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Letters in Organic Chemistry
ISSN: 1570-1786
Letters in Organic Chemistry
Volume 4, Number 4, June 2007
Asymmetric Induction in Darzens Condensation by Means
of (R) 5,5-Dimethyl-4-Phenyloxazolidin-2-One as an Effective
Chiral Auxiliary Pp. 228-231
Abed Badrian, Manouchehr Mamaghani, Khalil Tabatabaeian
and Hassan Valizadeh
[Abstract]
Stereoselective Synthesis of the Core of Naturally
Occurring Anti HIV Isolitseane B
Pp. 232-233
Paul Brémond, Elodie Girardeau, Yoann Coquerel
and Jean Rodriguez
[Abstract]
Lipase Catalysed Kinetic Resolution of 2-Nitroalcohol:
Total Synthesis of Taxol Side Chain and (-)-Bestatin
Pp. 234-235
Naminita Gogoi, Jagat C. Borah, Joshodeep Boruwa and Nabin
C. Barua
[Abstract]
High-Yielding Aminocarbonylation of 3-Iodo-2-Tropene
by Using Amino Acid Esters as N-Nucleophiles
Pp. 236-238
László Horváth, Zoltán Berente
and László Kollár
[Abstract]
Synthesis of a Library of N-Substituted Methyl Aminocarbonyl
Acetates using Poly(Ethylene Glycol) as Soluble Support
Pp. 239-241
Xiaoqing Yan, Jingjun Yu, Ronghua Ye, Zuxing Chen and
Guichun Yang
[Abstract]
Ionic Liquid Functionalized SBA-15 Promoted Rapid
and Facile Aza-Michael Reaction Pp. 242-245
Chuan Wu, Li-Wen Xu, Ming-Song Yang, Jian-Xiong Jiang,Hua
Yu Qiu and Guo-Qiao Lai
[Abstract]
MgI2 Etherate-Promoted
Allylation of Aldehydes: Simple and Efficient Synthesis of
Homoallylic Alcohols Pp. 246-248
Xingxian Zhang
[Abstract]
SeO2/H2O2/H2O-Dioxane:
A New Catalytic System for Trans Dihydroxylation of Olefins
Pp. 249-252
Pranjal Gogoi, Saikat Das Sharma and Dilip Konwar
[Abstract]
Palladium Catalyzed Decarbonylative Mizoroki-Heck
Reactions of Benzoyl Chloride and Styrene Under Microwave
Irradiation Pp. 253-255
Daniela de Luna Martins, Heiddy M. Alvarez, Lúcia
C.S. Aguiar and O.A.C. Antunes
[Abstract]
A Mild and Efficient C-3 Allylic Alkylation
of Indoles Catalyzed by FeCl3
Pp. 256-260
Zhe Liu, Li Liu, Zahid Shafiq, Dong Wang and Yong-Jun
Chen
[Abstract]
From Head to Tail: Microwave-Assisted Synthesis of
Para Hydrazine Nicotinamide Phenylalanine8-Oxytocin
Derivatives Pp. 261-264
Alma D. Miranda-Olvera, Ignacio A. Rivero Espejel and
Luis M. De León Rodríguez
[Abstract]
A Facile Microwave-Assisted Synthesis of p-Quinols
by Lead(IV) Acetate Oxidation Pp. 265-267
Katalin Prokai-Tatrai, Nilka M. Rivera-Portalatin, Navin
Rauniyar and Laszlo Prokai
[Abstract]
An Unprecedented “Reverse” 1,2 Migration
of a Nitro Group within an α-Aryl-β-nitroethenyl
Moiety Driven by Steric and Stereoelectronic Effects
Pp. 268-272
Lara Bianchi, Gianluca Giorgi, Massimo Maccagno, Giovanni
Petrillo, Egon Rizzato,Domenico Spinelli, Marco Stenta and
Cinzia Tavani
[Abstract]
A Convenient Synthesis of Novel Substituted Isoxazolo[5,4-d]
Pyrimidines Pp. 273-280
Sergey B. Aliabiev, Raisa V. Bykova, Dmitri V. Kravchenko
and Alexandre V. Ivachtchenko
[Abstract]
Thia-Michael Addition Reactions in Water Using 3-[Bis(Alkylthio)
Methylene]Pentane-2,4-Diones as Odorless and Efficient Thiol
Equivalents Pp. 281-284
Yanyan Chai, Dewen Dong, Yan Ouyang, Yongjiu Liang, Yan
Wang, Minghui Li and Qun Liu
[Abstract]
An Efficient Preparation of 2-Methyl-1-Cyclopentene-1-Carboxylic
Acid, a Versatile Synthetic Building Block Pp. 285-287
Simonetta Benetti, Carmela De Risi, Francesco Ferroni
and Gian P. Pollini
[Abstract]
Synthesis of Gallocatechin-3-Gallate Analogues
Pp. 288-291
Nadia Vaiana, Luca Rizzi, Maria G. Pezzano, Roberto Restelli,
Filippo Rota, Silvia Stefanini, Silvia Vicentini and Sergio
Romeo
[Abstract]
Novel Naproxen Derivatives: Lewis Acid/Transition-metal
Free Synthesis via C-C Bond Forming Reaction
Pp. 292-295
Sarbani Pal, P. Bindu, Pragnyadhar Reddy Venna and P.K.
