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Letters in Organic Chemistry
ISSN: 1570-1786
Letters in Organic Chemistry
Volume 6, Number 1, January 2009
Contents
Synthesis of Phosphorus, Arsenic and Antimony Ylides Containing
the 1,3-Dimethyl-2,4,6(1H,3H,5H)-pyrimidinetrione
Fragments Pp. 1-3
Kamal Sweidan, Ahmed Al-Sheikh, Bassam
Sweileh, Mahmoud Sunjuk and Norbert Kuhn
[Abstract] [Purchase
Article]
The Stereoselective Total Synthesis of (1S,1´R,5´R,7´R)-1-hydroxy-exo-
Brevicomin by a Chiron Approach Pp. 4-7
Jhillu S. Yadav, Kodepelly Sanjeeva Rao
and Basi V. Subba Reddy
[Abstract] [Purchase
Article]
An Efficient Synthesis of Raloxifene in Ionic
Liquid: A Green Approach Pp. 8-10
Pravin S. Shinde, Sandip S. Shinde, Atul
S. Renge, Gajanan H. Patil, Ambadas B. Rode and Rajendra
R. Pawar
[Abstract] [Purchase
Article]
Unexpected Course of Kabachnik-Fields
Reaction in the Microwave Synthesis of Quinoline-Based α-Aminophosphonates
Pp. 11-16
Marina Juribašic, Laura Stella, Željko
Marinic, Marijana Vinkovic, Pietro Traldi and Ljerka
Tušek-Božic
[Abstract] [Purchase
Article]
Three Component Mannich Reaction and
1,5-Benzodiazepine Synthesis Catalyzed by a Tetranitrile-Silver
Complex Pp. 17-21
Gopalakrishnapanicker R. Krishnan, Radhakrishnan
Sreerekha and Krishnapillai Sreekumar
[Abstract] [Purchase
Article]
Novel Stereoselective Synthesis of (R)-3-Aminotetradecanoic
Acid (Iturinic Acid) Pp. 22-24
Andrea Temperini, Marcello Tiecco, Lorenzo
Testaferri and Raffaella Terlizzi
[Abstract] [Purchase
Article]
Copper Catalyzed Coupling of α-Bromocarboxylate
with ω-Lactam
Pp. 25-28
Katerina Brychtova, Oldrich Farsa and
Jozef Csollei
[Abstract] [Purchase
Article]
Design and Synthesis of Novel N'-tert-butyl-N'
substitutedbenzoyl N[dihydrobenzofuran(chroman)]carbohydrazide
Derivatives as Potential Insect Growth Regulators Pp.
29-36
Zhiqiang Huang, Qiqi Zhao, Runqiu Huang
and Qingmin Wang
[Abstract] [Purchase
Article]
Inclusion Complexes of 2-Chloroethylnitrososulfamides
(CENS) in Natural and Modified β–Cyclodextrins
Pp. 37-40
Nabila Dhaoui, Maamoun Fatfat, Mohamed Abdaoui
and Véronique Barragan-Montero
[Abstract] [Purchase
Article]
Photochemical Studies on Benzonorbornene
Derivatives: Medium Effects and Asymmetric Induction Pp.
41-43
Chao Yang, Wujiong Xia, Qian Chen, Xiao
Zhang, Bing Li and Baoquan Gou
[Abstract] [Purchase
Article]
Asymmetric Conjugate Addition of Unmodified
Propionaldehyde to β-Nitrostyrenes
Catalyzed by Readily Available Proline-Based Dipeptidols
Pp. 44-49
Ren-Yong Yang, Chao-Shan Da, Lei Yi, Feng-Chun
Wu and Hong Li
[Abstract] [Purchase
Article]
Improved Condensation of 2-pyridyllithium
Intermediates with Aldehydes: Application for the Synthesis
of 2-(polyhydroxyalkyl) pyridines Pp. 50-56
Corinne Comoy, Julien Pétrignet,
Estelle Banaszak, Anthony Chartoire and Yves Fort
[Abstract] [Purchase
Article]
Preparation of 1,2-bis(pyrazol-1-yl)benzene:
“Modern” Cross-Coupling vs. the “Classic”
Nucleophilic Substitution Approach Pp. 57-59
Olga Ivashchuk and Vladimir I. Sorokin
[Abstract] [Purchase
Article]
Electron-Deficient Phosphines Accelerate the Heck Reaction
of Electron-rich Olefins in Ionic Liquid Pp.
