- 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
-
-
Read Online
- Nickel Hydride Catalyzed Cleavage of Allyl Ethers Induced by Isomerization
-
This report discloses the deallylation of O - and N -allyl functional groups by using a combination of a Ni-H precatalyst and excess Bronsted acid. Key steps are the isomerization of the O - or N -allyl group through Ni-catalyzed double-bond migration followed by Bronsted acid induced O/N-C bond hydrolysis. A variety of functional groups are tolerated in this protocol, highlighting its synthetic value.
- Kathe, Prasad M.,Berkefeld, Andreas,Fleischer, Ivana
-
supporting information
p. 1629 - 1632
(2021/02/09)
-
- Phosphorylated Polyacrylonitrile Fibers as an Efficient and Greener Acetalization Catalyst
-
A novel solid acid catalyst (PANEAPF) is developed by immobilization of phosphoric acid on polyacrylonitrile fiber through covalent bonding. Various characterization techniques such as elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), etc. are utilized to confirm the successful grafting and the stability of the fiber catalysts during application. PANEAPF shows high catalytic activity in the acetalization of aldehydes owing to the high utilization efficiency of its functionalized acid sites. In addition, the strong polarity micro-environment in the surface layers of PANEAPF make it highly suitable for catalytic application in both water and alcohol. Furthermore, the fiber catalyst can be applied to the acetalization of aldehydes in a continuous-flow process at room temperature, and shows excellent reactivity and superior recyclability (over 20 times). The many advantages of PANEAPF such as simple preparation, convenient regulation of acid amount, high durability, and eco-friendly process make it very attractive for fixed-bed reactors in the chemical industry.
- Xu, Gang,Cao, Jian,Zhao, Yali,Zheng, Lishuo,Tao, Minli,Zhang, Wenqin
-
supporting information
p. 2565 - 2575
(2017/09/25)
-
- 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)
-
- 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
-
-
- Efficient thioacetalisation of carbonyl compounds
-
The thioacetalisation of a variety of heterocyclic, aromatic, and aliphatic carbonyl compounds (1 mmol) with ethane-1,2-dithiol (1 mmol) using silica sulphuric acid (SSA) is presented as an efficient heterogeneous catalyst under mild and solvent-free cond
- Habibi, Davood,Rahmani, Payam,Akbaripanah, Ziba
-
p. 417 - 421
(2014/01/06)
-
- NOVEL COMPOUND HAVING SKIN-WHITENING, ANTI-OXIDIZING AND PPAR ACTIVITIES AND MEDICAL USE THEREFOR
-
Provided are a novel compound having skin-whitening, anti-oxidizing and PPAR activities and a medical use thereof, and the compound has skin-whitening activities for the suppression of tyrosinase, and accordingly, is useful for use in skin-whitening pharmaceutical composition or cosmetic products; has anti-oxidant activities, and accordingly, is useful for the prevention and treatment of skin-aging; and has PPAR activities, and in particular, PPARα and PPARγ activities, and accordingly, is useful for use in pharmaceutical compositions or health foods which are effective for the prevention and treatment of obesity, metabolic disease, or cardiovascular disease.
- -
-
Paragraph 0250-0252
(2014/02/16)
-
- 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)
-
- Highly efficient and chemoselective method for the thioacetalization of aldehydes and transthioacetalization of acetals and acylals catalyzed by H 2SO4-silica under solvent-free conditions
-
Chemoselective and efficient thioacetalization of a variety of aldehydes was achieved in excellent yields at room temperature using 1,2-ethanedithiol in the presence of catalytic amounts of H2SO4-silica. Thioacetals were also prepare
- Pourmousavi, Seied Ali,Kazemi, Shaghayegh Sadat
-
experimental part
p. 917 - 923
(2012/07/16)
-
- 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)
-
- 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)
-
- An efficient method for the transthioacetalization of acylals and acetals under mild conditions
-
A rapid and efficient method for the transthioacetalization of acylals (1,1-diacetates) and acyclic and cyclic acetals is described. The reaction was carried out using 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane tribromide (1 mol%). The yield of the transthioacetalization was high and reaction conditions involve the use of acetonitrile as the solvent at room temperature; isolation is simple and the products are nearly pure.
