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Letters in Organic Chemistry
ISSN: 1570-1786
Letters in Organic Chemistry
Volume 6, Number 8, December 2009
Contents
Editor’s Choice
A Diphenylprolinol TMS Ether/Bile Acid Organocatalytic
System for the Asymmetric Domino Sulfa-Michael/Aldol Condensation
Reactions of 1,4-Dithiane-2,5-diol and Cinnamaldehydes
Pp. 593-597
Nikla Baricordi, Simonetta Benetti, Carmela
De Risi, Marco Fogagnolo, Gian Piero Pollini and
Vinicio Zanirato
[Abstract] [Full
Text Article]
Molecular Recognition of Alkylammonium,
N-Methylpyridinium Cations and Native L-α-Amino
Acids by Water Soluble Penta- and Tetra- Sulfonatocalixarenes
Pp. 598-603
Carmela Bonaccorso, Salvatore Gentile, Fabio
Giuseppe Gulino and Domenico Sciotto
[Abstract] [Full
Text Article]
Synthesis and Optical Properties of 6-Substituted-β-cyclodextrin
Derivatives Pp. 604-612
Ruiyun Guo, Mahuya Bagui, Yongge Wei and
Zhonghua Peng
[Abstract] [Full
Text Article]
Facile One-Pot Regioselective Synthesis
of 2,3-Mannoepoxy-β-
Cyclodextrin Pp. 613-615
Zhizhong Wang and Runhua Lu
[Abstract] [Full
Text Article]
An Efficient Synthesis of Taxotere Side
Chain Pp. 616-618
Th. Joymati Devi, Partha Pratim Saikia and
Nabin C. Barua
[Abstract] [Full
Text Article]
Cation Exchange Resin (Indion 130): An
Efficient, Environment Friendly and Recyclable Heterogeneous
Catalyst for the Biginelli Condensation Pp.
619-623
Akshay M. Pansuriya, Mahesh M. Savant, Chirag
V. Bhuva, Naval Kapuriya, Jyoti Singh and Yogesh
T. Naliapara
[Abstract] [Full
Text Article]
Solid Phase Synthesis of Oxytocin Analogues
Conjugated to Polyamino Polycarboxylic Ligands Pp.
624-629
Luciano Lattuada, Enrico Cappelletti, Mario
De Miranda and Chiara Umbelli
[Abstract] [Full
Text Article]
Gold-Catalyzed Regioselective Hydration
of Homopropargyl Alcohols Followed by Diastereoselective Reduction:
An Easy Access to cis 2,5-Disubstituted Tetrahydrofurans
Pp. 630-636
Thi Xuan Mai Nguyen, Blandine Séon-Méniel,
Jean-Christophe Jullian and Bruno Figadère
[Abstract] [Full
Text Article]
ZnI2-Catalyzed
Cyanation of Acyl Chlorides with TMS-CN: An Interesting Role
of Iodine Pp. 637-641
Wei Zeng, Jingya Yang, Bo Meng, Bo Zhang,
Mingzhe Jiang and Fu Xue Chen
[Abstract] [Full
Text Article]
The Synthesis, Reactivity and NMR Investigation
on 15N Thiophospho-ramidates
Pp. 642-647
Tomasz Ruman, Karolina Dlugopolska, Agata
Jurkiewicz, Dagmara Kramarz, Tomasz Fraczyk, Andrzej Les and
Wojciech Rode
[Abstract]
[Supplementary
Material] [Full
Text Article]
Facile Preparation of N-Tosyl-L-Phenylalanine
Chloromethyl Ketone Pp. 648-649
Bing-Lei Gao, Shu-Tao Ma and Zhao-Peng
Liu
[Abstract] [Full
Text Article]
Reaction of Atomic Carbon with Isomeric
Cresols Pp. 650-653
Ilkay Sökmen, Abdulilah Ece, Bülent
Düz and Fatma Sevin
[Abstract] [Supplementary
Material] [Full
Text Article]
Iodine-Alumina Catalyzed Aza- Michael
Addition under Solvent Free Conditions Pp.
