- Copper-Catalyzed Multicomponent Reaction of DABCO·(SO2)2, Alcohols, and Aryl Diazoniums for the Synthesis of Sulfonic Esters
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A Cu-catalyzed multicomponent cascade reaction of DABCO·(SO2)2 (DABSO), alcohol, and aryl diazonium tetrafluoroborate was developed which afforded sulfonic esters in moderate to good chemical yields. In this reaction, the SO2 surrogate DABSO was used for the first time in the synthesis of sulfonic aliphatic esters. This multicomponent reaction was carried out under mild conditions and tolerated a wide range of substrates, which provides a new and efficient strategy for the synthesis of sulfonic esters.
- Wang, Yang,Deng, Lingling,Deng, Yu,Han, Jianlin
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p. 4674 - 4680
(2018/04/26)
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- Propanolysis of arenesulfonyl chlorides: Nucleophilic substitution at sulfonyl sulfur
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We have studied the mechanism of solvolysis of arenesulfonyl chlorides by propan-1-ol and propan-2-ol at 303-323 K. Kinetic profiles were appropriately fit by first-order kinetics. Reactivity increases with electron-donating substituents. Ortho-alkyl substituted derivatives of arenesulfonyl chlorides show increased reactivity, but the origin of this “positive” ortho-effect remains unclear. Likely, ortho-methyl groups restrict rotation around the C-S bond, facilitating the attack of the nucleophile. No relevant reactivity changes have been found with propan-1-ol and propan-2-ol in terms of nucleophile steric effect. The existence of isokinetic relationships for all substrates suggests a single mechanism for the series. Solvolysis reactions of all substrates in both alcohols show isokinetic temperatures (Tiso) close to the working temperature range, which is an evidence of the process being influenced by secondary reactivity factors, likely of steric nature in the TS. Solvation plays a relevant role in this reaction, modulating the reactivity. In some cases, the presence of t-Bu instead of Me in para- position leads to changes in the first solvation shell, increasing the energy of the reaction (ca. 1?kJ·mol?1). The obtained results suggest the same kinetic mechanism of solvolysis of arenesulfonyl chlorides for propan-1-ol and propan-2-ol, as in MeOH and EtOH, where bimolecular nucleophilic substitution (SN2) takes place with nucleophilic solvent assistance of one alcohol molecule and the participation of the solvent network involving solvent molecules of the first solvation shell.
- Iazykov, Mykyta,Canle, Moisés,Santaballa, J. Arturo,Rublova, Ludmila
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- Iodine-induced synthesis of sulfonate esters from sodium sulfinates and phenols under mild conditions
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An iodine-induced synthesis of sulfonate esters via cross-coupling reactions of sodium sulfinates with phenols is reported. This synthetic route is low-cost, facile, green and efficient, and could afford the target products with good to excellent yields u
- Gao, Jian,Pan, Xiaojun,Liu, Juan,Lai, Junyi,Chang, Liming,Yuan, Gaoqing
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p. 27439 - 27442
(2015/03/31)
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- New process for the production of alkyltosylate from alcohol and para-toluene sulfonic acid
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The present invention relates to a new method for producing an alkyltosylate derivative which plays an important role in transforming a hydroxy group of alcohol into other usage intermediate in a process of synthesizing core intermediates in a fine chemical field such as medicines, agricultural chemicals, dyes, electronic materials, etc. The present invention, as compared with previous technologies which has a long preprocess time for acquiring a catalyst to activate para-toluene sulfonic acid and needs an intense reaction condition in spite of using the catalyst, provides the new method for producing the alkyltosylate derivative having a characteristic of activating the para-toluene sulfonic acid under a warm condition equal to or lower than 25anddeg;C by making the para-toluene sulfonic acid react with the bis(trichloromethyl)carbonate, tribasic potassium phosphate and triethylamine with an amount of catalyst, and then making the para-toluene sulfonic acid react with alcohol, thereby contributing greatly to related industries such as dyes, agricultural chemicals, medicines, electronic materials, etc.COPYRIGHT KIPO 2015
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Paragraph 0026; 0027
(2016/12/16)
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- Synthesis of structural analogues of hexadecylphosphocholine and their antineoplastic, antimicrobial and amoebicidal activity
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Twelve derivatives of hexadecylphosphocholine (miltefosine) were synthesized to determine how the position and length of the alkyl chain within the molecule influence their biological activities. The prepared alkylphosphocholines have the same molecular formula as miltefosine. Activity of the compounds was studied against a spectrum of tumour cells, two species of protozoans, bacteria and yeast. Antitumour efficacy of some alkylphosphocholines measured up on MCF-7, A2780, HUT-78 and THP-1 cell lines was higher than that of miltefosine. The compounds showed antiprotozoal activity against Acanthamoeba lugdunensis and Acanthamoeba quina. Some of them also possess fungicidal activity against Candida albicans equal to miltefosine. No antibacterial activity was observed against Staphylococcus aureus and Escherichia coli. A difference in position of a long hydrocarbon chain within the structure with maximum efficacy was observed for antitumour, antiprotozoal and antifungal activity.
