Graphical Abstracts

Abstract

Synth. Commun. 2004, 34, 4243

Sulfamic Acid as a Cost‐Effective and Recyclable Catalyst for Protection of Carbonyls to Acetals and Ketals Under Mild Conditions of Alcohols over Sulfamic Acid as Reusable Catalyst

Weizhong Gong,^1,2 Bo Wang,¹ Yanglong Gu,¹ Liang Yan,¹ Liming Yang,¹ and Jishuan Suo^1,3

¹State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China

²Institute of Biology of Gansu Academy

³Chengdu Organic Chemicals Co. Ltd., Chinese Academy of Sciences, China

An efficient H₂NSO₃H‐catalyzed protection of various carbonyl compounds at room temperature was investigated. The features of mild conditions, cost‐efficient catalyst, simple workup, and the recyclability of the catalyst were represented in this process.

Abstract

Synth. Commun. 2004, 34, 4249

Ytterbium Triflate Catalyzed Friedel–Crafts Reaction: Facile Synthesis of Diaryl Ketones

Weike Su and Can Jin

College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, P.R. China

Friedel–Crafts reaction of aromatic compounds (benzenes, thiophene, furan, pyrrole, naphthalene and benzothiophene) with bis(trichloromethyl) carbonate [BTC] was efficiently catalyzed by ytterbium triflate [Yb(OTf)₃] to give diaryl ketones with moderate to good yields.

Abstract

Synth. Commun. 2004, 34, 4257

One‐Pot Synthesis of Ene‐Lactams Via N‐Debenzylation of Keto‐Containing N‐2,4‐Dimethoxylbenzylamides

Wai Ming Kan,¹ Ching‐Lung Cheng,² and Ching‐Yuh Chern²

¹Department of Pharmacology, National Cheng Kung University, Tainan, Taiwan R.O.C.

²Department of Applied Chemistry, National Chiayi University, Chiayi, Taiwan, R.O.C.

Abstract

Synth. Commun. 2004, 34, 4265

An Efficient Procedure for the Synthesis of Benzimidazole Derivatives Using Yb(OTf)₃ as Catalyst Under Solvent‐Free Conditions

Limin Wang,¹ Jia Sheng,¹ He Tian,¹ and Changtao Qian²

¹Institute of Fine Chemicals, East China University of Science and Technology, Shanghai, P. R. China

²Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, P. R. China

Abstract

Synth. Commun. 2004, 34, 4273

Bromination of Azulene Derivatives with Sodium Monobromoisocyanurate

Toshiaki Sumida,¹ Shigeru Kikuchi,¹ and Kimiaki Imafuku²

¹Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, Japan

²Department of Chemistry, Faculty of Science, Kumamoto University, Kurokami, Kumamoto, Japan

Abstract

Synth. Commun. 2004, 34, 4285

New Method for the Synthesis of 5‐Hydroxycamptothecin Derivatives

Xungui He, Heyong Gao, Wei Lu, and Junchao Cai

Shanghai Institute of Materia Medica, SIBS, Chinese Academy of Sciences, China

A facile method for the hydroxylation at C‐ring of camptothecins is described.

Abstract

Synth. Commun. 2004, 34, 4293

Gallium Triiodide Catalyzed Organic Reaction: A Convenient Synthesis of α‐Amino Phosphonates

Peipei Sun, Zhixin Hu, and Zhihao Huang

College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing, China

Abstract

Synth. Commun. 2004, 34, 4301

Direct Formation of 2,3,5‐Trichloropyridine and Its Nucleophilic Displacement Reactions in Ionic Liquid

Ping Zhong,¹ Huanan Hu,^1,2 and Shengrong Guo^1,2

¹Department of Chemistry, Wenzhou Normal College, Wenzhou, P. R. China

²Department of Chemistry, Jiangxi noraml University, Nanchang, P. R. China

The nucleophilic displacement reactions of heterocyclic compounds in ionic liquids afforded 2‐[4‐(3,5‐dihalopyridin‐2‐yloxy)‐phenoxy]‐propionates 5. R₁ = Cl, or F; 5a: R₂ = Cl, R₃ = C₂H₅; 5b: R₂ = F, R₃ = C₂H₅; 5c: R₂ = Cl, R₃ = CH₃; 5d: R₂ = F, R₃ = CH₃; 5e: R₂ = Cl, R₃ = CH₂C₆H₅; 5f: R₂ = Cl, R₃ = CH₂COC₆H₅; 5g: R₂ = Cl, R₃ = CH₂CO₂C₂H₅; 5h: R₂ = Cl, R₃ = CH₂ C≡CH.