654-658
Monmi Saikia, Dwipen Kakati, Maria Stalin
Joseph and Jadab Chandra Sarma
[Abstract] [Full
Text Article]
Labeling of Oligopeptides with Luminescent
Lanthanide(III) Chelates on Solid Phase Pp.
659-663
Jari Peuralahti, Lassi Jaakkola, Harri Hakala,
Veli-Matti Mukkala and Jari Hovinen
[Abstract] [Full
Text Article]
Iron Trichloride Catalyzed One-Pot Synthesis
of Substituted Oxazoles from Propargylic Acetates and Amides
under Microwave Irradiation Pp. 664-668
Wen-Wen Xu, Min Lin, Yang Huang, Li Chen
and Zhuang-Ping Zhan
[Abstract] [Full
Text Article]
Novel Derivatives of 1,3-Dimethyl-5-methylenebarbituric
Acid Pp. 669-672
Kamal Sweidan, Qutaiba Abu-Salem, Ahmed
Al-Sheikh and Ghassan Abu Sheikha
[Abstract]
[Full
Text Article]
Abstracts
[Back to top] [Full
Text Article]
A Diphenylprolinol TMS Ether/Bile Acid Organocatalytic System
for the Asymmetric Domino Sulfa-Michael/Aldol Condensation
Reactions of 1,4-Dithiane-2,5-diol and Cinnamaldehydes
Nikla Baricordi, Simonetta Benetti, Carmela
De Risi, Marco Fogagnolo, Gian Piero Pollini and
Vinicio Zanirato
Organocatalytic asymmetric domino sulfa-Michael/aldol
condensation reactions between 1,4-dithiane-2,5-diol (the
dimer of mercaptoacetaldehyde) and cinnamaldehydes were efficiently
promoted by (S)-diphenylprolinol TMS ether in the presence
of bile acid derivatives, leading to hitherto unknown 4,5-dihydrothiophene-2-carbaldehydes
in moderate to good yields and good enantioselectivities.
[Back to top]
[Full
Text Article]
Molecular Recognition of Alkylammonium, N-Methylpyridinium
Cations and Native L-α-Amino
Acids by Water Soluble Penta- and Tetra- Sulfonatocalixarenes
Carmela Bonaccorso, Salvatore Gentile, Fabio
Giuseppe Gulino and Domenico Sciotto
The inclusion of ethylammonium, N-methylpyridinium
cations and native L-α-amino
acids by the water-soluble pentasulfonatocalix[5]arene 1
has been investigated at neutral pH by 1H
NMR. The complexation behavior has been compared with that
of the homologous tetrasulfonatocalix[4]arene 2.
Unlike host 2, host 1 exhibits
high selectivity in the recognition of the investigated guests.
[Back to top] [Full
Text Article]
Synthesis and Optical Properties of 6-Substituted-β-cyclodextrin
Derivatives
Ruiyun Guo, Mahuya Bagui, Yongge Wei and
Zhonghua Peng
β-Cyclodextrin
derivatives with varying lengths of π-conjugated
arms have been synthesized. Their structures have been confirmed
by 1H NMR, elemental analysis,
mass spectrometry and X-ray crystal structure determination.
Their self-inclusion properties are evaluated using Circular
Dichroism, 1D and 2D 1H NMR
measurements. It is found that, when the length of the π-conjugated
arm is extended from 4 to 5
and to 6, the self-inclusion of the π-conjugated
arm to the CD ring is enhanced. The effect of the self-inclusion
on the optical properties of the CD-linked π-conjugated
systems has been explored. Stronger inclusion leads to enhanced
excitation-energy transfer.