- Timko, Luká?,Fischer-Fodor, Eva,Garajová, Mária,Mrva, Martin,Chereches, Gabriela,Ondriska, Franti?ek,Bukovsky, Marián,Luká?, Milo?,Karlovská, Janka,Kubincová, Janka,Devínsky, Ferdinand
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p. 263 - 273
(2015/05/26)
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- SYNTHESIS OF CHIRALLY PURIFIED SUBSTITUTED BENZOTHIAZOLE DIAMINES
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Methods for preparing chirally purified substituted 4,5,6,7-tetrahydro-benzotiazole diamines such as, for example, (6R)2-amino-4,5,6,7-tetrahydro-6-(propylamino)benzothiazole and purifying a dominant enantiomer of substituted 4,5,6,7-tetrahydro-benzotiazole diamines from entantiomerically enriched mixtures of substituted 4,5,6,7-tetrahydro-benzotiazole diamines are provided herein.
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Page/Page column 52
(2011/10/03)
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- Copper-catalyzed cross-coupling reaction of organoboron compounds with primary alkyl halides and pseudohalides
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Non-activated alkyl electrophiles, including alkyl iodides, bromides, tosylates, mesylates, and even chlorides, underwent copper-catalyzed cross-coupling with aryl boron compounds and alkyl 9-BBN reagents (see scheme; 9-BBN=9-borabicyclo[3.3.1]nonane). The reactions proceed with practically useful reactivities and thus complement palladium- and nickel-catalyzed Suzuki-Miyaura coupling reactions of alkyl halides.
- Yang, Chu-Ting,Zhang, Zhen-Qi,Liu, Yu-Chen,Liu, Lei
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supporting information; experimental part
p. 3904 - 3907
(2011/05/15)
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- COMPOSITIONS AND METHODS OF USING (R)-PRAMIPEXOLE
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Pharmaceutical compositions of (R)-pramipexole and one or more secondary therapeutic agents such as, for example, dopamine agonists, dopaminergic agonists, COMT inhibitors, MOA inhibitors, excitatory amino acid antagonists, growth factors, neurotrophic factors, antioxidants, anti-inflammatory agents, immunomodulators, anti-glutamatergics, ion channel blockers, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonists, heat shock protein inducers/ protein disaggregators and downregulators, monoamine oxidase type B (MOAB) inhibitors, multi-target agents, kinase inhibitors, Bcl inducers, histone deacetylase (HDAC) mediators, glial modulators, mitochondrial energy promoting agents, myostatin inhibitors, caspase inhibitors and combinations thereof or those related to mitochondrial dysfunction or increased oxidative stress are disclosed.