Abstract

Synth. Commun. 2004, 34, 4313

Preparation and Stereochemistry of the Isopropylidene Derivatives of 1,2‐Dihydronaphtho[2,1‐b]Furan‐1,2‐Diol and 1,2,9,10‐Tetrahydronaphtho[2,1‐b:7,8‐b′]Difuran‐1,2,9,10‐Tetraol in Comparison with the Corresponding Acetyl Derivatives

Makoto Yamaye,¹ Yoshiko Motoyanagi,¹ Aya Nakagawa,¹ Sanae Kametani,¹ Tetsutaro Yoshinaga,² Namiko Cho (Toh),¹ Xiaobo Fan,² and Taketoshi Kito²

¹Faculty of Engineering, Kyushu Kyoritsu University, 1‐8 Jiyugaoka, Yahatanishi, Kitakyushu, Japan

²Department of Applied Chemistry, Kyushu Institute of Technology, 1‐1 Sensuicho, Tobata, Kitakyushu, Japan

Abstract

Synth. Commun. 2004, 34, 4325

An Efficient and Selective Deprotecting Method for Methoxymethyl Ethers

Yungui Peng,¹ Changyun Ji,¹ Yingchun Chen,² Chengzhi Huang,¹ and Yaozhong Jiang²

¹The School of Chemistry and Chemical Engineering, Southwest Normal University, Beibei, Chongqing, China

²Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, China

Methoxymethyl ethers were selectively deprotected to the corresponding phenols in high yields by CBr₄ and PPh₃ in aprotic solvent (ClCH₂CH₂Cl) under slightly thermal reaction conditions.

Abstract

Synth. Commun. 2004, 34, 4331

KF‐Alumina Catalyzed One‐Pot Synthesis of Pyrido[2,3‐d]Pyrimidine Derivatives

Xiang‐shan Wang,^1,2,3 Zhao‐sen Zeng,¹ Da‐qing Shi,^1,3 Xian‐yong Wei,² and Zhi‐min Zong²

¹Department of Chemistry, Xuzhou Normal University, Xuzhou Jiangsu, P. R. China

²School of Chemical Engineering, China University of Mining and Technology, Xuzhou Jiangsu, P. R. China

³The Key Laboratory of Biotechnology on Medical Plant, Xuzhou, Jiangsu, P. R. China

A series of pyrido[2,3‐d]pyrimidine derivatives were synthesized by the reaction of arylaldehyde, malononitrile, and 4‐amino‐2,6‐dihydroxylpyrimidine in ethyl alcohol at 80°C catalyzed by KF‐Al₂O₃.

Abstract

Synth. Commun. 2004, 34, 4339

Pinacol Coupling of Aromatic Aldehydes and Ketones using TiCl₃‐Al‐EtOH Under Ultrasound Irradiation

Ji‐Tai Li, Zhi‐Ping Lin, Na Qi, and Tong‐Shuang Li

College of Chemistry and Environmental Science, Hebei University; Key Laboratory of Analytical Science and Technology of Hebei Province, Baoding, P. R. China

Titanium trichloride in EtOH can be reduced by Al to the corresponding low‐valent titanium complexes. This can reduce some aromatic aldehydes and ketones to the corresponding pinacols in 40–82% yields within 30–90 min at r.t. under ultrasound irradiation.

Abstract

Synth. Commun. 2004, 34, 4349

Synthesis of Substituted 1,4‐Dihydropyridines in Water Using Phase‐Transfer Catalyst Under Microwave Irradiation

Hojatollah Salehi^1,2 and Qing‐Xiang Guo¹

¹Department of Chemistry, University of Science and Technology of China, Hefei, China

²Ministry of Science, Research and Technology, Tehran, Iran

The synthesis of various substituted 1,4‐dihydropyridines has been achieved by the reaction of aldehydes, ethyl/methyl acetoacetates, and ammonium acetate in water using phase‐transfer catalyst under microwave irradiation. Compared to the classical Hantzsch reaction conditions, this new method consistently has the advantage of good yields and short reaction times. Bifunctional compounds containing two units have been synthesized using dialdehyde as precursor in good yields.

Abstract

Synth. Commun. 2004, 34, 4359

Synthesis of Some Novel Fluorinated Pyrazolo[3,4‐b]Pyridines

S. P. Singh,¹ Rajesh Naithani,² Ranjana Aggarwal,¹ and Om Prakash¹

¹Department of Chemistry, University of Kurukshetra, Kurukshetra, Haryana, India

²Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, USA

A one‐pot procedure for synthesis of title compounds in good yield from α‐cyanoacetophenones is described.

