Estudo e aplicação de ácidos de Brönsted como catalisadores na reação de alilação de aldeídos por aliltrifluoroborato de potássio.

Abstract

The homoallylic alcohols are versatile synthetic intermediates in the preparation of biologically active molecules. These compounds can be easily obtained through allylation reaction of carbonyl compounds by allylic organometallic species. However, despite the numerous methodologies that described for allylic grouping adding a special stand at the allylation promoted by there-trifluoroborate salts, since these organoboron reagents are crystalline solids, can be stored for long periods, they are stable air and allow salts are the reactions are conducted in an aqueous medium. In this context, design features as a strategy to study the allylation reaction by- trifluoroborate there potassium promoted by different Brönsted acids in order to bring the homoallylic alcohols in good yields and in short periods of time. For this methodology will consist in the evaluation of the influence of various parameters on this synthesis, such as type and amount of Brönsted acid used, solvent system, temperature, type of energy and types of carbonyl compounds. In addition, the synthesized homoallylic alcohols have their structures characterized by the usual spectroscopic methods. As a result potassium Aliltrifluoroborato was obtained in 35% yield as a white crystalline solid. The salicylic acid proved to be the best catalyst for the allylation reaction. An efficient and environmentally friendly method using water as a main solvent and minor amounts of catalysts for the synthesis of homoallylic alcohols by aldehyde allylation of potassium aliltrifluoroborato has been developed to obtain excellent yield ranges from 60 to 94% and less reaction time at room temperature.