4c). The cyclization of 3-N-alkylethoxycarbonylacetamidoquinoline 1-oxides (3b and 3d) occurs upon heating with Ac2O at 60°C. 3-(3,3-Dicyanopropoxy)quinoline 1-oxide (5) also cyclizes to the pyranoquinoline (6) when treated with Ac2O at room temperature in chloroform-DMF.

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Communication | Special issue | Vol 35, No. 2, 1993, pp.701-706
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DOI: 10.3987/COM-92-S(T)134
Onium Ions are not on the Reaction Coordinate in the Formation of Heterocycles via Electrophile-induced Alkenol Cyclizations

James Sperka and Dennis C. Liotta*

*Department of Chemistry, Emory University, 1521 Pierce Drive Atlanta, Georgia 30322, U.S.A.

Abstract

Semi-empirical molecular orbital methodology was used to determine the reaction surfaces for competitive intramolecular bromoetherification and intermolecular bromohydrin reactions. These reactions do not proceed through a bromonium ion intermediate. Instead, the additions involve the formation of a weak olefin / Br+ Π-complex which is subsequently captured by a proximate nucleophile.

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97 data found. 1 - 30 listed Next Last