Special Issue

Leo A. Paquette's Special Issues, Vol. 62, No. 1, 2004

78 data found. 61 - 78 listedFirst Previous
Paper | Special issue | Vol 62, No. 1, 2004, pp.749-756
Published online: 17th November, 2003
DOI: 10.3987/COM-03-S(P)73
Acid-catalyzed Cyclization Reactions of 2,2’-Bis(diarylhydroxymethyl)biphenyls to 5,5,7,7-Tetraaryl-5,7-dihydrodibenzo[c,e]oxepins in the Solid State

Shinya Hirano, Shinji Toyota, and Fumio Toda*

*Department of Chemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan

Abstract

Heating of 2:1 inclusion crystals of 2,2’-bis(hydroxydiphenylmethyl)biphenyl and formic acid in the solid state gave 5,5,7,7-tetraphenyl-5,7-dihydrodibenzo[c,e]oxepin in 89% yield. When mixtures of 2,2’-bis([bis(p-methoxyphenyl)hydroxymethyl]biphenyl and p-toluenesulfonic acid in 2:1 and 1:0.1 molar ratios were kept at room temperature for 80 min and 12 h, respectively, 5,5,7,7-tetra(p-methoxyphenyl)-5,7-dihydrobenzo[c,e]oxepin was obtained in quantitative yields. These are the first examples of an acid-catalyzed reaction in the solid state.

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Paper | Special issue | Vol 62, No. 1, 2004, pp.757-772
Published online: 18th November, 2003
DOI: 10.3987/COM-03-S(P)74
Reactions of 2-, 3-, and 4-Quinolinols with Cyclohexane and Benzene in Superacids

Konstantin Yu. Koltunov, G. K. Surya Prakash,* Golam Rasul, and George A. Olah*

*Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, U.S.A.

Abstract

Isomeric 2-, 3- and 4-quinolinols (11-13) underwent selective ionic hydrogenation with cyclohexane in CF3SO3H-SbF5 system to give 5,6,7,8-tetrahydro-2(1H)-quinolinone, 5,6,7,8-tetrahydro-3-quinolinol and 5,6,7,8-tetrahydro-4(1H)-quinolinone (28-30), respectively. When reaction was carried out in the presence of excess of aluminum chloride, 11 gave 3,4-dihydro-2(1H)-quinolinone (31), whereas 13 gave the product (30). Compounds (11) and (13) condense with benzene in the presence of aluminum halides producing phenyl substituted derivatives of 28, 31 and 30 (products 32-34), respectively. The mechanism of these and related reactions involving superelectrophilic dicationic intermediates is discussed.

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Note | Special issue | Vol 62, No. 1, 2004, pp.773-778
Published online: 14th October, 2003
DOI: 10.3987/COM-01-9286
[2π+2σ] Type Cycloaddition Reactions of Naphtho[b]cyclopropene with Trithiocarbonyl Compounds to Form 1,3-Dihydronaphtho[2,3-c]thiophene Derivatives

Katsuhiro Saito,* Yasuhiro Ohzone, Yoji Kondo, Katsuhiko Ono, and Masakazu Ohkita

*Department of Applied Chemistry, Faculty of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Abstract

Reactions of naphtho[b]cyclopropene with trithiocarbonyl derivatives in chloroform afforded 1,3-dihydrobenzo[2,3-c]thiophene derivatives in moderate yields through a [2π + 2σ] type cycloaddition process. The similar reaction with a dithiocarbonate compound gave a recovery of the starting material. A reaction with thiotropone resulted in a [8π + 2σ] type adduct in 5% yield. Solvent effects on the product yields revealed that the reactions proceeded via ionic intermediates.

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Note | Special issue | Vol 62, No. 1, 2004, pp.779-786
Published online: 28th April, 2003
DOI: 10.3987/COM-03-S(P)3
A Novel, Expedient Synthesis of Thiazolo[4,5-c]- and -[5,4-b]carbazoles

Manas Chakrabarty,* Nandita Ghosh, and Yoshihiro Harigaya

*Department of Chemistry, Bose Institute, 93/1, A. P. C. Road, Kolkata-700009, India

Abstract

A new synthesis of thiazolo[4,5-c]- and -[5,4-b]carbazoles (6a-e, 7a, 8b-e) was accomplished from 3-aminocarbazoles (3a-e) by separate condensations with methyl and phenyl isothiocyanates, followed by oxidative cyclization of the resulting thioureidocarbazoles (4a-e, 5a).

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Note | Special issue | Vol 62, No. 1, 2004, pp.787-792
Published online: 28th April, 2003
DOI: 10.3987/COM-03-S(P)4
A Formal Total Synthesis of (-)-Limaspermine

Yu-ichi Fukuda, Mitsuru Shindo, and Kozo Shishido*

*Institute for Medicinal Resources, University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505, Japan

Abstract

An enantiocontrolled formal total synthesis of an aspidosperma indole alkaloid (-)-limaspermine has been accomplished using a diastereoselective ring-closing metathesis for formation of the quaternary stereogenic center.