Dubey
[Abstract]
An Efficient and Facile Synthesis of 2-Amino-5,6,7,8-tetrahydro
4- aryllnaphthalene-1,3-dicarbonitrile and 5-Amino-2,3-dihydro-7-
aryl-1H-indene-4,6-dicarbonitrile via Multicomponent
Coupling Reaction Under Solvent-Free Conditions Pp.
296-299
Liangce Rong, Haiying Wang, Xiaoyue Li, Fang Yang, Hao,
Yao, Shujiang Tu and Daqing Shi
[Abstract]
Bacteriorhodopsin Analogue from Indolic Chromophores
Pp. 300-305
Prasanta Kumar Hota and Anil Kumar Singh
[Abstract]
Abstracts
[Back to top]
Asymmetric Induction in Darzens Condensation
by Means of (R) 5,5-Dimethyl-4-Phenyloxazolidin-2-One as an
Effective Chiral Auxiliary
Abed Badrian, Manouchehr Mamaghani, Khalil Tabatabaeian
and Hassan Valizadeh
(R)-5,5-dimethyl-4-phenyloxazolidin-2-one 1
which is readily available from (R)-phenylglycine, was shown
to be an effective chiral auxiliary for asymmetric Darzens
reaction. It was employed in a simple and practical approach
for the preparation of optically active glycidic esters.
[Back to top]
Stereoselective Synthesis of the Core of Naturally
Occurring Anti HIV Isolitseane B
Paul Brémond, Elodie Girardeau, Yoann Coquerel
and Jean Rodriguez
A key intermediate in the total synthesis of naturally occurring
anti-HIV Isolitseane B has been prepared in five steps from
propargyl alcohol, featuring a highly selective mono-transacetalization
and a stereoselective Pauson-Khand cyclization.
[Back to top]
Lipase Catalysed Kinetic Resolution of 2-Nitroalcohol:
Total Synthesis of Taxol Side Chain and (-)-Bestatin
Naminita Gogoi, Jagat C. Borah, Joshodeep Boruwa and Nabin
C. Barua
2-Nitroalcohols were efficiently resolved by Lipase catalysed
transesterification process. This protocol was successfully
applied to the synthesis of taxol side chain and (-)-bestatin
in overall yields of 40% and 20% respectively.
[Back to top]
High-Yielding Aminocarbonylation of 3-Iodo-2-Tropene
by Using Amino Acid Esters as N-Nucleophiles
László Horváth, Zoltán Berente
and László Kollár
3-Iodo-2-tropene, synthesised from the corresponding ketone
(tropinone) via its hydrazone, was carbonylated in
palladium-catalysed homogeneous aminocarbonylation reactions.
The 3-carboxamides containing both the tropene and the aminoacid
moieties of biological importance were obtained in chemospecific
reactions and isolated in up to 85 % yields.
[Back to top]
Synthesis of a Library of N-Substituted Methyl Aminocarbonyl
Acetates using Poly(Ethylene Glycol) as Soluble Support
Xiaoqing Yan, Jingjun Yu, Ronghua Ye, Zuxing Chen and
Guichun Yang
A rapid and solvent-free synthesis of methyl 2-(N-substituted
aminocarbonyl) acetates has been developed using poly (ethylene
glycol) (PEG) as a soluble polymeric support and as a protecting
group. PEG was first reacted with Meldrum’s acid to
give PEG-bound malonic acid 2 under microwave-irradiation,
and then 2 was coupled with series of amines
to produce 3, followed by the cleavage from
the PEG using KCN in CH3OH
to afford N-substituted methyl aminocarbonyl acetates 4.
This simple method requires mild reaction conditions and affords
moderate to high yields of the desired products with excellent
purities.
[Back to top]
Ionic Liquid Functionalized SBA-15 Promoted Rapid
and Facile Aza-Michael Reaction
Chuan Wu, Li-Wen Xu, Ming-Song Yang, Jian-Xiong Jiang,Hua
Yu Qiu and Guo-Qiao Lai
The ionic liquids functionalized mesoporous materials were
prepared and they exhibited high and dramatic catalytic activity
in the aza-Michael addition of amines and NH-containing heterocycles
to α,β-unsaturated
carbonyl compounds. Recycling of the catalyst in these reactions
was carried out and the catalyst could be used at least five
times without significant loss in activity.