60-64
Shifang Liu, Ourida Saidi, Neil Berry, Jiwu
Ruan, Alan Pettman, Nick Thomson and Jianliang Xiao
[Abstract] [Purchase
Article]
Rapid Synthesis of Taxifolione and Taxifolial
D, Two Metabolites from the Marine Alga Caulerpa taxifolia
Pp. 65-70
Fabien Fécourt, Cédric Carlier
and Patrick Pale
[Abstract] [Purchase
Article]
New Indocyanine Derivatives for the Synthesis
of Fluorescently Labeled Oligonucleotides Pp.
71-76
Edward N. Timofeev, Victoria E. Kuznetsova,
Alexander S. Zasedatelev and Alexander V. Chudinov
[Abstract] [Purchase
Article]
Efficient Heterogeneously Palladium-Catalysed
Synthesis of Stilbenes and Bibenzyls Pp.
77-81
Giuseppe Cusati, Anja Wedig and
Laurent Djakovitch
[Abstract] [Purchase
Article]
A Short Route to [1,2,3]-Triazolyl Coumarin
and Quinolone Derivatives by Cu(I) Catalyzed 1,3-Dipolar Cycloaddition
and Fluorescence Studies Pp. 82-87
Krishna C. Majumdar and Shovan
Mondal
[Abstract] [Purchase
Article]
A Short and Efficient Synthesis of the
Selective H4 Receptor Agonist
4-Methylhistamine Pp. 88-89
Mirko Rivara, Valentina Zuliani, Pier V.
Plazzi and Fabrizio Bordi
[Abstract] [Purchase
Article]
New Solid-Phase Approach to Synthesize
a Hyacinthacine Core Using the L-Proline as a Building
Block Pp. 90-93
Mônica O. Duarte, Guilherme Stedele,
Mariane Pazinatto, Eduardo R. de Oliveira and Vera
L. Eifler-Lima
[Abstract] [Purchase
Article]
Zirconium Tetrakis(dodecylsulfate) as
an Efficient and Recyclable Lewis Acid-Surfactant-Combined
Catalyzed C-C and C-N Bond Forming Under Mild and Environmentally
Benign Conditions Pp. 94-99
Maasoumeh Jafarpour, Abdolreza Rezaeifard
and Marzieh Aliabadi
[Abstract] [Purchase
Article]
Facile Regioselective Green Synthesis of Triazolo
[4,3-a] Pyrimidines in Aqueous Medium Pp.
100-105
Anshu Dandia, Ruby Singh, Dharmendra Singh
and Kapil Arya
[Abstract] [Purchase
Article]
Abstracts
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Article]
Synthesis of Phosphorus, Arsenic and Antimony Ylides Containing
the 1,3-Dimethyl-2,4,6(1H,3H,5H)-pyrimidinetrione
Fragments
Kamal Sweidan, Ahmed Al-Sheikh, Bassam
Sweileh, Mahmoud Sunjuk and Norbert Kuhn
The ylides Ph3E-C6H6N2O3
(7, E = P (a), As (b),
Sb (c)) have been prepared through the reaction
of Ph3E and 5-bromo-1,3-dimethyl-2,4,6(1H,3H,5H)-pyrimidinetrione
(5-bromo-1,3-dimethylbarbituric acid) 6 in
the presence of triethylamine. Their characterisation was
performed by nuclear magnetic resonance (NMR), mass spectrometry
(MS) and elemental analysis.
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Article]
The Stereoselective Total Synthesis of (1S,1´R,5´R,7´R)-1-hydroxy-exo-
Brevicomin by a Chiron Approach
Jhillu S. Yadav, Kodepelly Sanjeeva Rao
and Basi V. Subba Reddy
(1S,1´R´5´R,7´R)-1-Hydroxy-exo-brevicomin
has been synthesized in a highly efficient manner using D-glucono-d-lactone
as a chiral precursor. The synthesis involves the Grignard
cross coupling, Wacker oxidation and intramolecular acetalization
as the key steps.
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Article]
An Efficient Synthesis of Raloxifene in Ionic Liquid:
A Green Approach
Pravin S. Shinde, Sandip S. Shinde, Atul
S. Renge, Gajanan H. Patil, Ambadas B. Rode and Rajendra
R. Pawar
An efficient and green procedure for the synthesis of
raloxifene has been developed by using Suzuki couplings, Friedel-Crafts
acylation, and copper catalyzed coupling reactions in an ionic
liquid.
