cas 5425-44-5, 2-PHENYL-1,3-DITHIANE | Articles data

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Highly ordered mesoporous functionalized pyridinium protic ionic liquid framework as a highly efficient catalytic system in chemoselective thioacetalization of carbonyl compounds under solvent-free conditions
Dithioacetals are a well-known class of organic compounds as both protecting group for the carbonyl compounds and valuable synthons for organic synthesis. Polysiloxane acidic ionic liquids containing pyridinium trifluoroacetate salts (PMO-Py-IL) as organi
Karimi, Nafiseh,Luque, Rafael,Rajabi, Fatemeh,Voskressensky, Leonid
(2021/10/04)

Esterification or Thioesterification of Carboxylic Acids with Alcohols or Thiols Using Amphipathic Monolith-SO3H Resin
We have developed a method for the esterification of carboxylic acids with alcohols using amphipathic, monolithic-resin bearing sulfonic acid moieties as cation exchange functions (monolith-SO3H). Monolith-SO3H efficiently catalyzed the esterification of aromatic and aliphatic carboxylic acids with various primary and secondary alcohols (1.55.0 equiv) in toluene at 6080 °C without the need to remove water generated during the reaction. The amphipathic property of monolith-SO3H facilitates dehydration due to its capacity for water absorption. This reaction was also applicable to thioesterification, wherein the corresponding thioesters were obtained in excellent yield using only 2.0 equiv of thiol in toluene, although heating at 120 °C was required. Moreover, monolith-SO3H was separable from the reaction mixtures by simple filtration and reused for at least five runs without decreasing the catalytic activity.
Ichihara, Shuta,Ishida, Moeka,Ito, Ryo,Kato, Ayumu,Monguchi, Yasunari,Nakamura, Shinji,Park, Kwihwan,Sajiki, Hironao,Takada, Hitoshi,Wakayama, Fumika,Yamada, Tsuyoshi,Yamada, Yutaro
p. 2702 - 2710
(2022/01/19)

Ni-NiO heterojunctions: a versatile nanocatalyst for regioselective halogenation and oxidative esterification of aromatics
Herein, we report a facile method for the synthesis of Ni-NiO heterojunction nanoparticles, which we utilized for the nuclear halogenation reaction of phenol and substituted phenols usingN-bromosuccinimide (NBS). A remarkablepara-selectivity was achieved for the halogenated products under semi-aqueous conditions. Interestingly, blocking of thepara-position of phenol offeredortho-selective halogenation. In addition, the Ni-NiO nanoparticles catalyzed the oxidative esterification of carbonyl compounds with alcohol, diol or dithiol in the presence of a catalytic amount of NBS. It was observed that the aromatic carbonyls substituted with an electron-donating group favoured nuclear halogenation, whereas an electron-withdrawing group substitution in carbonyl compounds facilitated the oxidation reaction. In addition, the catalyst was magnetically separated and recycled 10 times. The tuned electronic structure at the Ni-NiO heterojunction controlled selectivity and activity as no suchpara-selectivity was observed with commercially available NiO or Ni nanoparticles.
Bhardwaj, Nivedita,Goel, Bharat,Indra, Arindam,Jain, Shreyans K.,Singh, Ajit Kumar,Tripathi, Nancy
p. 14177 - 14183
(2021/08/16)

Catalytic application of sulfamic acid-functionalized magnetic Fe3O4nanoparticles (SA-MNPs) for protection of aromatic carbonyl compounds and alcohols: Experimental and theoretical studies
Protection techniques of functional groups within the structure of organic compounds are important synthetic methods against unwanted attacks from various reagents during synthetic sequences. Acetal and thioacetal groups are well known as protective funct
Khaef, Sepideh,Taherpour, Avat Arman,Yarie, Meysam,Zolfigol, Mohammad Ali
p. 44946 - 44957
(2020/12/30)

An expedient carbon–sulfur bond formation explored through the cellulose sulfonic acid (CSA) catalyzed dithioacetal protection of carbonyl compounds
A facile carbon–sulfur bond formation was observed through the cellulose sulfonic acid (CSA) catalyzed dithioacetal protection of carbonyl compounds. In a preliminary study, the synthesis and characterization of functionalized bio-polymer, cellulose sulph
Kadam, Kailas R.
p. 530 - 541
(2020/07/03)