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Page/Page column 101
(2010/04/03)
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- Design, synthesis, and structure-affinity relationships of regioisomeric N-benzyl alkyl ether piperazine derivatives as σ-1 receptor ligands
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A series of N-(benzofuran-2-ylmethyl)-N′-benzylpiperazines bearing alkyl or fluoroalkyl aryl ethers were synthesized and evaluated at various central nervous system receptors. Examination of in vitro σ1 {[3H](+)-pentazocine} and σ2 ([3H]DTG) receptor binding profiles of piperazines 11-13 and 25-36 revealed several highly potent and σ1 selective ligands, notably, N-(benzofuran-2- ylmethyl)-N′-(4′-methoxybenzyl)piperazine (13, Ki = 2.7 nM, σ2/σ1 = 38) and N-(benzofuran-2-ylmethyl)- N′-(4′-(2″-fluoroethoxy)benzyl)piperazine (30, Ki = 2.6 nM, σ2/σ1 = 187). Structural features for optimal σ1 receptor affinity and selectivity over the σ2 receptor were identified. On the basis of its favorable log D value, 13 was selected as a candidate for the development of a σ1 receptor positron emission tomography radiotracer. [ 11C]13 showed high uptake in the brain and other σ receptor-rich organs of a Papio hamadryas baboon. The in vivo evaluation of [11C]13 indicates that this radiotracer is a suitable candidate for imaging the σ1 receptor in neurodegenerative processes.
- Moussa, Iman A.,Banister, Samuel D.,Beinat, Corinne,Giboureau, Nicolas,Reynolds, Aaron J.,Kassiou, Michael
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experimental part
p. 6228 - 6239
(2010/11/02)
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- Amphiphilic organocatalyst for schotten-baumann-type tosylation of alcohols under organic solvent free condition
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A Tosylation of primary alcohol with tosyl chloride was performed effectively with an W-hexadecylimidazole catalyst in water containing K 2CO3 aggregation of the catalyst carrying a hydrophobic methylene chain worked as a substitute for organic solvent.
- Asano, Keisuke,Matsubara, Seijiro
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supporting information; experimental part
p. 1757 - 1759
(2009/09/06)
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- A simple and efficient method for sulfonylation of amines, alcohols and phenols with cupric oxide under mild conditions
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Cupric Oxide efficiently catalyzed the synthesis of sulfonamides and sulfonic esters. This method has been applied to a variety of substrates including nucleophilic and sterically-hindered amines, alcohols and phenols with excellent yields of sulfonamides and sulfonic esters. The remarkable selectivity under mild and neutral conditions of this commercially available inexpensive catalyst is an attractive feature of this method.
- Meshram,Patil, Vishvanath D.
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scheme or table
p. 1117 - 1121
(2009/05/27)
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- Stereoselective synthesis of bioactive isosteviol derivatives as α-glucosidase inhibitors
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Considerable interest has been attracted in isosteviol and its derivatives because of their large variety of pharmacological activities. In this project, a series of novel compounds containing hydroxyl, hydroxymethyl group and heteroatom-containing frameworks fused with isosteviol structure were synthesized and evaluated as α-glucosidase inhibitors, aimed at clarifying the structure-activity correlation. The results indicated that these isosteviol derivatives were capable of inhibiting in vitro α-glucosidase with moderate to good activities. Among them, indole derivative 15b exhibited the highest activities and thus may be exploitable as a lead compound for the development of potent α-glucosidase inhibitors.
- Wu, Ya,Yang, Jing-Hua,Dai, Gui-Fu,Liu, Cong-Jun,Tian, Guo-Qiang,Ma, Wen-Yan,Tao, Jing-Chao
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experimental part
p. 1464 - 1473
(2009/09/05)
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- Application of alkoxy-λ6-sulfanenitriles as strong alkylating reagents
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Alkoxy-λ6-sulfanenitriles were found to be versatile alkylating reagents toward various nucleophiles bearing at least one proton such as methanol, phenol, thiophenols, carboxylic acids, ptoluenesulfonic acid, hydrochloric acid, and primary and secondary amines. Reactivity of the alkoxy group of the λ6-sulfanenitriles showed an opposite trend to the usual SN2 character, i.e. Me (la), Pr (1b), and Bu (1d) ? i-Pr (1c). In the presence of p-TsOH, alkyl tosylates were predominantly formed instead of the alkylation products of nucleophiles. In addition, even a sterically hindered substrate, neopentyloxy-λ6-sulfanenitrile, was found to undergo an SN2 reaction toward thiophenol without any rearrangement product to give neopentyl phenyl sulfide in good yield.