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Article]
Unexpected Course of Kabachnik-Fields Reaction in the Microwave
Synthesis of Quinoline-Based α-Aminophosphonates
Marina Juribašic, Laura Stella, Željko
Marinic, Marijana Vinkovic, Pietro Traldi and Ljerka
Tušek-Božic
The course of Kabachnik-Fields reaction in the synthesis
of 3-substituted quinoline-based α-amino-phosphonates
under microwave irradiation has been investigated. Some unexpected
monoester hydrogen phosphonate derivatives, obtained along
with diethyl phosphonates by reaction of quinoline-3-carboxaldehyde
and aniline as well as 3-aminoquinoline and benzaldehyde,
respectively, with diethyl phosphite, have been analyzed and
discussed.
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Article]
Three Component Mannich Reaction and 1,5-Benzodiazepine Synthesis
Catalyzed by a Tetranitrile-Silver Complex
Gopalakrishnapanicker R. Krishnan, Radhakrishnan
Sreerekha and Krishnapillai Sreekumar
This manuscript describes the first example of silver
ion complex of a dendritic tetranitrile ligand catalyzed one-pot
three component Mannich reaction and 1,5-benzodiazepine synthesis.
The catalyst can be separated from the products by a change
in the solvent. The catalyst is reusable.
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Article]
Novel Stereoselective Synthesis of (R)-3-Aminotetradecanoic
Acid (Iturinic Acid)
Andrea Temperini, Marcello Tiecco, Lorenzo
Testaferri and Raffaella Terlizzi
(R)-3-Aminotetradecanoic acid (iturinic acid)
has been synthesized starting from dodecanoyl chloride. This
new synthetic approach involved the enantioselective reduction
of an ynone to the corresponding propargylic alcohol and then
into a protected propargylic amine. The iturinic acid was
obtained by the transformation of a (phenylseleno)acetylene
intermediate into a carboxylic group followed by N-deprotection.
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Article]
Copper Catalyzed Coupling of α-Bromocarboxylate
with ω-Lactam
Katerina Brychtova, Oldrich Farsa and
Jozef Csollei
This paper especially deals with the problem associated
with the reaction of a-bromocarboxyl compound and 5-membered
ω-lactam
ring. Specific heterogeneous copper catalyst was used to achieve
the C-N nucleophilic coupling. Synthetic pathway of ethyl-6-(2,5-dioxopyrrolidin-1-yl)-2-(2-oxopyrrolidin-1-yl)hexanoate
as the key intermediate of new potential transdermal enhancers
is described. All generated compounds were characterized by
NMR and IR spectroscopy.
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Article]
Design and Synthesis of Novel N'-tert-butyl-N' substitutedbenzoyl-N-
[dihydrobenzofuran(chroman)]carbohydrazide Derivatives as
Potential Insect Growth Regulators
Zhiqiang Huang, Qiqi Zhao, Runqiu Huang
and Qingmin Wang
Six of new N'-tert-butyl-N'-substitutedbenzoyl-N-(2,4-dimethyl-2,3-dihydrobenzofuran)-7-carbohydrazide
derivatives and five of new N'-tert-butyl-N'-substitutedbenzoyl-N-(5-methylchroman)-8-carbohydrazide
derivatives were designed and synthesized from m-cresol. The
synthesis highlighted that some kinds of reactions were ameliorated
in methodology. An important feature is that 1-(3-allyl-2-hydroxy-4-methylphenyl)ethanone
can easily be transformed into 1-(2,3-dihydro-2,4-dimethylbenzofuran-7-yl)ethanone
just with concentrated sulfuric acid as catalyst. In addition,
we found that 1-(5-methyl-2H-chromen-8-yl)ethanone could not
be reduced to 1-(5-methylchroman-8-yl)ethanone directly by
hydrogen with Pd/C as catalyst. It is an effective method
for protecting 1-(5-methyl-2H-chromen-8-yl)ethanone with ethylene
glycol to obtain 5-methyl-8-(2-methyl-1,3-dioxolan-2-yl)-2H-chromene
and then reducing by hydrogen with Pd/C as catalyst to produce
1-(5-methylchroman-8-yl)ethanone in one step. Furthermore,
SOCl2 can convert 2,3-dihydro-2,4-dimethylbenzofuran-7-carboxylic
acid to 2,3-dihydro-2,4-dimethylbenzofuran-7-carbonyl chloride,
but it is inefficient for transforming 5-methylchroman-8-carboxylic
acid to the corresponding acyl chloride. Hence, different
heterocycles on the benzene ring of benzoheterocyle moiety
have influence on the reaction property of the corresponding
acid.