An uncommon use of irradiated flavins: Br?nsted acid catalysis
We present that thioacetalization of aldehydes can be induced by blue light irradiation in the presence of a catalytic amount of riboflavin tetraacetate (RFTA) under aerobic conditions. Several control experiments have suggested that the reaction is more
Arakawa, Yukihiro,Mihara, Tomohiro,Fujii, Hiroki,Minagawa, Keiji,Imada, Yasushi
supporting information
p. 5661 - 5664
(2020/06/09)

Direct anodic (thio)acetalization of aldehydes with alcohols (thiols) under neutral conditions, and computational insight into the electrochemical formation of the acetals
A versatile protocol for the production of acetals/thioacetals by means of direct electrochemical oxidation is developed here under neutral conditions, providing (thio)acetals with good functional group tolerance and a wide scope for both aldehydes and (thio)alcohols. DFT calculations reveal that direct electron transfer from the anode plays a key role in carbonyl activation during this acid free acetalization process.
Liu, Caiyan,Shen, Yongli,Xiao, Zihui,Yang, Hui,Han, Xue,Yuan, Kedong,Ding, Yi
p. 4030 - 4034
(2019/08/07)

Tandem Addition/Electrocyclization/Benzylation of Alkyl Aryl-1,3-dienes and Aromatic Aldehydes: Access to Highly Substituted Indenes
BF3·Et2O-mediated synthesis of multisubstituted indenes from alkyl aryl-1,3-dienes and aromatic aldehydes through tandem addition/4π-electrocyclization/benzylation via tetrahydroindeno-oxepine/quinone methide followed by an intramole
Mahesh,Nanubolu, Jagadeesh Babu,Sudhakar, Gangarajula
p. 7815 - 7828
(2019/06/24)

Visible-Light Photoredox-Catalyzed Thioacetalization of Aldehydes Under Metal-Free and Solvent-Free Conditions
A first visible-light photoredox-catalyzed thioacetalization of aldehydes under metal-free and solvent-free conditions is described. Under blue LED irradiation, a reactive thiyl radical was initially generated through single-electron oxidation of thiol, w
Du, Kai,Wang, Shao-Chien,Basha, R. Sidick,Lee, Chin-Fa
p. 1597 - 1605
(2018/12/11)

A 2 - substituted - 1, 3 - dithiane derivative of the preparation method
The invention provides a preparation method of a 2-substituted-1,3-dithiane derivative. The preparation method comprises the following steps: adding 1,3-dithiane (CAS:505-23-7) and 1,2-dichloroethane (DCE) or dichloromethane (DCM) into a reaction bottle, adding N-chlorosuccinimide (NCS) under ice-bath condition, and stirring for 0.5-1 h to prepare a 2-chloro-1,3-dithiane solution; and adding an aldehyde or ketone compound and a lewis acid catalyst into the above solution, and reacting to prepare the 2-substituted-1,3-dithiane derivative. By using the 1,3-dithiane solid and different types of aldehyde and keto-carbonyl compounds as raw material and using one or more of ferric trichloride, boron trifluoride diethyl etherate, methanesulfonic acid, aluminum trichloride, ferrous chloride and nickel chloride as catalysts, preparation of the 2-substituted-1,3-dithiane derivative is realized. The catalysts used in the invention are cheap and easily available, dosage of the catalysts is low and pollution of the catalysts is little. The solid raw materials used in the invention can avoid use of fetid toxic 1,3-dimercaptopropane with strong volatility, and the purpose of protecting an experimenter's body and reducing environmental pollution is realized. In addition, the preparation method has advantages of mild reaction condition, high yield, simple operation and the like.
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Paragraph 0019; 0026

(2019/06/26)

Preparing method of 2-substituted-1,3-dithiane derivative
The invention belongs to the technical field of organic synthesis, and particularly discloses a preparing method of a 2-substituted-1,3-dithiane derivative. The preparing method comprises the following steps of adding substrate aldehyde, 1,3-dimercaptopro
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Paragraph 0020-0026

