A Mild, Efficient Protocol for the Synthesis of Homoallylic Alcohols Using Potassium Allyltrifluoroborate Promoted by Salicylic Acid

Background: In the current decade, organotrifluoroborates have attained remarkable development in Chemistry and Materials. This can be evidenced by the increasing number of articles, review articles and patents devoted to this subject. As a consequence, the number of citations derived from papers dealing with this subject has experienced an exponential growth in the last years. The aim of this paper to describe a methodology based on the use of potassium allyltrifluoroborate for the synthesis of homoallylic alcohols using water as a co-solvent and under mild reaction conditions. Methods: The methodology is very robust (wide range of aldehydes) and simple, it uses low catalyst loadings and it is synthetically useful because it could be applied for the synthesis of more complex compounds. In addition, detailed experimental procedures, including the preparation of the starting materials, as well as the corresponding 1H, 13C, 19F and 11B spectra for all synthesized compounds are provided. Results: The method is environmentally friendly while it uses water as a solvent and the desired compounds containing different functionalities were obtained in moderate to good yields (60-93%) without the need of further purification in a very chemo- and regioselective way. Conclusion: Salicylic acid can efficiently promote the allylation of aldehydes using potassium allyltrifluoroborate at room temperature to yield the corresponding homoallylic alcohols in moderate to good yields. The method is efficient and environmentally friendly while it uses water as co-solvent. In addition the method is regio- and chemoselective and could be applied in the synthesis of more complex homoallylic alcohols.