60229-71-2Relevant academic research and scientific papers
Selective Synthesis of Acylated Cross-Benzoins from Acylals and Aldehydes via N-Heterocyclic Carbene Catalysis
Onodera, Kou,Suzuki, Yumiko,Takashima, Ryo
supporting information, p. 4197 - 4202 (2021/06/27)
The utility of acylals as building blocks for selective cross-benzoin synthesis was explored in this study. The synthesis of α-acetoxyketones (O-acyl cross-benzoins) was achieved via selective N-heterocyclic carbene-catalyzed cross-benzoin reactions using acylals as aldehyde equivalents. Thus, the combination of ortho-substituted phenyl acylals and aromatic/aliphatic aldehydes as coupling substrates using bicyclic triazolium salts as precatalysts and potassium carbonate as a base in THF at reflux temperature selectively yielded O-acyl cross-benzoins.
Acylation of Phenols, Alcohols, Thiols, Amines and Aldehydes Using Sulfonic Acid Functionalized Hyper-Cross-Linked Poly(2-naphthol) as a Solid Acid Catalyst
Kalla, Reddi Mohan Naidu,Reddy, Sirigireddy Sudharsan,Kim, Il
, p. 2696 - 2705 (2019/05/28)
Abstract: The hyper-cross-linked porous poly(2-naphthol) fabricated by the Friedel–Crafts alkylation of 2-naphthol has been functionalized with sulfonic acid to obtain a solid acid catalyst. The catalyst is applied for the protection of phenol, alcohols, thiols, amines and aldehydes with acetic anhydride at room temperature. The catalytic protection using the new solid acid is featured by achieving high yield at neat condition, needing no aqueous work-up and/or chromatographic separation, and showing excellent recycling efficiency, suggesting the potential of this sulfonated porous polymers as a new protection protocol in a wide range of sustainable chemical reactions. Graphical Abstract: [Figure not available: see fulltext.].
Tungstosulfonic acid as an efficient solid acid catalyst for acylal synthesis for the protection of the aldehydic carbonyl group
Kalla, Reddi Mohan Naidu,Kim, Mi Ri,Kim, Yu Na,Kim, Il
supporting information, p. 687 - 693 (2016/01/12)
Tungstosulfonic acid (TSA) has been found to be an efficient solid acid catalyst for the protection of aldehydic carbonyl groups by geminal diacetate (acylal) formation following the nucleophilic addition of acetic anhydride under neat conditions as well as in a solvent. The TSA catalyst is fully characterized by infrared spectroscopy, wide-angle X-ray scattering analysis, and scanning electron microscopy with energy dispersive X-ray spectroscopy. The deprotection of acylals to corresponding aldehydes has also been investigated under the similar conditions. The catalyst can be reused seven times without a significant loss of activity. In addition, no chromatographic separations are needed to obtain the desired products. This method is a green approach for the chemoselective protection of aldehydes in the presence of ketones.
Supported N-propylsulfamic acid onto Fe3O4 magnetic nanoparticles as a reusable and efficient nanocatalyst for the protection/deprotection of hydroxyl groups and protection of aldehydes
Rostami, Amin,Tahmasbi, Bahman,Abedi, Fatemeh
, p. 3689 - 3701 (2016/04/05)
N-propylsulfamic acid supported onto Fe3O4 magnetic nanoparticles (MNPs-PSA) as an efficient and magnetically reusable nanocatalyst has been reported for the tetrahydropyranylation/depyranylation of a wide variety of alcohols and phenols by changing the solvent medium. Also, the protection of aldehydes as acylals using Ac2O in the presence of catalytic amount MNPs-PSA in good to high yields at room temperature under solvent-free conditions is described. After completing the reaction, the catalyst was easily separated from the reaction mixture with the assistance of an external magnetic field and reused for several consecutive runs without significant loss of their catalytic efficiency.