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Note | Special issue | Vol 62, No. 1, 2004, pp.793-802
Published online: 6th October, 2003
DOI: 10.3987/COM-03-S(P)9
The Fungicidal Benzothiazole Methoxyacrylates: Synthesis, Conformational Analysis and Fungicidal Activity

Choon Sup Ra,* Bon Young Jung, and Gyoosoon Park*

*Department of Chemistry, Yeungnam University, Kyongsan 712-749, Korea

Abstract

Synthesis of a series of novel benzothiazole methoxyacrylate compounds (3-4) based on the antifungal natural product, Strobilurin A is described. Fungicidal activities of 3-4 against six representative fungal diseases and their comparative conformational analyses vs Strobilurin A are accounted.

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Note | Special issue | Vol 62, No. 1, 2004, pp.803-806
Published online: 14th October, 2003
DOI: 10.3987/COM-03-S(P)19
Concise Synthesis of 11H-Indolizino[1,2-b]quinolin-9-one by an Aryl-Aryl Coupling Reaction Using Pd Reagent

Takashi Harayama,* Yosiaki Morikami, Akihiro Hori, Hiromi Nishioka, Hitoshi Abe, and Yasuo Takeuchi

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

Abstract

The biaryl coupling reaction of 1-[(2-bromoquinoline-3-yl)methyl]-2(1H)-pyridinone using a catalytic amount of palladium acetate, tricyclohexylphosphine, and potassium acetate in DMF proceeded smoothly to give 11H-indolizino[1,2-b]quinolin-9-one in excellent yield.

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Note | Special issue | Vol 62, No. 1, 2004, pp.807-813
Published online: 27th October, 2003
DOI: 10.3987/COM-03-S(P)26
An Efficient Preparative Route to 7-Ethyl-1H-furo[2,3-g]indazole

Itsuro Shimada,* Kyoichi Maeno, Tetsuya Kimizuka, Seiki Goto, Takumi Takahashi, Atsushi Nakamura, Akio Miyafuji, Shin-ichi Tsukamoto, and Shuichi Sakamoto

*Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21, Miyukigaoka, Ibaraki 305-8585, Japan

Abstract

A new and efficient route to 7-ethyl-1H-furo[2,3-g]indazole (2) has been developed. Treatment of 4,5-dihydro-7-(1-hydroxyethyl)indazole (12) with hydrochloric acid in ethanol resulted in a concomitant dehydration and aromatization to afford the title compound in good yield.

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Note | Special issue | Vol 62, No. 1, 2004, pp.815-819
Published online: 27th October, 2003
DOI: 10.3987/COM-03-S(P)27
Regioselective Synthesis of 6- and 7-Substituted Thiazolo[3,2-a]benzimidazole Derivatives Using Crystallization Induced Regioisomerization

Satoshi Hayashibe,* Takashi Kamikubo, Shin-ichi Tsukamoto, and Shuichi Sakamoto

*Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21, Miyukigaoka, Ibaraki 305, Japan

Abstract

An efficient regioselective synthesis of 2-methoxycarbonylthiazolo[3,2-a]benzimidazole-6-carboxylic acid (2) and 2-methoxycarbonylthiazolo[3,2-a]benzimidazole-7-carboxylic acid (3) have been developed.

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Note | Special issue | Vol 62, No. 1, 2004, pp.821-826
Published online: 14th November, 2003
DOI: 10.3987/COM-03-S(P)38
Synthesis and Properties of Azaperylenedicarboximide Derivative

Yukinori Nagao,* Eri Shimokoshi, and Kozo Kozawa

*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan

Abstract

Azaperylenedicarboximide derivative was prepared by coupling of N-pentyl-4-tributylstannylnaphthalene-1,8-dicarboximide with 4-bromo-1,8-dimethylisoquinoline in the presence of Pd(PPh3)4 and following ring closure reaction by using t-C4H9OK/DBN as base. Spectral properties of absorption and fluorescence in solution of the azaperylene derivative were investigated.

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Note | Special issue | Vol 62, No. 1, 2004, pp.827-830
Published online: 27th October, 2003
DOI: 10.3987/COM-03-S(P)45
Cyclofunctionalization of Unsaturated Alcohols, Phenols, Acids, and Sulfonamides with 1-Benzenesulfinyl Piperidine and Trifluoromethanesulfonic Anhydride

David Crich,* Bhushan Surve, and Mousumi Sannigrahi

*Department of Chemistry, University of Illinois at Chicago, 845 West Taylor St., Chicago, IL 60607-7061, U.S.A.

Abstract

The combination of a benzenesulfinamide, trifluoromethanesulfonic anhydride, and Hünig’s base brings about the cyclofunctionalization of unsaturated alcohols, phenols, acids, and sulfonamides to give the corresponding α-phenylsulfanylmethyl cyclic ethers, lactones and sulfonamides, respectively. In an unanticipated twist the products are isolated at the sulfur (II) oxidation state denoting an overall reduction in the oxidation state of the sulfur based electrophile in the course of the reaction.

