نتایج جستجو برای: solid acid

تعداد نتایج: 921902  

Ali Reza Kiasat Mehdi Fallah-Mehrjardi,

Silica sulfuric acid is employed as solid acid catalyst for the clean and less hazardousprotection of carbonyl compounds as 2,4-dinitrophenylhydrazone under solvent-free conditions.

Phosphosulfonic acid as a multi solid site was easilyprepared from the reaction of ammonium dihydrogen phosphatewith chlorosulfonic acid in CCl4and for improved its catalyticactivity was supported nano Silica was extracted from husk ricecontains about 95% of Silica the size of extracted nano silica wasdetermined by SEM efficiency of this solid acid in four componentcondensation reaction of arom...

Journal: :organic chemistry research 0
zahra kordrostami interest

in this work, so3h-functionalizedphthalimide (sfp) as a so3h-containing solid acid is prepared by the reaction of phthalimide with chlorosulfonic acid, and characterized by ft-ir, 1h and 13c nmr, mass, tg, dtg, xrd and sem. then, it is utilized as a highly efficient, heterogeneous and green catalyst for the one-pot multi-component condensation of dimedone with arylaldehydes, β-ketoesters and am...

AliReza Kiasat Raziye Najafi Birgani,

Phosphosulfonic  acid  as a  multi  solid site  was  easily  prepared  from  the reaction of ammonium  dihydrogen phosphate with chlorosulfonic acid in CCl4and for improved  its  catalytic activity  was  supported  nano Silica was  extracted from  husk  rice  contains  about 95%  of  Silica the  size of  extracted nano silica was  determined  by  SEM  efficiency of  this solid acid in four comp...

Two highly efficient protocols for the production of bis-coumarins under solvent-free conditions have been introduced. The reaction of 4-hydroxycoumarin (2 eq.) with arylaldehydes (1 eq.) using phthalimide-N-sulfonic acid (PhtSA) or isatin-N-sulfonic acid (IsSA), as solid-acid catalysts, afforded the mentioned compounds with good to excellent yields in short times.Briefly, we have introduced tw...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2011
ghodsi mohammadi ziarani alireza badiei masoomeh azizi peshman zarabadi

3,4-ِdihydropyrano[c]chromene derivatives were synthesized using sulfonic acid functionalized silica (sio2-pr-so3h) as a highly efficient heterogenous solid acid catalyst via one-pot three-component condensation of aromatic aldehydes with malononitrile and 4-hydroxycoumarin in excellent yields.

Journal: :iranian journal of catalysis 2014
bibi fatemeh mirjalili abdolhamid bamoniri fahimeh kalantari

[b(oh)3]0.78[b(oh)2(oso3h)]0.22 or (bsa) was simply prepared by addition of chlorosulfonic acid to commercial boric acid at room temperature. this cheap and green solid acid was used as an efficient catalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature.

Journal: :جنگل و فرآورده های چوب 0
داود افهامی سیسی دانشجوی دکتری چوب شناسی و صنایع چوب، دانشگاه تهران، ایران و دانشگاه مونپولیه، فرانسه یحیی همزه استاد گروه علوم و صنایع چوب و کاغذ دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران ماری فرانس تونن استاد مؤسسة تحقیقات سیراد، مونپولیه، فرانسه علی نقی کریمی استاد گروه علوم و صنایع چوب و کاغذ دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران آنتونیو پیزی استاد مؤسسة انستیب، دانشگاه نانسی، اپینال، نانسی، فرانسه کامبیز پورطهماسی دانشیار گروه علوم و صنایع چوب و کاغذ دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران

quebracho tannin wood adhesive in non formaldehyde approach has low autocondensation rate and needs more press time than formaldehyde-based wood adhesives to produce wood composites. in this study, boric acid was used to increase autocondensation rate of quebracho tannin adhesive to make poplar plywood. the main ingredients of the adhesives include quebracho tannin, naoh, hexamine, boric acid a...

Journal: :nanochemistry research 2016
sadegh rostamnia* esmail doustkhah

sulfonic acid-based precursors (sap) play an important role in tailoring mesoporous silica’s and convert them to a solid acid catalyst with a bronsted-type nature. these kinds of solid acids contribute to sustainable and green chemistry by their heterogeneous, recyclable, and high efficiency features. therefore, knowing the properties and reactivity of saps can guide us to manufacture a sulfona...

[B(OH)3]0.78[B(OH)2(OSO3H)]0.22 or (BSA) was simply prepared by addition of chlorosulfonic acid to commercial boric acid at room temperature. This cheap and green solid acid was used as an efficient catalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature.

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