Letters in Organic Chemistry

ISSN: 1570-1786

Letters in Organic Chemistry
Volume 3, Number 1, January 2005

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Exploitation of Acetylenic Coupling Reactions in the Synthesis of Extended Tetrathiafulvalenes Pp. 3-9

Mogens Brøndsted Nielsen Acetylenic scaffolding with acetylenic dithiafulvenes has provided a large selection extended tetrathiafulvalenes (TTFs).

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Complete 1,3-Asymmetric Induction into 3-Methyl-4-(3-Acetylpyrrol-1-yl)Butanal to 1-Acetyl-6-Methyl-8-Hydroxy-5,6,7,8-Tetrahydroindolizine Cyclization Pp. 10-12

Roberta Settambolo, Silvia Rocchiccioli, Raffaello Lazzaroni & Giuliano Alagona The formation of 1-acetyl-6-methyl-8-hydroxy-5,6,7,8-tetrahydroindolizine (3) from 3-methyl-4-(3-acetylpyrrol-1-yl)butanal (2), coming from the rhodium catalyzed hydroformylation of 2-methyl-3-(3-acetylpyrrol-1-yl)prop-1-ene (1), is reported. Evidences for both the complete diastereoselective cyclization of 2 and configuration determination in 3 via 1H, 13C and IR spectra are reported.

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Efficient and Selective Cleavage of Silyl Ethers with Antimony Trichloride Pp. 13-15

Qinpei Wu, Yuan Wang, Wei Chen, Hao Wang & Hua Liu A convenient and efficient method for chemo- and regio-selective cleavage of silyl ethers mediated by SbCl3 at room temperature was described and the proposed mechanism was demonstrated.

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Efficient Microwave and Phosphane-Free Synthesis of Trisubstituted Olefins via Heck Coupling Pp. 16-20

Simona Collina, Mariangela Urbano, Andrea Magnani, Guya Loddo & Ornella Azzolina An easy and convenient procedure for palladium-catalyzed phosphane-free Heck arylation of disubstituted olefins via microwave irradiation is described.

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Pyrrole-Based Partial Peptidic Mimic of Neurotensin (8-13): Design and Synthesis Pp. 21-24

Javid H. Zaidi, Fazal Naeem, Nida Ambreen, Khalid M. Khan, Yuan-Ping Pang, Bernadette Cusack, Elliot Richelson, Awais Anwar & Wolfgang Voelter The synthesis of pyrrole-based semipeptidic mimic of neuropeptide neurotensin (8-13) [NT(8-13)] is described. The design of this NT mimic is based on substitution of indole by a pyrrole nucleus.

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Facile and Selective Preparation of Esters from Carboxylic Acids Catalyzed by Aluminumdodecatangstophosphate (AlPW12O40) as a Versatile, Recyclable and a Highly Water Tolerant Green Lewis Acid Catalyst Pp. 25-28

Habib Firouzabadi, Nasser Iranpoor & Abbas Ali Jafari Aluminumdodecatangstophosphate (AlPW12O40) as a highly water tolerant, recyclable green Lewis acid has been applied as an efficient catalyst for the synthesis of esters from long chain aliphatic and aromatic acids and alcohols in high yields. This catalyst is also selective for the esterification of primary alcohols in the presence of secondary ones.

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Preparation of Diarylamines and Arylhydrazines Using Palladium Catalysts Pp. 29-34

Youssef Harrak, Manel Romero, Pere Constans & Maria D. Pujol Aryl halides and aryl triflates are coupled with N-compounds to give the corresponding arylamines or arylhydrazines in the presence of a palladium catalyst, BINAP or Ph3P and Cs2CO3.

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A Facile Route for the Regioselective Deacetylation of Peracetylated Carbohydrates at Anomeric Position Pp. 35-38

Srinivas Chittaboina, Blake Hodges & Qian Wang The regioselective 1-O-deacetylation of peracetylated carbohydrates with ammonium acetate is described, which offers a facile and efficient way to prepare O-acetylpyranosides presenting one free hydroxyl group at the anomeric position.