- Pourmousavi, Seied Ali,Hadavankhani, Majid,Zinati, Zahra
-
experimental part
p. S495-S501
(2012/05/31)
-
- 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)
-
- 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)
-
- 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)
-
- Organocatalytic methods for chemoselective O-tert-butoxycarbonylation of phenols and their regeneration from the O-t-Boc derivatives
-
(Chemical Equation Presented) Carbon tetrabromide (CBr4) catalyzes O-tert-butoxycarbonylation of functionalized phenols without any side reactions (bromination, addition of CBr3 to a double bond, and formation of symmetrical diaryl carbonates, cyclic carbonates, or carbonic-carbonic anhydrides). The parent phenols are regenerated from the O-t-Boc derivatives by the catalyst system CBr4-PPh3 without affecting other protecting groups (aryl alkyl ether, alkyl ester, and thioacetal) or competitive side reaction such as bromination, nitrene (from NO2) and α,α-dibromoolefine (with CHO/COMe) formation, and transesterification (with CO2Me/Et) taking place.
- Chankeshwara, Sunay V.,Chebolu, Rajesh,Chakraborti, Asit K.
-
supporting information; scheme or table
p. 8615 - 8618
(2009/04/11)
-
- An efficient method for thioacetalization of carbonyl compounds in the presence of a catalytic amount of benzyltriphenylphosphonium tribromide under solvent-free conditions
-
A variety of carbonyl compounds have been successfully converted to the corresponding thioacetal derivatives in good to excellent yields on the reaction of carbonyl compounds with 1,2-ethanedithiole, 1,3-propanedithiol, and ethanethiol in the presence of
- Hajipour, Abdol R.,Pourmousavi, Seied A.,Ruoho, Arnold E.
-
p. 921 - 937
(2008/02/05)
-
- Perchloric acid adsorbed on silica gel (HClO4-SiO2) as an extremely efficient and reusable catalyst for 1,3-dithiolane/dithiane formation
-
Perchloric acid adsorbed on silica gel (HClO4-SiO2) has been found to be an extremely efficient and reusable catalyst for 1,3-dithiolane and 1,3-dithiane formation under solvent-free conditions at room temperature. Georg Thieme Verla
- Rudrawar, Santosh,Besra, Ram C.,Chakraborti, Asit K.
-
p. 2767 - 2771
(2008/02/05)
-
- A rapid and efficient method for 1,3-dithiolane synthesis
-
A mild, efficient and solvent-free protocol for conversion of aldehydes and ketones into their corresponding 1,3-dithiolanes using 1,2-ethanedithiol in the presence of a catalytic amount of SnCl2·2H2O is reported.
- Bez, Ghanashyam,Gogoi, Dipankoj
-
p. 5155 - 5157
(2007/10/03)
-
- Tetrahydropyranylation and depyranylation of alcohols catalyzed by aqueous zinc tetrafluoroborate
-
Aqueous solution of zinc tetrafluoroborate as an effective catalyst for tetrahydropyranylation and depyranylation of alcohols has been described. Copyright Taylor & Francis, Inc.
- Islam, Samimul,Majee, Adinath,Khan
-
p. 1789 - 1793
(2007/10/03)
-
- Copper(II) tetrafluoroborate as an extremely efficient catalyst for 1,3-dithiolane/dithiane formation from carbonyl compounds under solvent-free conditions at room temperature
-
Copper(II) tetrafluoroborate hydrate is a new and extremely efficient catalyst for 1,3-dithiolane/dithiane formation from aromatic, heteroaromatic and aliphatic aldehydes and cyclic saturated ketones in 1-5 min under solvent-free conditions at room temper
- Besra, Ram C.,Rudrawar, Santosh,Chakraborti, Asit K.
-
p. 6213 - 6217
(2007/10/03)
-
- A simple and efficient heterogeneous procedure for thioacetalization of aldehydes and ketones
-
A new procedure for the protection of aldehydes and ketones as thioacetals promoted by catalytic amount of p-toluene-sulfonic acid and silica gel has been developed. This procedure offers versatility, short reaction time, excellent yield, good selectivity
- Ali, Mohammed Hashmat,Gomes, Maria Goretti
-
p. 1326 - 1332
(2007/10/03)
-
- Ruthenium(III) chloride-catalyzed thioacetalization of carbonyl compounds: Scope, selectivity, and limitations
-
A variety of carbonyl compounds can be easily and rapidly converted to the corresponding cyclic and acylic dithioacetals in the presence of a catalytic amount of ruthenium chloride in acetonitrile at room temperature. Some of the major advantages of this
- De, Surya Kanta
-
p. 673 - 676
(2007/10/03)
-
- Chemoselective thioacetalisation and transthioacetalisation of carbonyl compounds catalysed by tetrabutylammonium tribromide (TBATB)
-
Thioacetals and thioketals of various aldehydes and ketones were obtained directly from carbonyl compounds or by a transthioacetalisation process from cyclic O,O-acetals in the presence of dithiols and a catalytic amount of tetrabutylammonium tribromide (TBATB). Chemoselective thioacetalisation of aromatic aldehydes containing an electron-donating group in the presence of an aldehyde containing an electron-withdrawing group, aldehydes in the presence of ketones, aliphatic cyclic ketones in the presence of aromatic ketones and less hindered ketones in the presence of more hindered ketones have been achieved. A cyclic acetal containing an electron-donating group has been chemoselectively transthioacetalised in the presence of an acetal having an electron-withdrawing substituent. These selectivities are due to the intrinsic reactivity of the substrate themselves and are independent of the catalyst and reaction conditions, Shorter reaction times, mild reaction conditions, stability of acid sensitive protecting groups, high efficiencies, facile isolation of the desired products and the catalytic nature of the reagent are the attractive features of the present method.