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Note | Special issue | Vol 62, No. 1, 2004, pp.831-838
Published online: 14th November, 2003
DOI: 10.3987/COM-03-S(P)60
Spiro Bis(isoxazole) as a New Chiral Ligand

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

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

Abstract

A novel bis(isoxazole) ligand, (M*)-4,4’,5,5’,6,6’,7,7’-octahydro- 7,7’-spirobi[benzo[c]isoxazole] (5) bearing a spiro chirality was designed and synthesized. Characterization of the ligand and its application to the enantioselective tandem cyclizaton of alkenyl alcohol via oxy-palladation are described.

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Note | Special issue | Vol 62, No. 1, 2004, pp.839-846
Published online: 14th November, 2003
DOI: 10.3987/COM-03-S(P)63
New Access to Chiral Cyclic ω-Oxygenated β-Enamino Esters by Intramolecular Aminocyclisation Reactions

Olivier David, Corinne Vanucci-Bacqué, Marie-Claude Fargeau-Bellassoued, and Gérard Lhommet*

*Laboratoire de Chimie des Hétérocycles UMR 7611, Université P. et M. Curie, case courrier 43, 4 Place Jussieu, F-75252 Paris Cedex 05, France

Abstract

The preparation of chiral 4-methoxycarbonylmethylideneoxazolidines and oxazolidinone from (S)-1-phenylethylamine and hydroxy alkynoates is described. The extension of this strategy to 6- and 7-membered heterocyclic homologues is also reported.

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Note | Special issue | Vol 62, No. 1, 2004, pp.847-849
Published online: 14th November, 2003
DOI: 10.3987/COM-03-S(P)65
Reductive Methylation/Phosphorylation of 3,4-Diazacyclopentadienone N-Oxides with Trimethyl Phosphite

Jeremiah P. Freeman* and Marc E. Guay

*Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN 46556, U.S.A.

Abstract

Treatment of 2,5-diphenyl-3,4-diazacyclopentadienone 3-oxide and 3,4-dioxide with trimethyl phosphite results in N-deoxygenation and methylation and O-phosphorylation to produce dimethyl (1-methyl-3,5-diphenyl-4-pyrazolyl) phosphate.

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Note | Special issue | Vol 62, No. 1, 2004, pp.851-856
Published online: 14th November, 2003
DOI: 10.3987/COM-03-S(P)66
A Direct Approach to the Synthesis of 5-Aryl-4-chloropyridazinone: From Microwave Assisted Catalyst Screen to Room Temperature Regio- and Chemoselective Suzuki Arylation

Yong Gong and Wei He*

*Drug Discovery, Johnson & Johnson Pharmaceutical Research & Development, L. L. C., P. O. Box 776, Welsh and McKean Rds., Spring House, PA 19477-0776, U.S.A.

Abstract

Suzuki coupling of 4,5-dichloropyridazinone with phenylboronic acid yielded the desired 4-chloro-5-phenylpyridazinone along with 4-aryl and 4,5-diaryl derivatives. An extensive microwave-assisted screen led to the identification of Pd(PEt3)2Cl2 as an ideal catalyst with superior rate and selectivity. Further optimizations provided an effective, regioselective and chemoselective arylation method at room temperature.

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Note | Special issue | Vol 62, No. 1, 2004, pp.857-868
Published online: 18th November, 2003
DOI: 10.3987/COM-03-S(P)68
Asymmetric Synthesis of Panaxydol and Its Stereoisomers

Hsi-Jung Yu, Chang-Ming Sun, Chien-Chih Chen, Tsao-Chin Wu, Chia-Ling Wei, and Chien-Chang Shen*

*National Research Institute of Chinese Medicine, 155-1, Sec. 2, Li-Nung Street, Taipei 112, Taiwan, R.O.C.

Abstract

A facile synthesis of four possible stereoisomers of panaxydol was described. The configurations of C-3 and C-9, C-10 positions were established by enantioselective reduction and Sharpless asymmetric dihydroxylation, respectively.

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Note | Special issue | Vol 62, No. 1, 2004, pp.869-876
Published online: 18th November, 2003
DOI: 10.3987/COM-03-S(P)70
Syntheses of Oxazolidinone, Imidazolidinone and Thiazolidinone Derivatives Using a Polymer-supported Diphenylphosphoryl Azide

Yuhua Lu and Richard T. Taylor*

*Department of Chemistry, Miami University, Oxford, Ohio 45056, U.S.A.

Abstract

By using a polymer-supported diphenylphosphoryl azide (PS-DPPA), oxazolidinone, imidazolidinone and thiazolidinone derivatives were successfully prepared from carboxylic acids bearing different reactive functional groups in the β position , such as alcohols, thiols, primary or secondary amines. The desired compounds were obtained in good yields via Curtius rearrangement and subsequent intramolecular cyclization.

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Review | Special issue | Vol 62, No. 1, 2004, pp.877-898
Published online: 28th April, 2003
DOI: 10.3987/REV-03-SR(P)1
Azabicyclo[2.1.1]hexanes. A Review

Grant R. Krow* and Kevin C. Cannon

*Department of Chemistry, Temple University, Philadelphia, PA 19122, U.S.A.

Abstract

The synthesis and reactions of 1-, 2-, and 5-azabicyclo[2.1.1]hexanes are reviewed.

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78 data found. 61 - 78 listedFirst Previous