Synthesis of Biginelli Compounds Using Cobalt Hydrogen Sulfate

Efficient synthesis of various 2‐oxo(thioxo)‐1,2,3,4‐tetrahydropyrimidines containing acetyl, carboethoxy, carbomethoxy and carboxamide groups on 5‐position of the N1‐substituted and N1‐unsubstituted heterocyclic ring was achieved using cobalt hydrogen sulfate Co(HSO₄)₂ under thermal conditions. Good to high yield, shorter reaction times, easy work up and simple preparation of Co(HSO₄)₂ are the advantages using this synthetic method.     

Approximation of fuzzy integrals using fuzzy bernstein polynomials

In this paper, we approximate the integration of continuous fuzzy real number valued function of one and two variables. To do this, we use Bernstein-type fuzzy polynomials. Moreover, we obtain the error estimates for these approximations in terms of the modulus of continuity.     

Experimental Investigation on Upgrading of Lignin‐Derived Bio‐Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst

Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al₂O₃, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H₂ + H₂S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H₂ consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the C_methyl–O bond is more facile than the scission of the C_aromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored.