We designed a ceria-vanadia/silica (Ce-V/SiO2) heterogeneous catalyst and used it for the green and efficient synthesis of 2-amino-3-cyano-4H-pyran derivatives. The green reaction was a multicomponent one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione, aromatic aldehyde, and malononitrile in an eco-compatible solvent (ethanol). The catalyst was synthesized and fully characterized by powd...

representation of the dimeric units of K2[Zr(SO4)3]. 2H20. Examination of this structure shows that breaking and remaking one oxygen bridge in each dimeric ring of K2[Zr(SO4)3.2H20 would result in the formation of infinite-Zr-O-SO -Zr-chains similar to those found in Na2[Zr(SO4)3]. 3H20 [Fig. 3(c)] and we see that in these two compounds we have an extension of the structural arrangements alread...

A procedure based on simulated annealing Monte Carlo (SAMC) was used to predict the crystal structures of hydrogen-bonded organic molecules that form molecular tapes. This procedure was optimized to select structures with good hydrogen-bond geometries; it allowed for deformations in molecular conformation due to packing pressures. Biasing the SAMC procedure to select structures with good hydrog...

Reactions among minerals and organic compounds in hydrothermal systems are critical components of the Earth's deep carbon cycle, provide energy for the deep biosphere, and may have implications for the origins of life. However, there is limited information as to how specific minerals influence the reactivity of organic compounds. Here we demonstrate mineral catalysis of the most fundamental com...

A highly efficient, simple and clean solvent-free protocol for the synthesis of polyhydroquinolines is described. The one-pot multi-component condensation reaction between arylaldehydes, dimedone (5,5-dimethylcyclohexane-1,3-dione), β-ketoesters and ammonium acetate in the presence of catalytic amount of (2.5 mol%) melamine trisulfonic acid (MTSA) as a recyclable, green and attractive sulfonic ...

An efficient and simple procedure for the synthesis of 1,8-dioxo-octahydroxanthenes from the aromatic aldehydes and 5,5-dimethylcyclohexane-1,3-dione (dimedone) in the presence of boric acid [BO3H3 or B(OH)3] as an inexpensive and reusable catalyst is described. The salient features of this methodology are: the elimination of corrosive liquid acids, high yields, simple methodology, short reacti...