A facile and efficient synthetic route to polyhydroquinolines has been developed via four-component condensation reactions of aldehydes, dimedone, ethyl acetoacetate and ammonium acetate in the presence of p-toluenesulfonic acid (p-TSA) catalyst in ethanol at ambient temperature through Hantzsch reaction. Simple work-up procedure, environmentally friendly, inexpensive and non-toxic catalyst, sh...

1566-7367/$ see front matter Crown Copyright 2 doi:10.1016/j.catcom.2010.01.010 * Corresponding authors. Tel./fax: +86 (21)6425382 E-mail addresses: [email protected] (J. Ren), w Wang). A novel carbon-based solid-acid catalyst was simply prepared for the first time by the thermal treatment of p-toluenesulfonic acid (TsOH) with D-glucose at 180 C in a sealed autoclave and it was proved to ha...

In this study an improved process for the production of 5-Methyl-1,2,4-triazolo(3,4-b) benzothiazole fungicide (IV) is described. Firstly, (2-methylphenyl) thiourea (I), 2-amino- 4-methylbenzothiazole (II) and 2-hydrazino-4-methylbenzothiazole (III) as intermediates consequently were prepared. Then IV is synthesized by the reaction of III with formic acid in the presence of p-toluenesulfonic ac...

The reaction of P-diketones 1 with phenyl hydrazine afforded 5-aryl-3-(1- methyl-5-nitro-2-imidazoly1)-1-phenylpyrazole (2) and 3-aryl-5-(1-methyl-5- nitro-2-imidazoly1) -1-phenylpyrazole (3). The reaction of diketones (1) with urea in the presence of p-toluenesulfonic acid gave 4-(or 6-)aryl-6-(or 4-)(1-methyl- 5-nitro-2-imidazolyl)-1-(lH)pyrimidones (4). The structures of all compounds w...

We show that molecular catalysts for fuel-forming reactions can be immobilized on graphitic carbon electrode surfaces via noncovalent interactions. A pyrene-appended bipyridine ligand (P) serves as the linker between each complex and the surface. Immobilization of a rhodium proton-reduction catalyst, [Cp*Rh(P)Cl]Cl (1), and a rhenium CO2-reduction catalyst, Re(P)(CO)3Cl (2), afford electrocatal...

In this report, 1-butyl-3-methylimidazolium chloride ([C4C1im]Cl) is demonstrated to enhance the kinetics of acid-catalysed hydrolysis of 1,4-β-glucans in binary solvent mixtures. [C4C1im]Cl plays other roles in the reaction beyond acting as a solvent for cellulose, as currently accepted. In fact, the presence of the IL increases the Hammett acidity of the catalyst dissolved in the reaction med...

New Dicoumarols 2a-g efficiently synthesized employing p-TSA as a catalyst from the reaction of 4-hydroxycoumarin with aryl aldehydes in water. This method offers direct access to structurally diverse derivatives good yields (65-94%). Upon heating 3,3' -arylidenebis-4-hydroxycoumarins derivative acetic anhydride, epoxydicoumarins were formed. 1H, 13C{1H}-NMR, elemental analysis, and infrared sp...