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Inclusion Complexes of 2-Chloroethylnitrososulfamides (CENS)
in Natural and Modified β–
Cyclodextrins
Nabila Dhaoui, Maamoun Fatfat, Mohamed Abdaoui
and Véronique Barragan-Montero
A series of nine inclusion complexes have been prepared
in the solid state between three different 2-chloroethylnitrososulfamides
(CENS) and three different cyclodextrins (β-cyclodextrin,
methyl-β-cyclodextrin
and (2-hydroxylpropyl)-β-cyclodextrin).
The formation of inclusion complexes with a 1/1 stoichiometry
has been confirmed. NMR studies showed that the CENS moiety
is encapsulated in CDs cavities in a tilted equatorial orientation.
Since biological evaluation showed that the cyclodextrins
have only a slight effect on the activity of the drugs toward
two cancer cell lines, the possibility exists that the complexes
may find pharmaceutical use by improving the drugs’
in vivo bioavailability and stability.
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Photochemical Studies on Benzonorbornene Derivatives: Medium
Effects and Asymmetric Induction
Chao Yang, Wujiong Xia, Qian Chen, Xiao
Zhang, Bing Li and Baoquan Gou
The photochemical behaviors of benzonorbornene derivatives
were investigated in the solid state as well as in the solution.
In acetonitrile solution, benzonorbornene derivatives underwent
the Norrish type II reaction affording a ratio of 1:1 of cyclization
and cleavage products, whereas in the solid state, the sole
cyclization product was obtained. The stereochemistry of the
photoproducts was identified by the X-ray crystallography.
Enantiomeric excesses of up to 97% can be achieved through
the use of the solid-state ionic chiral auxiliary method of
asymmetric synthesis.
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Article]
Asymmetric Conjugate Addition of Unmodified Propionaldehyde
to β-Nitrostyrenes
Catalyzed by Readily Available Proline-Based Dipeptidols
Ren-Yong Yang, Chao-Shan Da, Lei Yi, Feng-Chun
Wu and Hong Li
Organocatalytic asymmetric additions of unmodified aldehydes
to β-nitrostyrenes
are important carbon-carbon bond formation reactions and have
become very attractive recently, because they are metal-free
and environmentally benign. This work employed a series of
L-proline-based diphenyl dipeptidols to catalyze
this reaction. The results showed that these dipeptidols were
effective organocatalysts with the yield up to 99%. 3a
was optimal with the highest enantioselectivity up to 75%
and dr (syn/anti) up to 94/6. In addition, the mechanism
of this asymmetric reaction is also discussed.
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Improved Condensation of 2-pyridyllithium Intermediates with
Aldehydes: Application for the Synthesis of 2-(polyhydroxyalkyl)
pyridines
Corinne Comoy, Julien Pétrignet,
Estelle Banaszak, Anthony Chartoire and Yves Fort
The scope and the limitations of 3-chloro-2-pyridinyl
lithium condensation to aldehydes were envisioned depending
on metallation conditions or condensation time and temperatures.
The procedure was applied to various aromatic, aliphatic or
functionalized aldehydes to afford a new and efficient access
to 2-(polyhydroxyalkyl)pyridines.
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Article]
Preparation of 1,2-bis(pyrazol-1-yl)benzene: “Modern”
Cross-Coupling vs. the “Classic” Nucleophilic
Substitution Approach
Olga Ivashchuk and Vladimir I. Sorokin
Several potential methods for the preparation of 1,2-bis(pyrazol-1-yl)benzene,
a prospective ligand for transitional metals, starting from
1,2-dihalobenzenes and pyrazole have been studied. Cross-couplings
of 1,2-dichloro-, -dibromo- and -diiodobenzenes with pyrazole
using palladium and copper catalysts were unsatisfactory because
of dehalogenation side reactions or a lack of reactivity.
On the other hand, nucleophilic aromatic substitution of fluorine
in 1,2-difluorobenzene under the action of sodium pyrazolide
gave a good yield of the desired product.
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Electron-Deficient Phosphines Accelerate the Heck Reaction
of Electron-rich Olefins in Ionic Liquid
Shifang Liu, Ourida Saidi, Neil Berry, Jiwu
Ruan, Alan Pettman, Nick Thomson and Jianliang Xiao
Using various substrates and ligands, we show that electron-deficient,
bidentate phosphines are the ligands of choice for palladium-catalyzed
arylation of electron-rich olefins. This is in contrast to
the reaction of electron-deficient olefins, which benefit
from electron-rich monodentate phosphines. A tentative explanation
is offered based on DFT calculations.
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Rapid Synthesis of Taxifolione and Taxifolial D, Two Metabolites
from the Marine Alga Caulerpa taxifolia
Fabien Fécourt, Cédric Carlier
and Patrick Pale
The synthesis of two natural products - Taxifolione and
Taxifolial D – isolated from the marine alga Caulerpa
taxifolia invading the Mediterranean Sea was performed.