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One-Step Reduction of Chalcones to Saturated Alcohols by Ammonium Formate/Palladium on Carbon: A Versatile Method Pp. 39-41

Carlos Kleber Z. Andrade & Wender A. Silva Several chalcones are reduced directly to the corresponding saturated alcohols, in a catalytic transfer hydrogenation process, by use of the ammonium formate/palladium on carbon system in very good yields

Diastereoisomeric Synthesis of Novel Analogues of d4T having an Isochroman Glycon Moiety Pp. 42-44

Christophe Len 1,2-O-Isopropylidene-α-D-xylofuranose has been used as a chiral protecting group of the formyl group of 2-bromobenzaldehyde, in which it acts as a resolving agent leading to separable diastereoisomers when a new stereocenter is created by substitution of bromine by a 2,3-dihydroxypropyl chain. These separated diastereoisomers were cyclised to furnish the target nucleoside analogues of d4T as an isochroman.

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A Convenient Preparation of Enantiomerically Pure Esters of trans-Epoxysuccinic Acid Pp. 45-47

Demetris P. Papahatjis, Therapia Kourouli & Victoria R. Nahmias We report herein a new and efficient four-step method for the stereoselective conversion of (-) diethyl (D)- and (+) diethyl (L)-tartrate into diethyl (2S,3S)-(+)-2,3-epoxysuccinate and diethyl (2R,3R)-(-)-2,3-epoxysuccinate respectively.

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An Asymmetric Synthesis of the γ-Amino-β-hydroxy Acid Segment of Hapalosin Pp. 54-55

Soumyaditya Mula & Subrata Chattopadhyay An efficient asymmetric synthesis of the title hapalosin segment has been developed starting from (R)-cyclohexylideneglyceraldehyde.

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A Rapid and Highly Efficient One-Pot Methodology for Preparation of Alkyl Oxindolideneacetates Pp. 56-57

Javad Azizian, Mohammad Reza Mohammadizadeh, Zahra Kazemizadeh, Narges Karimi, Ali Asghar Mohammadi, Ali R. Karimi & Abdollah Alizadeh A one-pot solvent free Wittig procedure was suggested for fast and high efficient preparation of Alkyl Oxindolideneacetates using isatin derivatives, triphenylphosphine, alkyl bromoacetate and morpholine.

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Circular Dichroism in a Chiral Amide Possessing an Achiral Binaphthyl Chromophore Pp. 58-61

Shinzo Hosoi, Jun Serata, Akiyo Sakushima, Fumiyuki Kiuchi, Ichiro Takahashi & Tomihisa Ohta Induced circular dichroism (ICD) was observed in binaphthyl amides of chiral primary amines. The CDs changed to split curves centered at 225 nm after N-methylation. The calculated screw senses of the two naphthyl groups accorded with those expected from their exciton chiralities, indicating a possible application for determination of absolute configuration.

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Prolinates as Secondary Amines in Aminocarbonylation: Synthesis of N-Acylated Prolinates Pp. 62-67

Eszter Takács, Rita Skoda-Földes, Péter Ács, Ernõ Müller, George Kokotos & László Kollár Proline esters as secondary amines have been used as nucleophiles in palladium catalysed aminocarbonylation of iodo-aromatics and iodo-alkenes both in conventional organic solvents and in [bmim][PF6] ionic liquid.

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Utilization of a Tandem Michael-Dieckmann Reaction to Synthesize Orixalone A Pp. 68-72

Gregory D. Cuny, Kyungae Lee & Sungwoon Choi A tandem Michael-Dieckmann reaction for the construction of 4-hydroxy-2-quinolinones was utilized as a key step in the synthesis of the natural product orixalone A.

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Mild Procedure for Preparing Vinyldiazoacetic Acid Esters of Carbohydrate Acetonides Pp. 73-77

Renata de Souza Rianelli, Fernando de Carvalho da Silva, Maria Cecília Bastos Vieira de Souza & Vitor Francisco Ferreira New vinyldiazoacetic acid esters of carbohydrate acetonides have been prepared in good to moderate yields. The key step of this procedure is the elimination reaction performed with α-diazo-β-hydroxy esters by using trifluoroacetic anhydride and triethylamine as reagents.

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