LookChem

https://www.lookchem.com/CASDataBase_7440-38-2.htm The epitaxial lift-off process allows the separation of a thin layer of III/V material from the substrate by selective etching of an intermediate AlAs layer with HF In a theory proposed for this process, it was assumed that for every mole of AIAs dissolved three moles of H 2  gas are formed. In order to verify this assumption the reaction mechanism and stoichiometry were investigated in the present work. The solid, solution and gaseous reaction products of the etch process have been examined by a number of techniques, It was found that aluminum fluoride is formed, both in the solid form as well as in solution. Furthermore, instead of H 2  arsine (AsH 3 ) is formed in the etch process. Some oxygen-related arsenic compounds like AsO, AsOH, and AsO 2  have also been detected with gas chromatography/mass spectroscopy. The presence of oxygen in the etching environment accelerates the etching process, while a total absence of o...

https://www.lookchem.com/CASDataBase_17480-69-2.htm Several strategies for the development of the synthesis of P-chiral organophosphorus compounds with (L)-prolinol as a source of chirality have been examined. A reaction of L-prolinol with a set of different alkyl/arylphosphonous acid diamides led in most of the cases to the quantitative formation of the appropriate bicyclic oxazaphospholidines with complete diastereo and enantioselectivity. The latter were reacted with BH 3  complex and the formed borane analogues were submitted to structural modifications leading to tertiary phosphine-boranes. Additionally, the effectiveness of oxazaphospholidines as ligands in transition metal asymmetric catalysis has been tested in hydrogenation of dehydroaminoacid esters and imine. 

https://www.lookchem.com/CASDataBase_7440-38-2.htm The epitaxial lift-off process allows the separation of a thin layer of III/V material from the substrate by selective etching of an intermediate AlAs layer with HF In a theory proposed for this process, it was assumed that for every mole of AIAs dissolved three moles of H 2  gas are formed. In order to verify this assumption the reaction mechanism and stoichiometry were investigated in the present work. The solid, solution and gaseous reaction products of the etch process have been examined by a number of techniques, It was found that aluminum fluoride is formed, both in the solid form as well as in solution. Furthermore, instead of H 2  arsine (AsH 3 ) is formed in the etch process. Some oxygen-related arsenic compounds like AsO, AsOH, and AsO 2  have also been detected with gas chromatography/mass spectroscopy. The presence of oxygen in the etching environment accelerates the etching process, while a total absence of o...

https://www.lookchem.com/CASDataBase_100-64-1.htm o -Iodoxybenzoic acid (IBX) is confirmed as a powerful tool for the oxidation of hydroxylamines. The synthetic route is demonstrated as efficient and user friendly, and is exploited on various carbohydrate-derived N,N-disubstituted hydroxylamines (cyclic, acyclic, and functionalized ones), affording the corresponding nitrones in good yields and regioselectivity. N-Monosubstituted hydroxylamines revealed an interesting divergent behavior depending on the reaction conditions. While IBX oxidation in dimethyl sulfoxide at 45 °C furnished oximes as reported, the oxidation in dichloromethane at room temperature afforded efficiently the unusual corresponding nitroso dimers. 

https://www.lookchem.com/CASDataBase_73-22-3.htm Isotopologs are powerful tools for investigating biological systems. We report a biosynthetic-cascade synthesis of Trp isotopologs starting from indole, glycine, and formaldehyde using the enzymesl-threonine aldolase and an engineered β-subunit of tryptophan synthase. This modular route to Trp isotopologs is simple and inexpensive, enabling facile access to these compounds.

https://www.lookchem.com/CASDataBase_7439-95-4.htm A fine-grained AZ91 alloy was prepared by equal channel angular pressing (ECAP). The evolution of the microstructure and the deformation behavior were investigated as a function of the number of ECAP passes. At room temperature the tensile strength of the ECA pressed specimens is higher than that of the initial state due to the grain refinement and the increase of the dislocation density during ECAP. Above 200 °C the ductility increases due to the increase of the relative fraction of c + a dislocations and also owing to the breakage of the rod-like Al 12 Mg 17  precipitates during ECAP processing.