(2018/10/02)

Visible-light promoted dithioacetalization of aldehydes with thiols under aerobic and photocatalyst-free conditions
A novel photocatalyst-free visible-light-mediated dithioacetalization of aldehydes and thiols has been developed. This protocol is operationally simple, mild and atom-economical, which provides an environmental benign access to dithioacetals at room temperature under aerobic conditions.
Xing, Zhimin,Yang, Mingyang,Sun, Haiyu,Wang, Zemin,Chen, Peng,Liu, Lin,Wang, Xiaolei,Xie, Xingang,She, Xuegong
supporting information
p. 5117 - 5122
(2018/11/24)

Modulated photochemical reactivities of: O -acetylated (3′,5′-dimethoxyphenyl)heteroaryl acyloin derivatives under direct irradiation and photo-induced electron transfer conditions
3′,5′-Dimethoxybenzoin esters are important photoremovable protecting groups which form 2-phenylbenzofuran derivatives upon photo-release. We utilized a similar concept to test a photochemical method of installing a benzofuran moiety to the conjugated bac
Bisht, Rajesh,Singh, Saumya,Krishnamoorthy, Kothandam,Nithyanandhan, Jayaraj
p. 835 - 845
(2018/06/21)

Pot-economy autooxidative condensation of 2-Aryl-2-lithio-1,3-dithianes
The autoxidative condensation of 2-aryl-2-lithio-1,3-dithianes is here reported. Treatment of 2-aryl-1,3-dithianes with n-BuLi in the absence of any electrophile leads to condensation of three molecules of 1,3-dithianes and formation of highly functionalized α-thioether ketones orthothioesters in 51-89% yields upon air exposure. The method was further expanded to benzaldehyde dithioacetals, affording corresponding orthothioesters and α-thioether ketones in 48-97% yields. The experimental results combined with density functional theory studies support a mechanism triggered by the autoxidation of 2-aryl-2-lithio-1,3-dithianes to yield a highly reactive thioester that undergoes condensation with two other molecules of 2-aryl-2-lithio-1,3-dithiane.
Vale, Joao R.,Rimpil?inen, Tatu,Siev?nen, Elina,Rissanen, Kari,Afonso, Carlos A. M.,Candeias, Nuno R.
p. 1948 - 1958
(2018/02/23)

Sulfur-Directed Ligand-Free C-H Borylation by Iridium Catalysis
An iridium-catalyzed ortho C-H borylation reaction directed by cyclic dithioacetal moiety is disclosed. A series of borylation products were obtained in moderate to good yields under mild conditions in exclusive mono- and ortho-regioselectivity. Thus, the 1,3-dithiane or 1,3-dithiolane group serves as a remarkable effective directing group for C-H borylation without any ligand assistance. The further transformations of the borylation products are also carried out to change boryl group to other functional groups.
Liu, Li,Wang, Guanghui,Jiao, Jiao,Li, Pengfei
supporting information
p. 6132 - 6135
(2017/11/24)

Mesoporous sBa-15 silica catalyst functionalized with phenylsulfonic acid groups (SbA-15-ph-So3h) as efficient nanocatalyst for chemoselective thioacetalization of carbonyl compounds
In this research a Nano acidic catalyst was prepared and its efficiency on thioacetalization of carbonyl compounds was examined. For this aim we used modified SBA-15 as support, which have been modified by phenolic and sulfonic acid. SBA-15 is a member of
Sedrpoushan, Alireza,Ghazizadeh, Habibollah
p. 112 - 118
(2017/01/18)

Intermolecular Schmidt reaction of alkyl azides with acyl silanes
The first intermolecular Schmidt reaction of alkyl azides with acyl silanes has been designed and realized, producing a range of amides with absolute site selectivity in good to excellent yields. The mechanism of the conversion has been proposed, and the reaction exhibits scope of substrates.
Yu, Chun-Jiao,Li, Rui,Gu, Peiming
supporting information
p. 3568 - 3570
(2016/07/18)

