Silica Sulphuric Acid: An Efficient and Recyclable Catalyst for the Synthesis of β‐Acetamido Ketones in Single Pot

NaHSO4•H2O as an efficient and eco-friendly catalyst for the one-pot multicomponent synthesis of β-acetamido ketones under mild and heterogeneous conditions

“…It is interesting to mention that the OH group in the product was obtained as acylated group (Table 1, entry 11). Although it is not clear how sodium hydrogen sulfate acts as a catalyst for the reaction, on the basis of previously reported mechanism, 12,13 it is suggested that the aldehyde is first acylated (in the presence of enol form of acetophenone derivative) to an intermediate (I) which then reacts with the acetonitrile to produce the desired β-acetamido ketone. In summary, we have demonstrated sodium hydrogen sulfate as a cheap, commercially available, reusable and non-corrosive catalyst for the synthesis of β-acetamido ketones in excellent yields under mild reaction conditions.…”

“…Recently, other synthetic methods have been used for the formation of β-acetamido ketones through the multicomponent condensation of aryl aldehydes, enolizable ketones and acetyl chloride in acetonitrile in the presence of Lewis or Brǿnsted acid catalysts such as sulfuric acid absorbed on silica gel, 12,13 [21][22][23][24] Nafion-H, 25 and sulfated zirconia. 26 In recent years, sodium hydrogen sulfate has gained much interest in the synthesis of octahydroxanthenes, 27 protection and deprotection, [28][29][30][31][32][33][34][35][36] nitration, 37,38 nitrosation, 39 oxidation, [40][41][42] synthesis of halide derivatives, 43,44 coupling of indoles 45 and synthesis of quinazolinones.…”

Efficient Heterogeneous Catalytic One-Pot, Three Component Synthesis of γ-Hydroxy-β-Ketoamides

“…The best known route for the synthesis of this class of compounds is the Dakin-West reaction (9a) ,which involves the condensation of an amino acid with acetic anhydride in the presence of a base (9b) . Recently, other synthetic methods have been used for the formation of β-acetamidoketones through the multicomponent condensation of aryl aldehydes, enolizable ketones, and acyl chlorides in acetonitrile in the presence of Lewis or Brønsted acid catalysts such as CoCl 2 (10,11) , montmorillonite K-10 clay (12) , silica sulfuric acid (13) , BiCl 3 generated from BiOCl (14) , ZrOCl 2 .8H 2 O (15) , heteropoly acid (16) , sulfuric acid T absorbed on silica gel (17) , Sc(OTf) 3 (18) , silica supported H 3 PW 12 O 4 (19) , Fe(HSO 4 ) 3 (20) , Nafion-H (21) , NaHSO 4 .H 2 O (22) , and iron(III) chloride (23) , HAPs (24), ClSO 3 H (25) , cyl chlorides (26) . Despite these valuable protocols, these methods lack the generality to produce arrays of β-amido ketones.…”

Perfluorinated resin-sulfonic acid (Nafion-H): an efficient, environment friendly and recyclable heterogeneous catalyst for the one-pot multicomponent synthesis of β-acetamido ketones

“…5,6 Synthetic strategies based on one-pot multicomponent reactions overriding the conventional linear type synthesis and considered as powerful tools in the modern drug discovery process. 7 Earlier reports on the synthesis of β-acetamido ketones through multi component reactions is mainly using catalysts like CoCl 2 , 8 montmorillonite K10 clay, 9 BiCl 3 , 10 silica sulphuric acid, 11,12 and solid acid Hβ-zeolite. 13 The interest is continuously growing in recent years on the use of eco-friendly and recyclable catalysts due to environmental legislations.…”