- Naik, Sarala,Gopinath, Rangam,Goswami, Mousumi,Patel, Bhisma K.
-
p. 1670 - 1677
(2007/10/03)
-
- Selective thioacetalization of aldehydes catalyzed by aqueous zinc tetrafluoroborate
-
A wide range of cyclic dithioacetals are prepared from the corresponding aldehydes in the presence of aqueous solution of zinc tetrafluoroborate.
- Islam, Samimul,Majee, Adinath,Mandal, Tanmay,Khan
-
p. 2911 - 2916
(2007/10/03)
-
- Scandium Chloride-Catalyzed Chemoselective Thioacetalization of Aldehydes
-
A wide variety of acyclic and cyclic dithioacetals can be prepared chemoselectively from the corresponding aldehydes by employing a catalytic amount of scandium chloride in acetonitrile at room temperature.
- De, Surya Kanta
-
p. 828 - 830
(2007/10/03)
-
- Pr(OTf)3 as an efficient and recyclable catalyst for chemoselective thioacetalization of aldehydes
-
Praseodymium triflate has been found to be an efficient and recyclable catalyst for chemoselective protection of aldehydes.
- De, Surya Kanta
-
p. 2837 - 2840
(2007/10/03)
-
- Promotion of 1,3-Dithiolanes using a Bentonitic Clay as Catalyst
-
The reactions between 1,2-ethandithiol with several carbonylic compounds to form the corresponding 1,3-dithiolanes were performed using a natural clay as promotor. The target molecules are used as reagents to obtain fine chemicals, herbicides, fungicides,
- Aceves,Arroyo,Vargas,Miranda,Cabrera,Delgado
-
-
- A Highly Efficient and Chemoselective Synthetic Protocol for Tetrahydropyranylation/Depyranylation of Alcohols and Phenols
-
Various alcohols and phenols can be converted efficiently to the corresponding tetrahydropyranyl (THP) ethers in good yields using catalytic amounts of bromodimethylsulfonium bromide (0.005-0.02 equivalent) at room temperature. On the other hand, various THP ethers can also be deprotected to the parent alcoholic or phenolic compounds in CH2Cl2/ MeOH (5:2) by employing 0.05 equivalent of the same catalyst. Some of the major advantages of this procedure are its mild conditions, that it is highly selective and efficient, high yielding, and cost-effective, that it needs no solvent and is compatible with the presence of other protecting groups. Furthermore, no brominations occur at a double or triple bond, at an allylic position or even at an aromatic ring. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Khan, Abu T.,Mondal, Ejabul,Borah, Ballav M.,Ghosh, Subrata
-
p. 4113 - 4117
(2007/10/03)
-
- Nickel(II) chloride as an efficient and useful catalyst for chemoselective thioacetalization of aldehydes
-
A wide variety of acyclic and cyclic dithioacetals can be prepared chemoselectively from the corresponding aldehydes by employing a catalytic amount of nickel(II) chloride in dry CH2Cl2-MeOH (5:1) at room temperature in good yields.
- Khan, Abu T.,Mondal, Ejabul,Sahu, Priti R.,Islam, Samimul
-
p. 919 - 922
(2007/10/03)
-
- Indium triflate: A mild Lewis acid catalyst for thioacetalization and transthioacetalization
-
Protection of a variety of carbonyl compounds as thioacetals using indium triflate, a mild Lewis acid catalyst, was achieved at ambient temperature in very good yield. Transthioacetalization of oxyacetals into thioacetals was also achieved in an excellent
- Muthusamy, Sengodagounder,Arulananda Babu, Srinivasarao,Gunanathan, Chidambaram
-
p. 7897 - 7901
(2007/10/03)
-
- Facile and selective deprotection of aryl acetates using sodium perborate under mild and neutral conditions
-
A variety of aryl acetates are cleaved to the corresponding phenols using sodium perborate in methanol under mild conditions (25°C). The effectiveness of this protocol is manifested in its tolerance of different functional groups and selectivity of deprotection towards aryl acetates whereas alkyl acetates are found to be unreactive under these reaction conditions.