Sulfonated polyanthracene-catalyzed highly efficient and chemoselective thioacetalization of carbonyl compounds and transthioacetalization of acetals and acylals
A straightforward and highly efficient procedure for the thioacetalization of a variety of aldehydes and transthioacetalization of acylals and acetals in good to excellent yields using catalytic amounts of sulfonated polyanthracene (S-PAT) is reported. Th
Fahid,Pourmousavi
p. 16 - 29
(2015/10/20)

Rapid assessment of protecting-group stability by using a robustness screen
An experimentally simple method has been developed to rapidly establish the stability of widely utilized silyl, acetal, and carbamate protecting groups to a given set of reaction conditions. Assessment of up to twelve protecting groups in a single experiment has been demonstrated. Evaluation of this protocol in two unrelated synthetic transformations suggests that this method can be used to select appropriate protecting groups in the design of synthetic routes.
Collins, Karl D.,Ruehling, Andreas,Lied, Fabian,Glorius, Frank
supporting information
p. 3800 - 3805
(2014/04/03)

Solid-supported odorless reagents for the dithioacetalization of aldehydes and ketones
A solid supported, odorless reagent for the dithioacetalization of aldehydes and ketones has been developed. The new reagent provides the dimercaptoalkane equivalent in combination with stoichiometric amounts of immobilized acid and enables the formation of dithianes and dithiolanes from aldehydes without any additives in good to very good yields with high purities. The reaction is chemoselective for aldehydes, but ketones can be reacted to the corresponding dithioketals if an additional Lewis acid such as BF3is added.
Jung,Gr?ssle,Lütjohann,Br?se
supporting information
p. 1036 - 1039
(2016/10/17)

Palladium-catalyzed cross-coupling of 2-aryl-1,3-dithianes
Palladium-catalyzed cross-coupling of aryl bromides with 2-aryl-1,3-dithianes is described. This methodology takes advantage of the relatively acidic benzylic proton of the dithiane, allowing it to act as a competent, polarity-reversed transmetalation reagent. This unique approach affords the ability to employ an orthogonal deprotection strategy, and practical routes to both diaryl ketones and diarylmethanes are illustrated. Cross-coupling of a range of aryl dithianes with aryl bromides, including scope and current limitations, is presented.
Dockrey, Summer A. Baker,Makepeace, Alicia K.,Schmink, Jason R.
supporting information
p. 4730 - 4733
(2015/04/27)

Fe-catalyzed direct dithioacetalization of aldehydes with 2-chloro-1,3-dithiane
Present methods to synthesize 1,3-dithiane molecules require either harsh reaction conditions or highly specialized reagents. We have developed a catalytic dithioacetalization process that directly gains access to the corresponding 1,3-dithianes using aldehydes and 2-chloro-1,3-dithiane in a highly efficient manner. This methodology is beneficial due to mildness of the reaction conditions, and the dithioacetaliation process results in good to excellent yields by using 15 mol % of an iron catalyst.
Lai, Junshan,Du, Wenbin,Tian, Lixia,Zhao, Changgui,She, Xuegong,Tang, Shouchu
p. 4396 - 4399
(2015/01/08)

Catalytic conjugate addition of acyl anion equivalents promoted by fluorodesilylation
The conjugate addition of acyl anion equivalents derived from 2-silyl-1,3-dithianes to α,β-unsaturated ketones and esters has been achieved using a substoichiometric amount of TBAF. High yields and short reaction times are observed for the addition of aryl-1,3-dithianes to a variety of cyclic and acyclic α,β-unsaturated carbonyl acceptors. Observation of the reactive anion by 13C NMR spectroscopy and extension to an asymmetric variant is also presented.
Denmark, Scott E.,Cullen, Lindsey R.
supporting information
p. 70 - 73
(2014/01/23)

SBA-15 functionalized sulfonic acid containing a confined hydrophobic and acidic ionic liquid: A highly efficient catalyst for solvent-free thioacetalization of carbonyl compounds at room temperature
A novel application of SBA-15 functionalized sulfonic acid containing a confined ionic liquid has been introduced to convert various carbonyl compounds to their corresponding dithioacetals and dithioketals at room temperature and under solvent-free condit
Karimi, Babak,Vafaeezadeh, Majid
p. 23207 - 23211
(2013/11/19)