[Back to top]
MgI2 Etherate-Promoted
Allylation of Aldehydes: Simple and Efficient Synthesis of
Homoallylic Alcohols
Xingxian Zhang
We describe a mild and efficient procedure for the synthesis
of homoallylic alcohols using allyltributylstannane in the
presence of MgI2 etherate
(MgI2•(OEt2)n)
in good to excellent yields.
[Back to top]
SeO2/H2O2/H2O-Dioxane:
A New Catalytic System for Trans Dihydroxylation of Olefins
Pranjal Gogoi, Saikat Das Sharma and Dilip Konwar
A novel selenium dioxide catalyzed dihydroxylation of various
olefins using hydrogen peroxide as stoichiometric oxidant
is reported. Also, the reagent system cleaves activated carbon-carbon
double bonds to their corresponding carbonyls.
[Back to top]
Palladium Catalyzed Decarbonylative Mizoroki-Heck
Reactions of Benzoyl Chloride and Styrene Under Microwave
Irradiation
Daniela de Luna Martins, Heiddy M. Alvarez, Lúcia
C.S. Aguiar and O.A.C. Antunes
A decarbonylative MH-type procedure is described using polar
solvents under microwave irradiation in the presence of different
palladium catalysts. Moderate to good yields were achieved
employing 1,4-diazabicycle[2.2.2]octane as base in 10 min
of reaction.
[Back to top]
A Mild and Efficient C-3 Allylic Alkylation
of Indoles Catalyzed by FeCl3
Zhe Liu, Li Liu, Zahid Shafiq, Dong Wang and Yong-Jun
Chen
A mild and efficient allylic alkylation of indole derivatives
has been developed with high regioselectivity and excellent
yields. In the presence of 1mol% FeCl3
catalyst, various indole derivatives could react with allylic
acetates at room temperature to provide C-3 allylation
products. A green synthesis of C-3 allylated indoles
was developed employing FeCl3
as catalyst in water.
[Back to top]
From Head to Tail: Microwave-Assisted Synthesis of
Para Hydrazine Nicotinamide Phenylalanine8-Oxytocin
Derivatives
Alma D. Miranda-Olvera, Ignacio A. Rivero Espejel and
Luis M. De León Rodríguez
Currently, the generation of peptide ligand libraries where
ligand position and identity are varied leading to the discovery
of optimal peptide activity and stability is limited. Thus,
in this work the synthesis of a p-Dde-Na-Fmoc-phenylalanine
residue is reported followed by its application in the microwave
assisted synthesis of labeled HYNIC Phe8-oxitocine
derivatives.
[Back to top]
A Facile Microwave-Assisted Synthesis of p-Quinols
by Lead(IV) Acetate Oxidation
Katalin Prokai-Tatrai, Nilka M. Rivera-Portalatin, Navin
Rauniyar and Laszlo Prokai
A rapid, convenient and reliable procedure to obtain a variety
of p-quinols via microwave-assisted oxidation
of the corresponding p-alkylphenols was developed.
Unlike the conventional methods that require several hours,
our approach provides the target compounds within 30 min.
[Back to top]
An Unprecedented “Reverse” 1,2 Migration
of a Nitro Group within an α-Aryl-β-nitroethenyl
Moiety Driven by Steric and Stereoelectronic Effects
Lara Bianchi, Gianluca Giorgi, Massimo Maccagno, Giovanni
Petrillo, Egon Rizzato,Domenico Spinelli, Marco Stenta and
Cinzia Tavani
The release of repulsive interactions of steric and/or stereoelectronic
nature and the onset of a new extended and effective conjugation
concur to an unprecedented and synthetically appealing shift
of a nitro group from the β-
to the α-position
with respect to the aryl group of a styrene moiety.
[Back to top]
A Convenient Synthesis of Novel Substituted Isoxazolo[5,4-d]
Pyrimidines
Sergey B. Aliabiev, Raisa V. Bykova, Dmitri V. Kravchenko
and Alexandre V. Ivachtchenko
In this work, we present a convenient synthetic route to novel
substituted derivatives of isoxazolo[5,4-d]pyrimidines.
Starting from 5-amino-isoxazole-4-carboxamides, we have obtained
a series of 3,6-substituted isoxazolo[5,4-d]pyrimidin-4(5H)-ones
via intermolecular cyclization of initial heterocycles
with ethyl triethoxyacetate or diethyl oxalate/succinate.
