Dichloro and chloromethyl Ga(III) complexes of general formulae [XClGa-eta2-{R2P(E)NP(E'R'2-E,E'}](X = Cl, R, R'= Ph, E, E'= O (1), S (2), Se (3); R = Ph, R'= OEt, E = O, E'= S (4); R = Me, R'= Ph, E, E'= S (5) and X = Me, E, E'= O (6), S (7), Se (8)) were synthesised by either metathesis reactions between GaCl3 and the potassium salt of the ligand (X = Cl) or by methane eliminations from in situ prepared GaMe2Cl and the protonated ligands LH (X = Me). Redistribution reaction of (3) in either CDCl3 or THF afforded the solvent-free tetracoordinate gallium spirocycle cation [Ga-{eta2-{Ph2P(Se)NP(Se)Ph2-Se,Se'})2]+ (9+). The molecular structures of complexes 2, 4, 5, 7 and 9(+) show non-planar gallacycle rings.

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Organoaluminium(III) thioetherbis(phenolate) complexes derived from 2,2-thiobis(4,6-diterbuthylphenolate) (Stdiol) and 2,2-thiobis(4,6-dimethylphenolate) (Smdiol) were prepared by reaction of AlMe3 with the diol proligands LH2 (SmdiolH2, StdiolH2). Monomeric complexes of general formulae [LAlR(L)] (L = Stdiol, R = Me, L = THF (1); L = Stdiol, R = Me, L = Et2O (2); L = Stdiol, R = iBu, L = THF) (3); L = Smdiol, R = Me, L = THF (4); L = Smdiol, R = iBu, L = THF (5)) and [LAlCl(THF)] (L = Stdiol (6); L = Smdiol (7)) were obtained when the reactions were performed in THF or Et2O in hexane or toluene, species of formulae [(L2Al)AlR2] (L = Stdiol, R = Me (8); L = Stdiol, R = iBu (9); L = Smdiol, R = Me (10)) were formed as evidenced by spectroscopic methods. Crystals suitable for X-ray diffraction studies were obtained for 2, 3, 4, 6, 8, 9 and 10. In these cases the sulfur atom coordinates to the aluminium center with Al-S bond lengths between 2.43-2.75 A adopting boat-boat conformations. Compounds 1, 3, 4, and 8 were tested in the catalytic Diels-Alder cycloaddition reaction between methacrolein and cyclopentadiene showing excellent regioselectivities with good conversion yields.

Amination of allylic alcohols is facilitated via cooperative catalysis. Catalytic Ti(O- i-Pr) is shown to dramatically increase the rate of nickel-catalyzed allylic amination, and mechanistic experiments confirm activation of the allylic alcohol by titanium. Aminations of primary and secondary allylic alcohols are demonstrated with a variety of amine nucleophiles. Diene-containing substrates also cyclize onto the nickel allyl intermediate prior to amination, generating carbocyclic amine products. This tandem process is only achieved under our cooperative catalytic system.

In this study, multidisciplinary teams were formed to develop educational content as digital videos to help in the learning process in Science, Tech-nology, Engineering and Mathematics (STEM) education. The usefulness of the web-learning tool was evaluated by surveys and tests taken by chemical engineering freshman students. The results showed that these students’ scores were higher than the scores obtained by students of previous courses where the web-learning tool was not employed. On the other hand, the au-dience analysis indicated that the average age is 18-24 (91.2%) and the gen-der distribution was 54.9% male and 46.6% female from different countries (Mexico, Colombia, Spain, U.S., among others).

A través de calculos de primeros principios basados en la Teoria del Funcional de la Densidad (DFT) a nivel de la aproximación del gradiente generalizado GGA (el funcional Perdew-Burke-Ernzerhof, PBE) se investiga el mecanismo de adsorción de metanol en dos adsorbentes hidrofóbicos, ZIF-71 y ZIF-71(CIBr) a través del calculo de las energias de interacción en los sitios mas favorecidos en los adsorbentes. El estudio se realizó con el fragmento Zn-imidazolato y el metanol. La posición mas favorecida de la molécula de metanol hacia el adsorbente fue a través del grupo hidroxilo, lo cual genera una deformación de la molécula original debido a las interacciones de enlaces tipo puente de hidrógeno en los ligantes imidazolato del adsorbente. En la posición del alcohol a través del grupo metilo hacia el adsorbente, no se observa esta deformación en la molécula. Estas caracteristicas son relevantes para la adsorcién del metanol sobre la superficie del MOF donde la reorientacion de los ligantes esta impedida dada la rigidez de su red cristalina.

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