Aluminum hydrogen sulfate [Al(HSO4)3] as an efficient catalyst for the preparation of thioacetals
Aluminum hydrogen sulfate, as a heterogeneous solid acid catalyst, has been used for the mild conversion of carbonyl compounds to their thioacetals using 1,2- and 1,3-dithiol under ambient conditions with short reaction times in high to excellent yield in
Ghashang, Majid
p. 2837 - 2842
(2013/07/26)

The catalytic versatility of low toxicity dialkyltriazolium salts: In situ modification facilitates diametrically opposed catalysis modes in one pot
The ability of triazolium salts to serve as a precatalyst for both an acid and a powerful base/nucleophile (controlled by additives) has been exploited in a process characterised by a unique in situ catalyst modification strategy. The Royal Society of Chemistry 2013.
Myles, Lauren,Gathergood, Nicholas,Connon, Stephen J.
supporting information
p. 5316 - 5318
(2013/06/27)

Silica phenyl sulfonic acid as a solid acid heterogeneous catalyst for chemoselective thioacetalization of carbonyl compounds and dethioacetalization under mild conditions
Silica phenyl sulfonic acid (SPSA) is an effective catalyst for chemoselective thioacetalization of aldehydes in the presence of ketones under neutral conditions. In addition, a simple and an efficient procedure for deprotection of 1,3-dithianes and 1,3-dithiolanes of aromatic, aliphatic, and α,β-unsaturated aldehydes and ketones in the solvent-free to the corresponding parent carbonyl compounds was successfully carried out with SPSA in excellent yields.
Veisi, Hojat,Sedrpoushan, Alireza,Zolfigol, Mohammad Ali,Mohanazadeh, Farajollah,Hemmati, Saba
p. E204-E206
(2013/06/04)

Chemoselective and odorless transthioacetalization of acetals using α-oxo-ketene dithioacetals as thiol equivalents
Using α-oxo-ketene dithioacetals 1a as odorless thiol equivlents, an efficient and odorless transthioacetalization of acetals 2 has been developed. In the presence of MeCOCl in MeOH, the cleavage of 1a commences to generate thiols at both room and reflux temperatures, and the generated thiols then react with acetals 2 to give correspecting thioacetals 3 in good yield. This transthioacetalization is characterized by mild reaction conditions, simple procedure, good yields, and perfect chemoselectivity. It is noteworthy that only a very faint odor of thiols can be perceived during both the reaction and workup.
Yu, Hai-Feng
p. 1280 - 1286
(2013/04/10)

A prototype continuous-flow liquid-liquid extraction system using open-source technology
A prototype continuous-flow liquid-liquid extraction system is reported. By harnessing several open-source software libraries, a computer control script was written using the Python programming language. Using a 'computer-vision' approach, this allowed the computer to monitor the interface level between the organic and aqueous phases using a simple webcam setup and (by dynamically controlling pump flow rate) to keep this interface within defined limits. The system enabled the efficient 'inline' extraction of excess reagent in hydrazone formations, dithiane formations and epoxidations. The initial results of dispersion measurement are also presented.
O'Brien, Matthew,Koos, Peter,Browne, Duncan L.,Ley, Steven V.
scheme or table
p. 7031 - 7036
(2012/10/08)

Synthesis and antimicrobial evaluation of novel platensimycin analogues
Since the isolation of the natural products platensimycin and platencin as new antibiotic lead structures, several total syntheses as well as syntheses of derivatives have been developed. Most of these approaches are very laborious and the target molecule
Plesch, Eva,Bracher, Franz,Krauss, Juergen
experimental part
p. 657 - 662
(2012/09/25)

Synthesis of 1,3-dithiane and 1,3-dithiolane derivatives by tungstate sulfuric acid: Recyclable and green catalyst
An efficient, novel, and environmentally benign procedure for the thioacetalization of aliphatic and aromatic carbonyl compounds in the presence of catalytic amounts of tungstate sulfuric acid under solvent-free conditions to afford 1,3-dithianes and 1,3-
Karami, Bahador,Taei, Mahbubeh,Khodabakhshi, Saeed,Jamshidi, Masih
experimental part
p. 65 - 74
(2012/07/14)