- Hao, Wei,Fujii, Takayoshi,Dong, Tiaoling,Wakai, Youko,Yoshimura, Toshiaki
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p. 193 - 198
(2007/10/03)
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- Synthesis of a calix[4]arene derivative for isolation of a stable cation radical salt for use as a colorimetric sensor of nitric oxide
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We have designed and synthesized a modified calixarene derivative (1) that allows, for the first time, the isolation of a stable cation radical salt that binds a single molecule of nitric oxide deep within its cavity with remarkable efficiency (KNO >108 M-1), as demonstrated by isolation of a crystalline complex [1, NO]+ and its characterization by X-ray crystallography as well as by optical spectroscopy. Furthermore, the ready accessibility of the calixarene cation radical will allow the exploration of its use for developing efficient sensing devices for nitric oxide based on the accompanied color changes. Copyright
- Rathore, Rajendra,Abdelwahed, Sameh H.,Guzei, Ilia A.
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p. 13582 - 13583
(2007/10/03)
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- Photophysics of cyanine dyes on surfaces: Laser-induced photoisomer emission of 3,3′-dialkylthiacarbocyanines adsorbed on microcrystalline cellulose
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The photophysics of three thiacarbocyanine dyes, 3,3′-dimethylthiacarbocyanine iodide (DMTCC), 3,3′-diethylthiacarbocyanine iodide (DETCC), and 3,3′-dipropylthiacarbocyanine iodide (DPTCC) was studied when adsorbed on microcrystalline cellulose in the concentration range from 5.0 · 10-4 to 10.0 μmol g-1. Using ground-state diffuse reflectance absorption technique, only H aggregate formation was detected for all the probes. The amount of aggregate formed depends on the hydration degree of the sample, always decreasing with sample dryness. The fluorescence quantum yields for all the adsorbed dyes are one order of magnitude higher than those observed in nonviscous solvents, being 0.98 for DMTCC, 0.96 for DETCC, and 0.63 for DPTCC. Laser-induced fluorescence emissions were recorded (using an intensified-charge-coupled-device detection system) as a function of the laser power, showing that for dry concentrated samples irradiated with high laser intensity, a second fluorescence emission band (bathochromically shifted relative to the monomer emission) was detected. This emission shows a supralinear dependence on laser power. The new emissions here detected arise from fluorescent photoisomers formed via singlet monomers, by a two-photon absorption process.
- Oliveira, Anabela S.,Almeida, Paulo,Ferreira, Luis Filipe Vieira
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p. 459 - 473
(2007/10/03)
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- Process for preparation of oxyglutaric acid ester derivatives
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A process for preparing an oxyglutaric acid ester derivative of the formula: STR1 in which each of R1 and R2 is C1-5 alkoxy, C1-7 aralkyloxy, C7-9 halogenated aralkyloxy or phenyl, R4 is a hydroxyl-protecting group, and R5 is C1-10 alkyl which may have a substituent, comprises the steps of reacting a methyl phosphonate derivative or methyl phosphine oxide derivative with an oxyglutaric acid mono-ester to give a reaction product which comprises an oxyglutaric acid derivative having a phosphorus-containing group and a pentenedioic acid mono-ester (by-product), removing the pendenedioic acid mono-ester from the reaction product to isolate the oxyglutaric acid derivative, and converting the isolated oxyglutaric acid derivative into the oxyglutaric acid ester derivative. A process for obtaining an optically active oxyglutaric acid ester derivative is also disclosed.