[Back to top] [Full
Text Article]
Facile One-Pot Regioselective Synthesis of 2,3-Mannoepoxy-β-
Cyclodextrin
Zhizhong Wang and Runhua Lu
A simple method for the straightforward regioselective
synthesis of 2,3-mannoepoxy-β-cyclodextrin,
which is a valuable precursor for further functionalization
of β-cyclodextrin,
is achieved in one pot at a moderate yield.
[Back to top] [Full
Text Article]
An Efficient Synthesis of Taxotere Side Chain
Th. Joymati Devi, Partha Pratim Saikia and
Nabin C. Barua
An efficient synthesis of taxotere side chain has
been achieved using Shibasaki’s asymmetric Henry reaction
as the key step.
[Back to top] [Full
Text Article]
Cation Exchange Resin (Indion 130): An Efficient, Environment
Friendly and Recyclable Heterogeneous Catalyst for the Biginelli
Condensation
Akshay M. Pansuriya, Mahesh M. Savant, Chirag
V. Bhuva, Naval Kapuriya, Jyoti Singh and Yogesh
T. Naliapara
Ion exchange resin catalyzed multicomponent Biginelli
reaction is studied for the synthesis of 3,4-dihydropyrimidin-2-ones.
Among the various solid acid catalysts Indion-130 was found
to be most efficient, recyclable and environmentally benign
heterogeneous catalyst regarding reaction time, yield and
ease of work up procedure.
[Back to top] [Full
Text Article]
Solid Phase Synthesis of Oxytocin Analogues Conjugated to
Polyamino Polycarboxylic Ligands
Luciano Lattuada, Enrico Cappelletti, Mario
De Miranda and Chiara Umbelli
An easy solid phase synthesis of oxytocin analogues
conjugated to polyaminopolycarboxylic ligand, such as diethylenetriaminepentaacetic
acid (DTPA) and tetraazacyclododecanetetraacetic acid (DOTA)
is reported. These new products can be labeled with suitable
radiometals (e.g. 90Y, 111In,
177Lu), giving rise to radiopharmaceuticals
with potential application in imaging and/or therapy of tumors
over-expressing oxytocin receptors.
[Back to top] [Full
Text Article]
Gold-Catalyzed Regioselective Hydration of Homopropargyl Alcohols
Followed by Diastereoselective Reduction: An Easy Access to
cis 2,5-Disubstituted Tetrahydrofurans
Thi Xuan Mai Nguyen, Blandine Séon-Méniel,
Jean-Christophe Jullian and Bruno Figadère
A gold (III)-catalyzed hydration of homopropargyl alcohols
led to the corresponding γ-hydroxy
ketones, which were directly reduced by Ph3SiH
in the presence of a Lewis acid, to afford the expected 2,5-disubstituted
tetrahydrofurans as a diastereomeric mixture. NMR analysis
of the compounds so obtained allowed us to confirm that the
cis isomers were the major isomers that can be used
for the preparation of new products.
[Back to top]
[Full
Text Article]
ZnI2-Catalyzed Cyanation
of Acyl Chlorides with TMS-CN: An Interesting Role of Iodine
Wei Zeng, Jingya Yang, Bo Meng, Bo Zhang,
Mingzhe Jiang and Fu Xue Chen
Both aliphatic and aromatic acyl cyanides have been synthesized
with TMSCN and acyl chloride with ZnI2
(0.5 mol%). However the in situ generated I2
is proposed accounting for the formation of by-product O-TMS
enolate at high catalyst loading rather than 0.5 mol%. Asymmetric
reduction of benzoyl cyanide with borane has been explored
in 82% yield and 24% ee.
[Back to top] [Supplementary
Material] [Full
Text Article]
The Synthesis, Reactivity and NMR Investigation on 15N
Thiophospho-ramidates
Tomasz Ruman, Karolina Dlugopolska, Agata
Jurkiewicz, Dagmara Kramarz, Tomasz Fraczyk, Andrzej Les and
Wojciech Rode
Novel 15N-isotope enriched
potassium and diammonium thiophosphoramidates were synthesized
and their spectroscopic properties, along with reactivity
towards several compounds, including histidine, thymidine,
glucose and 2-deoxyribose are presented. The application of
quantum mechanical DFT calculations for estimation of 31P
NMR chemical shifts for several thiophosphoramidate ions and
its derivatives are also discussed.