Coupling reactions allowed for a rapid synthesis. The surprising
Z configuration of Taxifolial D was confirmed after synthesis
and comparison of each synthetic stereoisomer.
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New Indocyanine Derivatives for the Synthesis of Fluorescently
Labeled Oligonucleotides
Edward N. Timofeev, Victoria E. Kuznetsova,
Alexander S. Zasedatelev and Alexander V. Chudinov
New sulfonated Cy3 and Cy5 phosphoramidites and solid
supports were synthesized. These building blocks were used
in the synthesis of terminally or internally labeled oligodeoxynucleotides.
Mild deprotection schemes were applied to the sulfocyanine-labeled
oligonucleotides.
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Efficient Heterogeneously Palladium-Catalysed Synthesis of
Stilbenes and Bibenzyls
Giuseppe Cusati, Anja Wedig and
Laurent Djakovitch
An alternative heterogeneously palladium catalysed procedure
for the synthesis of functional stilbenes and bibenzyls is
reported. Starting from aryl bromides and using simple commercially
available Pd/C catalyst at a low catalytic rate (1 mol%),
stilbenes are obtained with 30-100% GC-yields and bibenzyls
are produced in a one-pot fashion with 27-100% GC-yields.
The procedure showed, however, some limitations when applied
to strongly deactivated aryl bromides that could be in some
extent overcome by using corresponding iodo derivatives.
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A Short Route to [1,2,3]-Triazolyl Coumarin and Quinolone
Derivatives by Cu(I) Catalyzed 1,3-Dipolar Cycloaddition and
Fluorescence Studies
Krishna C. Majumdar and Shovan
Mondal
Hitherto unreported [1,2,3]-triazolyl coumarin and quinolone
derivatives in good to excellent yields have been expediently
synthesized from 6- and 7-azidocoumarin and 6-azidoquinolone
by copper (I) catalyzed 1,3-dipolar cycloaddition. Azidocoumarins
and azidoquinolones were in turn prepared efficiently from
the corresponding amines. Fluorescence studies of the newly
synthesized [1,2,3]- triazolyl coumarin and quinolone derivatives
are also described.
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A Short and Efficient Synthesis of the Selective H4
Receptor Agonist 4-Methylhistamine
Mirko Rivara, Valentina Zuliani, Pier V.
Plazzi and Fabrizio Bordi
An efficient synthesis of the selective H4
receptor agonist 4-methylhistamine is described. This approach
can be used to prepare, without purification steps and in
high yield, significant quantities of the product, useful
as pharmacological tool to investigate the physiological roles
of the histamine H4 receptor.
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New Solid-Phase Approach to Synthesize a Hyacinthacine Core
Using the L-Proline as a Building Block
Mônica O. Duarte, Guilherme Stedele,
Mariane Pazinatto, Eduardo R. de Oliveira and Vera
L. Eifler-Lima
A new solid-phase synthesis of pyrrolizidine nucleus
related to hyacinthacine core using L-proline as
the starting material is reported. The final step is a new
approach with a cyclization-cleave strategy, which releases
the product from the resin in good yields under Baylis-Hillman
conditions.
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Zirconium Tetrakis(dodecylsulfate) as an Efficient and Recyclable
Lewis Acid-Surfactant-Combined Catalyzed C-C and C-N Bond
Forming Under Mild and Environmentally Benign Conditions
Maasoumeh Jafarpour, Abdolreza Rezaeifard
and Marzieh Aliabadi
A green catalytic method for C-C and C-N bond forming
via Michael addition of aromatic amines and indoles
to electron-deficient olefins using Zirconium tetrakis(dodecylsulfate)
in water under mild conditions with high yields and selectivity
has been developed. The reusability of the catalyst has been
successfully examined without any noticeable loss of its catalytic
activity.
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Facile Regioselective Green Synthesis of Triazolo
[4,3-a] Pyrimidines in Aqueous Medium
Anshu Dandia, Ruby Singh, Dharmendra Singh
and Kapil Arya
Regioselectivity is investigated in multi-component reaction
of amino triazole, carbonyl compounds and α-cyano
esters derivative and exclusive synthesis of triazolopyrimidines
is developed in aqueous medium in excellent yields in shorter
period using microwaves or ultrasonic waves. Path and mechanism
of the reaction has also been discussed. The operational simplicity,
environmental friendly conditions, regioselective formation
of target product, high yield in significantly very short
reaction time, are major benefits.
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