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- Scope and utility of a new soluble copper catalyst [CuBr-LiSPh-LiBr-THF]: A comparison with other copper catalysts in their ability to couple one equivalent of a Grignard reagent with an alkyl sulfonate
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A mixture of equal amounts of CuBr-SMe2, LiBr, and LiSPh in THF at 0°C furnished a new soluble copper catalyst that was highly efficient at coupling primary, secondary, tertiary, aryl, vinyl, and allylic Grignard reagents to primary tosylates and primary Grignard reagents to secondary tosylates and mesylates, all with the use of only 1 equiv of Grignard reagent. The new catalyst was shown to be much more reactive than copper catalysts CuBr and Li2CuCl4 and more efficient in the transference of secondary and tertiary alkyl groups than lower order cuprates (Gilman reagents) and demonstrated more reactivity than the lower order cuprates with its ability to couple primary Grignard reagents to secondary sulfonates. The Grignard reagent/catalyst system was compatible with an ester functionalized tosylate, thus proving to be more chemoselective than a Grignard reagent without the catalyst. The catalyst exhibited good reactivity below room temperature, and with the addition of 6% v/v of HMPA to the catalyst solution, excellent yields of coupled product were obtained within a 25-67°C temperature range. 1H NMR demonstrated that the catalyst solution consisted of several species that most likely were composed of copper ligated with thiophenol, THF, and LiBr in aggregated forms.
- Burns, Dennis H.,Miller, Jeffrey D.,Chan, Ho-Kit,Delaney, Michael O.
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p. 2125 - 2133
(2007/10/03)
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- REACTION OF PHOSPHORUS OXYACID ESTERS WITH p-TOLUENESULFONIC ACID
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The reaction of primary alkyl esters of phosphorus oxyacids with p-toluenesulfonic acid (TsOH) in refluxing solvents gave the corresponding p-toluenesulfonates (TsOR).We found that the secondary alkyl esters reacted with TsOH at lower temperature (r.t.-40 deg C) to afford TsORs in good yields.It is suggested that sulfonic acids may be useful for the selective dealkylation of mixed esters.Keywords-p-toluenesulfonic acid; p-toluenesulfonate; trialkyl phosphate; trialkyl phosphite; dialkyl phenylphosphonate; transesterification; dealkylation; solvolysis.
- Nitta, Yoshihiro,Arakawa, Yasushi,Ueyama, Naoto
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p. 2710 - 2718
(2007/10/02)
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- Benz (c) fluoran compounds and recording sheet containing them
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Novel benz[c]fluoran compounds such as 2-phenylamino-8-diethylamino-benz[c]fluoran, 2-(2',4',6'-trimethylphenylamino)-8-diethylamino-benz[c]fluoran and N-[8-diethylaminobenz[c]fluoran-2-yl]-N-[6-diethylaminofluoran-2-yl]amine, which are useful as a coloring material for record material systems such as pressure-sensitive copying paper or heat-sensitive copying paper, wherein colored images formed by an electron-donoracceptor color-forming reaction between coloring material and acidic material.
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- Chromogenic compounds and method for preparation thereof
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Chromogenic compounds for use in pressure sensitive recording sheets represented by the formula: SPC1 Are disclosed, wherein R1 and R2 are independently, hydrogen substituted or unsubstituted lower alkyl, aliphatic acyl, phenyl substituted aliphatic acyl, benzoyl, aralky, phenyl (the benzene nuclei of those substituents may be further substituted by chlorine, bromine, lower alkyl, lower alkoxy or nitro), allyl, allyl substituted by lower alkyl or phenyl, propargyl, or propargyl substituted by lower alkyl or a phenyl; R3 and R4 are independently lower alkyl, benzyl and phenyl (the benzene nuclei or those substiutents may be further substituted by chlorine, bromine, lower alkyl or lower alkoxy), either R1 or R2 being other than hydrogen when R3 and R4 are both ethyl groups.
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