Abstract

Synth. Commun. 2004, 34, 4369

Preparation of 3,17‐ and 3,20‐Difluoro‐Derivatives of the Androst‐5‐ene and Pregn‐5‐ene Series

Richard A. Decréau and Charles M. Marson

Christopher Ingold Laboratories, Department of Chemistry, University College London, London, UK

Abstract

Synth. Commun. 2004, 34, 4387

Ring Opening of 3‐Bromo‐2‐Isoxazolines to β‐Hydroxy Nitriles

Martin G. Kociolek and Kyle P. Kalbarczyk

Penn State Erie, The Behrend College, School of Science, Erie, PA, USA

Abstract

Synth. Commun. 2004, 34, 4395

Solvent‐Free Stereoselective Synthesis of cis‐1‐Carbomethoxy‐ 2‐Aryl‐3,3‐Dicyanocyclopropanes by Grinding

Zhongjiao Ren,¹ Weiguo Cao,^1,2 Weiyu Ding,¹ and Wen Shi¹

¹Department of Chemistry, Shanghai University, Shanghai, P. R. China

²State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, P. R. China

The novel route of high stereoselective synthesis of cis‐1‐carbomethoxy‐2‐aryl‐3,3‐dicyanocyclopropanes by grinding is described. This process is simple, efficient, and environmentally benign.

Abstract

Synth. Commun. 2004, 34, 4401

Lutetium Triflate as an Efficient and Recyclable Catalyst for Chemoselective Thioacetalization of Aldehydes

Surya Kanta De

Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue Cancer Center, Purdue University, West Lafayette, IN, USA

Abstract

Synth. Commun. 2004, 34, 4409

VO(acac)₂ Catalyzed Oxidative Deprotection of Oximes, Hydrazones, and Semicarbazones

Surya Kanta De

Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue Cancer Center, Purdue University, West Lafayette, IN, USA

Abstract

Synth. Commun. 2004, 34, 4417

Synthesis of [³H] dapsone

Judith A. Egan, Scot Pounds and Crist N. Filer*

PerkinElmer Life and Analytical Sciences Inc., 549 Albany St. Boston, Massachusetts 02118, USA

An efficient synthesis of [³H] dapsone is described.

Abstract

Synth. Commun. 2004, 34, 4421

Synthesis of 4‐(R)‐Naphthalene‐2‐Yloxy‐1‐(1‐Phenyl‐(S)‐Ethyl)‐Pyrrolidin‐3‐(R)‐OL and 4‐(S)‐Naphthalen‐2‐Yloxy‐1‐(1‐Phenyl‐(S)‐Ethyl)‐Pyrrolidin‐3‐(S)‐OL: Versatile Chiral Intermediates for Synthesis

Daniel D. Holsworth,¹ Michael Stier,¹ Wei Wang,² Jeremy J. Edmunds,¹ Tingsheng Li,³ and Samarendra N. Maiti³

¹Department of Chemistry and Discovery Technologies,Pfizer Global Research and Development, Ann Arbor, MI, USA

²Department of Chemistry, Naeja Pharmaceutical, Inc., Edmonton, Alberta T6E 5V2, Canada

A convenient and rapid synthesis of 4‐(R)‐(naphthalen‐2‐yloxy)‐1‐(1‐phenyl‐(S)‐ethyl)‐pyrrolidin‐3‐(R)‐ol (Compound 1) and 4‐(S)‐(naphthalen‐2‐yloxy)‐1‐(1‐phenyl‐(S)‐ethyl)‐pyrrolidin‐3‐(S)‐ol (Compound 2) is disclosed. The reaction scheme is highlighted by the meso‐epoxidation of 1‐(1‐phenyl‐(S)‐ethyl)‐2,5‐dihydro‐1H‐pyrrole followed by addition of 2‐naphthol alkoxide to provide both expected diastereoisomers. Separation of the diastereoisomers by crystallization provided access to both diastereoisomers in modest yield without the employment of expensive chiral catalysts. An x‐ray structure of Compound 1 was obtained to unambiguous assign the stereochemistry. These chiral pyrrolidine analogs should be useful as intermediates in natural product, combinatorial/parallel synthesis, and medicinal chemistry.

Abstract

Synth. Commun. 2004, 34, 4431

Efficient and Convenient Method for the Synthesis of Poly Functionalised 4H‐Pyrans

B. P. V. Lingaiah, G. Venkat Reddy, T. Yakaiah, B. Narsaiah, S. N. Reddy, R. Yadla, and P. Shanthan Rao

Fluoroorganics Division, Indian Institute of Chemical Technology, Hyderabad, India