- Poly(4-vinylpyridinium) perchlorate as an efficient solid acid catalyst for the chemoselective preparation of 1,1-diacetates from aldehydes under solvent-free conditions
-
Poly(4-vinylpyridinium) perchlorate has been used as a supported, recyclable, environmentally-benign catalyst for the formation of acylals from aliphatic and aromatic aldehydes in good to excellent yields under solvent-free conditions. Notably, the reaction conditions were tolerant of ketones. This methodology offers several distinct advantages, including its operational simplicity and high product yield, as well as being green in terms of avoiding the use of toxic catalysts and solvents. Furthermore, the catalyst can be recovered and reused several times without any loss in its activity.
- Khaligh, Nader Ghaffari
-
p. 329 - 334
(2014/04/03)
-
- 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
-
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.
- Khaligh, Nader Ghaffari,Shirini, Farhad
-
-
- A succinimide-N-sulfonic acid catalyst for acetylation reactions in absence of a solvent
-
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.
- Shirini, Farhad,Khaligh, Nader Ghaffari
-
p. 695 - 703
(2013/08/25)
-
- Rice husk supported FeCl3 nanoparticles as an efficient and reusable catalyst for the chemoselective 1,1-diacetate protection and deprotection of aldehydes
-
1,1-Diacetates were produced from a variety of aromatic aldehydes using rice husk supported FeCl3 nanoparticles as a catalyst. The procedure generally resulted in good yields (98%) of aromatic aldehydes including those carrying electron donating- or withdrawing-substituents. Deprotection of the resulting 1,1-diacetates was also achieved using the same catalyst in ethanol. This new method consistently has the advantages of excellent yields and relatively short reaction times. Further, the catalyst can be reused and recovered for several times.
- Shirini, Farhad,Akbari-Dadamahaleh, Somayeh,Mohammad-Khah, Ali
-
-
- Introduction of N-sulfonic acid poly(4-vinylpyridinum) chloride as an efficient and reusable catalyst for the chemoselective 1,1-diacetate protection and deprotection of aldehydes
-
N-sulfonic acid poly(4-vinylpyridinium) chloride is easily prepared by the reaction of poly(4-vinylpyridine) with neat chlorosulfonic acid. This reagent can be used as an efficient catalyst for the preparation of 1,1-diacetates at room temperature and neat condition. Deprotection of the resulting 1,1-diacetates can also be achieved using the same catalyst in methanol. This new method consistently has the advantages of excellent yields and short reaction times. Further, the catalyst can be reused and recovered for several times.
- Shirini, Farhad,Jolodar, Omid Goli
-
experimental part
p. 61 - 69
(2012/04/17)
-
- Preparation of silica-bonded propyl-diethylene-triamine-N-sulfamic acid as a recyclable catalyst for chemoselective synthesis of 1,1-diacetates
-
A simple and efficient procedure for the preparation of silica-bonded propyl-diethylene-triamine-N-sulfamic acid (SPDTSA) by reaction of 3-diethylenetriamine-propylsilica (DTPS) and chlorosulfonic acid in chloroform is described. Silica-bonded propyl-diethylene-triamine-N-sulfamic acid is employed as a recyclable catalyst for the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature. Catalyst could be recycled for several times without any additional treatment.
- Nouri Sefat, Maryam,Deris, Abdolah,Niknam, Khodabakhsh
-
experimental part
p. 2361 - 2367
(2012/02/03)
-
- Silica-bonded S-sulfonic acid as a recyclable catalyst for chemoselective synthesis of 1,1-diacetates
-
A simple and efficient procedure for the preparation of silica-bonded S-sulfonic acid (SBSSA) by reaction of 3-mercaptopropylsilica (MPS) and chlorosulfonic acid in chloroform is described. This solid acid is employed as a recyclable catalyst for the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature.
- Niknam, Khodabakhsh,Saberi, Dariush,Sefat, Maryam Nouri
-
scheme or table
p. 4058 - 4062
(2009/10/11)
-
- Pharmaceutical compositions
-
Pharmaceutical compositions which are useful for the treatment of cancer or illnesses which arise due to an abnormally elevated cell proliferation comprise acyl derivatives of aromatic aldehydes, especially arylidene diesters and α-alkoxyarylidene esters of general formula (I). STR1
- -
-
-