- Bandgar, Babasaheb P.,Uppalla, Lavkumar S.,Sadavarte, Vaibhav S.,Patil, Suresh V.
-
p. 1273 - 1276
(2007/10/03)
-
- Indium(III) chloride as an efficient, convenient catalyst for thioacetalization and its chemoselectivity
-
An efficient method for the preparation of 1,3-dithiolanes from aldehydes and ketones with 1,2-ethanedithiol in the presence of a catalytic amount of anhydrous indium(III) chloride is reported. A mild and highly chemoselective thioacetalization of carbony
- Muthusamy, Sengodagounder,Babu, Srinivasarao Arulananda,Gunanathan, Chidambaram
-
p. 359 - 362
(2007/10/03)
-
- A rapid and efficient method of thioacetalization of carbonyl compounds catalysed by POCl3-montmorillnite
-
Aldehydes and ketones were thioactalized with 1,2-ethanedithiol in the presence POCl3-montmorillonite at room temperature in excellent yields.
- Jin,Sun,Ma,Li
-
p. 1669 - 1673
(2007/10/03)
-
- Selective Catalytic Transesterification, Transthiolesterification, and Protection of Carbonyl Compounds over Natural Kaolinitic Clay
-
Transesterification and transthiolesterification of β-keto esters with variety of alcohols and thiols and selective protection of carbonyl functions with various protecting groups catalyzed by natural kaolinitic clay are described. The clay has been found to be an efficient catalyst in transesterifying long chain alcohols, unsaturated alcohols, and phenols to give their corresponding β-keto esters in high yields. For the first time, transthiolesterification of β-keto esters with a variety of thiols has been achieved under catalytic conditions. Clay also catalyzes selective transesterification of β-keto esters by primary alcohols in the presence of secondary and tertiary alcohols giving corresponding β-keto esters. A systematic study involving the reactivity of different nucleophiles (alcohols, amines, and thiols) toward β-keto esters is also described. Sterically hindered carbonyl groups as well as α,β-unsaturated carbonyl groups underwent protection without the deconjugation of the double bond. Chemoselective protection of aldehydes in the presence of ketones has also been achieved over natural kaolinitic clay.
- Ponde, Datta E.,Deshpande, Vishnu H.,Bulbule, Vivek J.,Sudalai, Ammugam,Gajare, Anil S.
-
p. 1058 - 1063
(2007/10/03)
-
- Natural kaolinitic clay: A remarkable reusable solid catalyst for the selective functional protection of aldehydes and ketones
-
Natural kaolinitic clay possessing transition metals such as Fe and Ti in its lattice has been found to catalyze efficiently the chemoselective acetalization and thioacetalization of variety of carbonyl compounds with ethane - 1,2 - diol and ethane - 1,2 - dithiol respectively.
- Ponde, Datta,Borate,Sudalai,Ravindranathan,Deshpande
-
p. 4605 - 4608
(2007/10/03)
-
- Selective Protection of Carbonyl Compounds. Silica Gel Treated with Thionyl Chloride as an Effective Catalyst for Thioacetalization
-
Silica gel treated with thionyl chloride was found to be an effective as well as highly selective catalyst for thioacetalization of aldehydes.With the use of this catalyst 1,3-dithioranes and 1,3-dithianes were obtained in excellent yields from various aldehydes.Under the same conditions ketones were similarly but more slowly thioketalized.This difference in reactivity between aldehydes and ketones was successfully utilized for the thioacetalization of aldehydes in the presence of ketones and also for the chemoselective conversion of keto aldehydes into the corresponding dithioacetals with the keto group remaining intact.
- Kamitori, Yasuhiro,Hojo, Masaru,Masuda, Ryoichi,Kimura, Tadashi,Yoshida, Tatsushi
-
p. 1427 - 1431
(2007/10/02)
-
- Comparative radioprotective activity of various pentagonal compounds with two heteroatomes
-
Various heterocyclic compounds with two heteroatomes were synthesized and their potential radioprotective activity was tested. This study shows the interest of phenylthiazolidines derivatives in chemical radioprotection.
- Robbe,Fernandez,Dubief,et al.
-
p. 235 - 243
(2007/10/02)
-