Zinc zirconium phosphate as an efficient catalyst for chemoselective synthesis of 1,1-diacetates under solvent-free conditions
Hajipour, Abdol R,Karimi, Hirbod
, p. 1945 - 1955 (2015/12/30)
In the present study, a mild, rapid, and efficient method for the protection of aldehydes with acetic anhydride (AA) in the presence of zinc zirconium phosphate (ZPZn) as a nano catalyst, at room temperature is reported. Selective conversion of aldehydes was observed in the presence of ketones. Under these conditions, different aldehydes bearing electron-withdrawing and electron-donating substituents were reacted with AA and the corresponding 1,1-diacetates (acylals) were obtained in high to excellent yields. The steric and electronic properties of the different substrates had a significant influence on the reaction conditions. Also, the deprotection of 1,1-diacetates has been achieved using this catalyst in water. This nanocatalyst was characterized by several physico-chemical techniques. It was recovered easily from the reaction mixture, regenerated and reused at least 7 times without significant loss in catalytic activity. This protocol has the advantages of easy availability, stability, reusability of the eco-friendliness, chemoselectivity, simple experimental and work-up procedure, solvent-free conditions and usage of only a stoichiometric amount of AA.
Green procedures for the chemoselective synthesis of acylals and their cleavage promoted by recoverable sulfonic acid based nanoporous carbon (CMK-5-SO3H)
Zareyee, Daryoush,Mirzajanzadeh, Ehsan,Khalilzadeh, Mohammad Ali
, p. 1229 - 1234 (2015/10/06)
A selective synthesis of gem-diacetates from the reaction of aldehydes and acetic anhydride in the presence of recyclable nanoporous solid sulfonic acid (CMK-5-SO3H) under solvent-free reaction conditions is reported. The catalyst was also found to be highly active for deprotection of resulting acylals in water. [Figure not available: see fulltext.]
Phospho sulfonic acid as an efficient and recyclable solid acid catalyst for the solvent-free preparation of acylals
Kalla, Reddi Mohan Naidu,Park, Huiju,Hoang, Trinh Thi Kim,Kim, Il
supporting information, p. 5373 - 5376 (2015/01/09)
Phospho sulfonic acid (PSA) acts as a highly effective and reusable catalyst for the chemo-selective protection of aldehydes with acetic anhydride under solvent-free conditions. The desirable features of this new catalytic methodology include its sustaina
Chemoselective synthesis of geminal diacetates (acylals) using eco-friendly reusable propylsulfonic acid based nanosilica (SBA-15-Ph-PrSO3H) under solvent-free conditions
Zareyee, Daryoush,Moosavi, Sayed M.,Alaminezhad, Alireza
, p. 227 - 231 (2013/08/23)
An expeditious method for the acetylation of aldehydes by mesoporous solid sulfonic acid (SBA-15-Ph-PrSO3H) under solvent-free reaction conditions was described. The route furnished selectively and in excellent yields the corresponding 1,1-diacetates starting from aldehydes and acetic anhydride using the environmentally friendly catalyst. The catalyst was found to be highly active and selective and could be recycled several times.
Ultrasound assisted the chemoselective 1,1-diacetate protection and deprotection of aldehydes catalyzed by poly(4-vinylpyridinium)hydrogen sulfate salt as a eco-benign, efficient and reusable solid acid catalyst
Khaligh, Nader Ghaffari,Shirini, Farhad
, p. 19 - 25 (2013/01/15)
Poly(4-vinylpyridinium) hydrogen sulfate solid acid was found to be efficient catalyst for preparation of 1,1-diacetate using ultrasound irradiation at ambient temperature and neat condition. Deprotection of the resulting 1,1-diacetates were achieved using the same catalyst in methanol solvent under ultrasound irradiation at room temperature. This new method consistently has the advantage of excellent yields and short reaction times. Utilization of solvent free, simple reaction conditions, isolation, and purification makes this manipulation very interesting from an economic and environmental perspective. Further, the catalyst can be reused and recovered for several times.
A succinimide-N-sulfonic acid catalyst for acetylation reactions in absence of a solvent
Shirini, Farhad,Khaligh, Nader Ghaffari
, p. 695 - 703 (2013/08/25)
A small amount of succinimide-N-sulfonic acid efficiently catalyzed the acetylation of a variety alcohols, phenols, thiols, amines and aldehydes with acetic anhydride at room temperature under solvent free conditions. This catalyst has the advantages of excellent yields and short reaction times and the reaction can be carried out on a large scale, which makes it potentially useful for industrial applications.