Efficient and chemoselective acetalization and thioacetalization of carbonyls and subsequent deprotection using InF3 as a reusable catalyst
An efficient and chemoselective method for preparation of acetals and dithioacetals of aldehydes and their deprotection under catalysis of InF 3 is described.
Madabhushi, Sridhar,Mallu, Kishore Kumar Reddy,Chinthala, Narsaiah,Beeram, China Ramanaiah,Vangipuram, Venkata Sairam
experimental part
p. 697 - 701
(2012/02/15)

Palladium-catalyzed fluoride-free cross-coupling of intramolecularly activated alkenylsilanes and alkenylgermanes: Synthesis of tamoxifen as a synthetic application
We have demonstrated that intramolecular hypercoordination of a carboxylic acid is a powerful activation strategy for the palladium-catalyzed cross-coupling reaction of trialkyl(vinyl)silanes and trialkyl(vinyl)germanes under fluoride-free conditions. Z-β-Trialkylsilyl- and Z-β- trialkylgermylacrylic acids, synthesized stereoselectively by olefination with ynolates, are highly stable and useful reagents for cross-coupling with a variety of aryl iodides to provide tetrasubstituted olefins possessing different carbon substituents in a stereocontrolled and diversity-oriented manner. An application to a stereoselective synthesis of (Z)-tamoxifen is also reported. Copyright
Matsumoto, Kenji,Shindo, Mitsuru
supporting information; experimental part
p. 642 - 650
(2012/05/04)

Preyssler-type heteropoly acid: A new, mild and efficient catalyst for protection of carbonyl compounds
Preyssler-type heteropoly acid is introduced as a new, mild and efficient catalyst for protection of a variety of carbonyl compounds with 1,3-propane dithiol.
Rahimizadeh, Mohammad,Bazazan, Tahmineh,Shiri, Ali,Bakavoli, Mehdi,Hassani, Hassan
experimental part
p. 435 - 438
(2012/01/03)

Silica-supported phosphorus pentoxide: A reusable catalyst for S,S-acetalization of carbonyl groups under ambient conditions
Phosphorus pentoxide supported on silica gel (P2O 5/SiO2) efficiently acts as a highly active and reusable catalyst for cyclic and non-cyclic S,S-acetalization of a variety of carbonyl compounds under mild, solvent-free an
Shaterian, Hamid Reza,Azizi, Kobra,Fahimi, Nafiseh
experimental part
p. 85 - 91
(2012/01/06)

Thioacetalization of aldehydes and ketones in SDS micelles
Aromatic aldehydes have been successfully converted into their corresponding dithioacetal, dithiolane and dithiane derivatives in excellent yields with thiol (benzyl thiol and thiophenol), 1,2-ethanedithiol and 1,3-propanedithiol using trichloroacetic acid in sodium dodecyl sulfate micelles. The same procedure is applicable to ketones, but they need more time to be converted into their thioacetals. Image Presented.
Bahrami, Kiumars,Khodaei, Mohammad Mehdi,Tajik, Maryam,Soheilizad, Mehdi
experimental part
p. 397 - 403
(2012/06/18)

Dithioacetalization of carbonyl compounds under catalyst-free condition
Protection of carbonyl compounds with 1,3-propanedithiol under a catalyst-free condition in nitromethane as a solvent has been described.
Akhlaghinia, Batool,Makarem, Ata
experimental part
p. 575 - 581
(2012/04/23)

Poly(N-bromobenzene-1,3-disulfonamide) and N,N,N′,N′- tetrabromobenzene-1,3-disulfonamide as a mild and efficient catalyst for chemoselective thioacetalization of carbonyl functions and transthioacetalization reactions
Poly(N-bromobenzene-1,3-disulfonamide) and N,N,N′,N′- tetrabromobenzene-1,3-disulfonamide are effective catalysts for chemoselective dithioacetalization of aldehydes in the presence of ketones under neutral conditions.
Veisi, Hojat,Ghorbani-Vaghei, Ramin,Dadamahaleh, Somayeh Akbari
experimental part
p. 699 - 705
(2011/07/31)

