Chimica Organica: Hydroxycinnamyl Alcohols

A Facile Preparation of Hydroxycinnamyl Alcohols with Simultaneous Protection of Phenol Groups as Carbonate

Lucia Panzella, Marina DellaGreca, and Luigi Longobardo*[a]

A novel procedure for reduction and simultaneous protection of phenol groups of hydroxycinnamic acids to the related alcohols has been developed. During the formation of mixed anhydrides from the acids and an alkyl chloroformate, the phenol was protected as carbonate, and the mixed anhydrides were reduced with an aqueous solution of sodium borohydride. Free phenols were obtained by deprotection under mild conditions with 30% aq. NH4OH in methanol. O-protected phenolic alcohols can be converted by standard methods into orthogonally protected derivatives. This rapid and efficient synthetic method offers a simple and high-yield preparation of these important fine chemicals, overcoming the tedious and costly procedures associate with the use of strong reducing agents such as LiAlH4 and DIBALH.

ChemistrySelect 2018, 3, 10637 –10640