[Back to top] [Full
Text Article]
Facile Preparation of N-Tosyl-L-Phenylalanine Chloromethyl
Ketone
Bing-Lei Gao, Shu-Tao Ma and Zhao-Peng
Liu
A method for the facile preparation of N-tosyl-L-phenylalanine
chloromethyl ketone was developed. L-Phenylalanine was tosylated
and converted to the activated ester of p-nitrophenol.
Subsequent reaction with dimethylsulfoxonium methylide and
treatment with lithium chloride and methanesulfonic acid afforded
the α-chloroketone.
This practical procedure avoided the use of toxic and explosive
diazomethane.
[Back to top] [Supplementary
Material] [Full
Text Article]
Reaction of Atomic Carbon with Isomeric Cresols
Ilkay Sökmen, Abdulilah Ece, Bülent
Düz and Fatma Sevin
Reaction of atomic carbon with isomeric cresols generates
methyltropones and xylenols. Methyltropone to xylenol ratio
was found to be highest for m-cresol and lowest for p-cresol.
Stability of singlet carbenes produced after insertion of
atomic carbon into C-H bonds of cresols plays an important
role in the observed ratios.
[Back to top] [Full
Text Article]
Iodine-Alumina Catalyzed Aza- Michael Addition under Solvent
Free Conditions
Monmi Saikia, Dwipen Kakati, Maria Stalin
Joseph and Jadab Chandra Sarma
An efficient aza-Michael addition of amines to a variety
of activated olefins was carried out under solvent free conditions
using iodine-alumina as a catalyst at room temperature or
under microwave irradiation (in case of solid) in high yield.
[Back to top] [Full
Text Article]
Labeling of Oligopeptides with Luminescent Lanthanide(III)
Chelates on Solid Phase
Jari Peuralahti, Lassi Jaakkola, Harri Hakala,
Veli-Matti Mukkala and Jari Hovinen
Synthesis of a building block based on 6,6’-(1H-pyrazole-1,3-diyl)bis(pyridine)
(3) that allows introduction of photoluminescent
lanthanide(III) chelates to the synthetic oligopeptides on
solid phase using the standard Fmoc chemistry is described.
Since the ligand based on (3) forms luminescent
chelates with Eu3+, Sm3+,
Tb3+ and Dy3+
ions, the ligand is highly useful for multiparametric homogenous
assays simplifying considerably the preparation of chelates
needed in these applications.
[Back to top] [Full
Text Article]
Iron Trichloride Catalyzed One-Pot Synthesis of Substituted
Oxazoles from Propargylic Acetates and Amides under Microwave
Irradiation
Wen-Wen Xu, Min Lin, Yang Huang, Li Chen
and Zhuang-Ping Zhan
A rapid and efficient procedure under microwave irradiation,
using silica gel-supported reagents for the synthesis of substitued
oxazoles has been developed through iron trichloride catalyzed
propargylation/cycloisomerization tandem reaction of propargylic
acetates and amides.
[Back to top] [Full
Text Article]
Novel Derivatives of 1,3-Dimethyl-5-methylenebarbituric Acid
Kamal Sweidan, Qutaiba Abu-Salem, Ahmed
Al-Sheikh and Ghassan Abu Sheikha
The ability of the pyridinium adduct of 1,3-dimethyl-5-methylenebarbituric
acid (2) to undergo nucleophilic substitution
reaction has been examined. Various types of nucleophiles,
including cyanide, barbiturate, sulfide anions and 1,2-bis(diphenylphosphino)ethane
substitute the pyridinium fragment in 2 leading
to synthesis of new organic derivatives.
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