Letters in Organic Chemistry

ISSN: 1570-1786

Letters in Organic Chemistry
Volume 3, Number 8, August 2006

Highlights in Organic Chemistry

Oxidative Aromatization Using Molecular Oxygen Promoted by Activated Carbon Pp. 571-578

Masahiko Hayashi & Yuka Kawashita 2-Arylbenzoxazoles, 2-arylbenzimidazoles and 2-arylbenzothiazoles were directly synthesized from substituted 2-aminophenols and aldehydes in the presence of activated carbon (Darco KB or Shirasagi KL) in xylene under an oxygen atmosphere.

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Letters in Organic Chemistry

A Simple Facile Synthesis of Bifluorenylidenes Pp. 579-584

Amalia Levy, Michal Goldschmidt & Israel Agranat Bifluorenylidenes were synthesized in two steps, by conversion of fluorenones to fluorenethiones followed by reductive dimerization of the latter in boiling benzene.

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Investigating the Effects of Cation Electrophilicity, Solvent, and Temperature on the N-Nitrosoamide-Mediated Polymerization of Styrene Pp. 585-590

Ron W. Darbeau, Ulku Ramelow, Mark S. Delaney & Melanie Guillory N-Nitrosoamide-derived (deaminative) Carbocations as Initiators of Addition Polymerization of Styrene.

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Clean Synthesis of 14-Alkyl and 14-Aryl-14-H-dibenzo[a,j]xanthenes Pp. 591-596

Tong-Shou Jin, Li-Bin Liu, Ying Yin, Ying Zhao & Tong-Shuang Li Two clean and efficient methods for the synthesis of 14-alkyl and 14-aryl-14-H-dibenzo[a,j]xanthenes are described: (1) in aqueous media, using p-dodecylbene-zenesulfonic acid as the catalyst, under heat conditions. (2) Under solvent-free condition, using p-toluene sulfonic acid as catalyst and in microwave irradiation.

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Indium-Mediated Allylation of α,α-Dichloroketones: The Synthesis of 1,1 Dichloro-2-organyl-pent-4-en-2-ols Pp. 597-599

Clovis Peppe, José A. Nóbrega, Lia D. Drehmer & Marcos A.P. Martins The allylindium reagents obtained from metallic indium and allyl bromides, in THF, couple chemioselectively to the carbonyl group of α,α- dichloroketones to afford 1,1-dichloro-2-organyl-pent-4-en-2-ols in good to excellent yields.

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A Novel Acid-Assisted Transformation of Cyclopentadiene Endoperoxides to Pyrylium Cations Pp. 600-603

Weitao Gong, Tao Xu, Guiling Ning, Xincheng Li, Yuan Lin & Liqiu Wang

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A Highly Conjugated Polymerizable Fluorene-Based 1,3-Dithietane Pp. 604-606

Kavithaa Loganathan & Peter G. Pickup Reaction of 2,7-(2-thienyl)fluoren-9-one with Lawesson's reagent produces a low HOMO-LUMO gap 1,3-dithietane that can be electrochemically polymerised to yield a low band gap poly(fluorene-co-dithiophene) copolymer.

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Homocoupling of Terminal Alkynes to 1,4-Disubstituted 1,3-Diynes Promoted by Copper(I) Iodide and a Task Specific Ionic Liquid, [bmim]OH – A GreenProcedure Pp. 607-609

Brindaban C. Ranu & Subhash Banerjee A simple and efficient method for the oxidative homocoupling of terminal alkynes to symmetrical 1,4-disubstiuted 1,3-diynes has been developed using CuI in ionic liquid, [bmIm]OH under atmospheric condition.

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A Novel and Convenient Method for the Synthesis of Ubiquinone-10 Pp. 610-612

Feng Wang, Xiangrui Jiang, Lihong Hu, Shengyi Dong, Xiumei Wu, Hua Bai, Yongmin Zhang, Joachim Stöckigt & Yu Zhao A novel and convenient synthetic approach to ubiquinone-10 was reported via the SN2’-type nucleophilic displacement reaction between copper-catalyzed Grignard reagent and the secondary allylic acetate.