Chemoselective (trans)thioacetalization of carbonyl compounds with a reusable lewis acid-surfactant-combined copper bis(dodecyl sulfate) catalyst in water
A Lewis acid-surfactant-combined copper bis(dodecyl sulfate) [Cu(DS) 2] catalyst served as an efficient and reusable catalyst for the thioacetalization and transthioacetalization of carbonyl compounds and O,O-acetals in water at room temperature. Some of the major advantages of this procedure are high chemoselectivity, ease of operation and purification without any organic solvent, and high yields. Georg Thieme Verlag Stuttgart.
Weng, Shiue-Shien,Chang, Shen-Chun,Chang, Tsuan-Hao,Chyn, Jong-Pyng,Lee, Shu-Wei,Lin, Chao-An,Chen, Fong-Kuang
experimental part
p. 1493 - 1499
(2010/10/03)

1,3-dibromo-5,5-dimethylhydantoin (DBH) as a mild and efficient catalyst for chemoselective thioacetalization of carbonyl compounds and dethioacetalization under mild conditions
Hydantoin bromide is an effective catalyst for chemoselective thioacetalization of aldehydes in the presence of ketones under neutral conditions. In addition, a simple and efficient procedure for the deprotection of 1,3-dithianes and 1,3-dithiolanes of ar
Veisi, Hojat,Amiri, Mostafa,Hamidian, Amir Hossein,Malakootikhah, Javad,Fatolahi, Leila,Faraji, Alireza,Sedrpoushan, Alireza,Maleki, Behrooz,Saremi, Shokufe Ghahri,Noroozi, Mohammad,Bahadoori, Fatemeh,Veisi, Somayeh
experimental part
p. 689 - 696
(2010/06/19)

Catalytic carbon-sulfur bond formation by amphoteric vanadyl triflate: exploring with thia-Michael addition, thioacetalization, and transthioacetalization reactions
A series of thiols have been examined as protic nucleophiles for Michael-type additions to α,β-unsaturated carbonyls as well as double nucleophilic condensations with aldehydes, ketones, and acetals catalyzed by amphoteric, water-tolerant vanadyl triflate under mild and neutral conditions. The newly developed C-S bond formation protocols were carried out smoothly in good to high yields in a highly chemoselective manner.
Chen, Chien-Tien,Lin, Yow-Dzer,Liu, Cheng-Yuan
supporting information; experimental part
p. 10470 - 10476
(2010/02/28)

Silica-PCl5: A novel heterogenous catalyst for simple and efficient chemoselective protection of carbonyl compounds
A simple, efficient and environmentally benign procedure has been developed for chemoselective protection of carbonyl compounds using the newly developed heterogeneous catalyst: Silica-PCl5. A variety of aldehydes and ketones were efficiently c
Pandey, Lokesh Kumar,Pathak, Uma,Tank, Rekha,Mazumder, Avik
experimental part
p. 167 - 171
(2010/07/05)

Propynal equivalents and diazopropyne: Synthesis of all mono-13C isotopomers
Mechanistic and spectroscopic investigations of reactive C 3H2 hydrocarbons necessitated the preparation of diazopropyne isotopomers bearing mono-13C substitution at each of the three unique positions. The diazo compounds and their tosylhydrazone precursors were prepared from the mono-13C isotopomers of propynal (in the form of either the aldehyde or the diethyl acetal). The introduction of 13C-labeling at either alkyne position in propynal utilized the Corey - Fuchs procedure for chain homologation.
Seburg, Randal A.,Hodges, Jonathan A.,McMahon, Robert J.
experimental part
p. 1626 - 1643
(2009/10/17)