We have also synthesized a number of 4-amino substituted isoxazolo[5,4-d]pyrimidines
and 4-amino-isoxazolo[5,4-d]pyrimidine-6-carboxamides
using a convenient and simple synthetic approach. We demonstrate
the usefulness and versatility of the developed strategy,
which can be easily adapted to high-throughput combinatorial
format, for the synthesis of variously substituted compounds
containing this core fragment.
[Back to top]
Thia-Michael Addition Reactions in Water Using 3-[Bis(Alkylthio)
Methylene]Pentane-2,4-Diones as Odorless and Efficient Thiol
Equivalents
Yanyan Chai, Dewen Dong, Yan Ouyang, Yongjiu Liang, Yan
Wang, Minghui Li and Qun Liu
3-[Bis(ethylthio)methylene]pentane-2,4-dione (1a)
and 3-[bis(benzylthio)methylene]pentane-2,4-dione (1b)
have been investigated as non-thiolic and odorless thiol equivalents
in thia-Michael addition reactions. In the presence of aqueous
p-dodecyl benzenesulfonic acid (DBSA), compound (1)
was cleaved and the generated thiols underwent facile conjugate
addition to α,β-unsaturated
ketones 2 in-situ, affording the corresponding
β-keto
sulfides (3) in good yields.
[Back to top]
An Efficient Preparation of 2-Methyl-1-Cyclopentene-1-Carboxylic
Acid, a Versatile Synthetic Building Block
Simonetta Benetti, Carmela De Risi, Francesco Ferroni
and Gian P. Pollini
A practical three-step procedure for the preparation of 2-methyl-1-cyclopentene-1-carboxylic
acid is detailed. This process relies on the reaction of commercially
available 2-carboethoxycyclopentanone with nitromethane in
the presence of equimolecular amounts of piperidine, followed
by denitration of the derived allylic nitro compound by treatment
with 5% Pd/C in the presence of ammonium formate and final
hydrolysis of the ester moiety.
[Back to top]
Synthesis of Gallocatechin-3-Gallate Analogues
Nadia Vaiana, Luca Rizzi, Maria G. Pezzano, Roberto Restelli,
Filippo Rota, Silvia Stefanini, Silvia Vicentini and Sergio
Romeo
The influence of substituents on the yields of the synthesis
of seven catechines analogues has been studied. 3-Flavene
formation is favoured by electron donors substituents on the
A and B rings. Yields of the hydroboration reaction are increased
by electron donor substituents on the A ring, while substituents
on the B ring do not affect the reaction outcome.
[Back to top]
Novel Naproxen Derivatives: Lewis Acid/Transition-metal
Free Synthesis via C-C Bond Forming Reaction
Sarbani Pal, P. Bindu, Pragnyadhar Reddy Venna and P.K.
Dubey
Naproxen or 2-(6-methoxy naphthalen-2-yl)propionic acid participated
in trifluoroacetic anhydride/ phosphoric acid mediated C-C
bond forming reaction in a regioselective fashion when treated
with a variety of arene or heteroarene under a solvent-free
condition affording novel 1-aryl/heteroaryl substituted 2-(6-methoxy
naphthalen-2-yl)propan-1-ones in good yields.
[Back to top]
An Efficient and Facile Synthesis of 2-Amino-5,6,7,8-tetrahydro
4- aryllnaphthalene-1,3-dicarbonitrile and 5-Amino-2,3-dihydro-7-
aryl-1H-indene-4,6-dicarbonitrile via Multicomponent
Coupling Reaction Under Solvent-Free Conditions
Liangce Rong, Haiying Wang, Xiaoyue Li, Fang Yang, Hao,
Yao, Shujiang Tu and Daqing Shi
An efficient and facile synthesis of 2-amino-5,6,7,8-tetrahydro-4-arylnaphthalene-1,3-dicarbonitrile
and 5-amino-2,3-dihydro-7-aryl-1H-indene-4,6-dicarbonitrile
via three-component reaction of cyclohexanone or
cyclopentanone, aldehydes and malononitrile under solvent-free
conditions using grinding method has been developed. The mild
reaction conditions, simple protocol, good yields and cleaner
reaction make this protocol practical and economically attractive.
[Back to top]
Bacteriorhodopsin Analogue from Indolic Chromophores
Prasanta Kumar Hota and Anil Kumar Singh
A new analogue of bacteriorhodopsin (bR) was prepared by allowing
bacterioopsin (bOP), the apo-protein of bR to interact with
(2Z,4E)-3-chloro-5-(1H-indol-3-yl)-2,4-pentadienal
as chromophore. It was characterised for its opsin shift,
stability, light-induced pH change and fluorescence emission.
Indolic aldehydes viz. 1H-indole-3-carboxaldehyde
and (2Z,4E)-3-chloro-5-[1-(phenylsulfonyl)-1H-indol-3-yl]-2,4-pentadienal
did not bind bOP.
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