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Application of Bioreduction by Microorganisms in the Enantioselective Synthesis of Alpha-Substituted-1-Phenylethanols Pp. 613-618

Leandro H. Andrade, Roberta Polak, André L.M. Porto, Iracema H. Schoenlein-Crusius & João V. Comasseto The enantioselective bioreduction of alpha-substituted-acetophenones 1,2 was carried out with cells of fungi to give the corresponding chiral alcohols in good yield and high enantioselectivity (up to 99%).

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Reductive Cyclisation of 2-Cyanomethyl-3-Nitrobenzoates Pp. 619-621

Esther C.Y. Woon, Archana Dhami, Peter T. Sunderland, David A. Chalkley & Michael D. Threadgill Selective reduction of methyl 2-cyanomethyl-3-nitrobenzoate with DiBAL-H at low temperature, followed by cyclisation in situ gave 5-nitroisoquinolin-1-one. Steric bulk at the methylene switched reduction to the ester. The isopropyl ester gave 5-nitroisoquinoline.

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Synthesis of N-Chlorodiazinones Using Sodium Hypochlorite Solution Pp. 626-628

Osamu Sugimoto, Satomi Uchitani, Mizuki Endo & Ken-ichi Tanji N-Chlorodiazinones were newly synthesized by reaction of diazinones with sodium hypochlorite in aqueous media in excellent to good yields.

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Three Components Ring Transformation Affording Substituted 5 Nitropyridines and 4-Nitroanilines Pp. 629-633

Nagatoshi Nishiwaki, Hiroshi Tatsumichi, Mina Tamura & Masahiro Ariga The ring transformation of 1-methyl-3,5-dinitro-2-pyridone afforded 2-aryl 5-nitropyridines upon treatment with aromatic ketones in the presence of ammonium acetate. In reactions with aliphatic ketones, 2,6-disubstituted 4-nitroanilines could be prepared in addition to corresponding 2,3 disubstituted 5-nitropyridines. In these reactions, dinitropyridone behaved as the synthetic equivalent of unstable nitromalonaldehyde.

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A Practical Synthesis of Thio-Bisphosphonic Acids For the Treatment of Arthritis, Based on the Chemistry of Tetraethyl Methylene-1,1 Bisphosphonate Pp. 634-639

Wafaa Mahmoud Abdou, Maha Darwish Khidre & Ashraf Ahmed Sediek A series of novel S -bisphosphonic Acids were synthesized by application of tetraethyl methylene-1, 1-bisphosphonate on some 1,2- dithioles. The in vivo activity of produced S-BP-acids in the rat adjuvant model is also discussed.

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A Convenient and Practical Method for the Synthesis of Aromatic N-Thiophosphoryl Imines Pp. 640-642

Xinyuan Xu, Chungui Wang, Zhenghong Zhou, Zebing Zeng, Xinpeng Ma, Guofeng Zhao & Chuchi Tang Thermal condensation of acetals with different thiophosphoramides at 120-160 0C resulted in the formation of the corresponding N thiophosphoryl imines in good excellent yield (80-98%) with high purity (>95%, determined by 1H NMR and elemental analyses).

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Versatile Synthesis of MRI Contrast Agents Based on Carbon Substituted Triazacycloalkanes Pp. 643-647

Lassi Jaakkola & Jari Hovinen 3-(4-Iodophenoxy)-tris(2-nitrobenzenesulfonyl)-1,4,7-triazacyclodecane was synthesized by a Mitsunobu reaction between pernosylated diethylenetriamine and 1,3-bis(trityloxy)propan-2-ol. It served as a key intermediate in the preparation of MRI contrast agents allowing biomolecule labeling both in solution and on solid phase.

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