Reacciones de trifluorometilación catalizadas por metales de transición

Las reacciones de trifluorometilación tienen gran importancia en la industria farmacéutica por las propiedades que confieren a los compuestos que presentan tal grupo funcional. Este tipo de reacciones están presentes en la elaboración de sintones o unidades estructurales claves para la producción de Aprepitant, Fluoxetina, Leflunomida y Dutasterida, teniendo gran impacto en la industria farmacéutica. Se resumen los diferentes reactivos empleados en la trifluorometilación remarcando la relevancia que tienen las reacciones catalizadas por metales de transición en la obtención de procesos más baratos y limpios. DOI: https://doi.org/10.54167/tecnociencia.v16i1.83

Thickness and Thermal Conductivities of the Walls and Fluid Layer Effects on the Onset of Thermal Convection in a Horizontal Fluid Layer Heated from Below

The thermal boundary conditions have important effects on the hydrodynamics of a thermo‐convective fluid layer. These effects are introduced through the Biot number under the Robin type boundary conditions. The thermal conductivity and thicknesses of the walls are key properties to bridge two known ideal situations widely studied: the fluid layer bounded by two insulating walls and the fluid layer bounded by two perfect thermal conducting walls. This chapter is devoted to the physical mechanisms involved in the thermal boundary conditions, its influence on the linear stability of the fluid layer and its implications with the pattern formation. A review of very important investigations on the subject is also given. The role of the thermal conductivities and thicknesses of the walls is explained with help of curves of criticality for the thermoconvection in a horizontal Newtonian fluid layer