This study reports a new methodology for the efficient synthesis of trisphenol compounds using the reaction of 2,6-bis(hydroxymethyl) phenols with phenols under heterogeneous conditions. A sulfonated reduced graphene oxide (RGO-SO3H) nanocatalyst was used to promote the reaction under solvent-free conditions. A range of trisphenol compounds were produced in the presence of this catalyst system in good to excellent yields. In the presence of this catalyst system, a less amount of phenol is required, which improves the environment through its capability in synthesis of trisphenols. The RGO-SO3H catalyst was reusable at least for 8 times in this process without a significant decrease in its catalytic activity. پرونده مقاله

A series of copper and cobalt substituted nanospinel ferrites have been synthesized by the hydrothermal method. These compounds were characterized by FT-IR, XRD, EDX, SEM and VSM techniques. All of the synthesized nanospinel ferrites were found to be highly efficient and magnetically recoverable in the solvent-free synthesis of substituted 2,6-(2-hydroxybenzyl)-phenols (trisphenols). A wide range of trisphenols were successfully synthesized from the reaction of 2,6-bis (methylol) phenols (BMPs) and different substituted phenols in the presence of Cu0.5Co0.5Fe2O4 nanocatalyst. The best results were obtained in the presence of Cu0.5Co0.5Fe2O4 and molar ratios of phenol: BMP: catalyst, 3: 1: 0.1 under solvent-free conditions at 90°C. The catalyst could be easily separated using an external magnet. Comparison of the efficiency of Cu0.5Co0.5Fe2O4 with other reported catalytic systems showed that this catalyst has a higher activity for the synthesis of trisphenols. All the products were obtained in short reaction times and high yields. This could be related to the synergistic catalytic effect of copper and cobalt in the nanospinel on the activation of hydroxyl groups of BMPs. پرونده مقاله