Synthesis of benzo[b]furans by palladium-NHC catalyzed ring closure of o-bromobenzyl ketones
The palladium-catalyzed ring closure of aryl o-bromobenzyl ketones, easily accessible from aromatic aldehydes and 2- bromobenzyl bromide, provides a straightforward route to 2-aryl- benzofurans. A study of the ring closure revealed that a heterocyclic car
Farago, Janos,Kotschy, Andras
scheme or table
p. 85 - 90
(2009/06/18)

Hafnium trifluoromethanesulfonate (hafnium triflate) as a highly efficient catalyst for chemoselective thioacetalization and transthioacetalization of carbonyl compounds
(Chemical Equation Presented) A range of carbonyl compounds including aliphatic and aromatic aldehydes and ketones were converted to the corresponding thioacetals in high yields in the presence of a catalytic amount of hafnium trifluoromethanesulfonate (0.1 mol %, room temperature). The mild conditions tolerated various sensitive functional and protecting groups and were racemization-free when applied to α-aminoaldehydes. Transacetalization and chemoselective thioacetalization of aromatic aldehydes in the presence of aliphatic aldehydes and ketones were also documented.
Wu, Yan-Chao,Zhu, Jieping
supporting information; experimental part
p. 9522 - 9524
(2009/04/06)

Chemoselective dithioacetalization and oxathioacetalization of carbonyl compounds using alumina sulfuric acid as catalyst
Carbonyl compounds have been successfully converted into their corresponding dithiolane, dithiane, and oxathiolane derivatives using a catalytic amount of alumina sulfuric acid (Al2O3-SO3H) with excellent yields at room temperature in short reaction times under mild conditions. This simple method is a highly chemoselective procedure for protection of aldehydes in the presence of ketones, and the heterogeneous catalyst can be recovered and reused several times without any loss of its activity. Copyright Taylor & Francis Group, LLC.
Shaterian, Hamid Reza,Hosseinian, Asghar,Ghashang, Majid
experimental part
p. 4097 - 4106
(2009/04/11)

Chemoselective dithioacetalization of carbonyl compounds using magnesium hydrogensulfate as efficient heterogeneous catalyst
Carbonyl compounds have been successfully converted into their corresponding dithiolanes and dithianes derivatives with 1,2-ethanedithiol and 1,3-propanedithiol in excellent yield at room temperature and short reaction times using a catalytic amount of ma
Shaterian, Hamid Reza,Hosseinian, Asghar,Ghashang, Majid,Khorami, Fahimeh
experimental part
p. 2490 - 2501
(2009/08/07)

Efficient method for thioacetalization of carbonyl compounds in the presence of a catalytic amount of benzyltriphenylphosphonium tribromide (BTPTB) under solvent-free conditions
A variety of carbonyl compounds have been successfully converted to the corresponding thioacetal derivatives in good to excellent yields on reaction of carbonyl compounds with 1,2-ethanedithiole, 1,3-propanedithiol, and ethylthiol in the presence of a cat
Hajipour, Abdol Reza,Pourmousavi, Seied A.,Ruoho, Arnold E.
p. 2548 - 2566
(2008/12/22)

Ferric hydrogensulfate as effective and recyclable catalyst for mild dithioacetalization of aldehydes and ketones
Ferric hydrogensulfate has been found to be an extremely efficient and recyclable heterogeneous catalyst for dithioacetalization reactions. Carbonyl compounds have been successfully converted into their corresponding dithiolanes and dithianes derivatives
Shaterian, Hamid Reza,Ahmadian, Hamid Reza,Ghashang, Majid,Doostmohammadi, Razieh,Yarahmadi, Hossein
experimental part
p. 1099 - 1108
(2009/04/07)

Trichloromelamine (TCM) - Catalyzed efficient and selective thioacetalization of aldehydes and transthioacetalization of acetals and oxathioacetals under mild reaction conditions
Trichloromelamine was used effectively as a catalyst for thioacetalization of aldehydes and transthioacetalization of acetals and oxathioacetals under mild and almost neutral reaction conditions. By this method, aldehydes, acetals, and oxathioacetals were selectively protected in the presence of ketones as their 1,3-dithiolanes or 1,3-dithianes. Copyright Taylor & Francis Group, LLC.
Hazarkhani, Hassan
p. 2597 - 2606
(2008/12/22)