Description

• General description: Formaldehyde diethyl acetal (FDEA, diethoxymethane, DEM) is a diethyl acetal. It has been synthesized from ethanol and aqueous formaldehyde.[1][2] It is a low boiling solvent useful for sodium hydride reactions, organolithium chemistry, copper-catalyzed conjugate additions and phase-transfer reactions. It is a potential alternate for tetrahydrofuran, dichloromethane, glyme and methylal. DEM is an ethoxymethylating agent, a formaldehyde equivalent and a carbonylation substrate.[3] Its condensation with 2-propylresorcinol to form resorcin[n]arenes (n=4–7) has been investigated.[4] The IR and Raman spectra[5] and conformations of DEM have been studied.[6] NMR spectroscopy has been used to study the aggregation behavior of organolithium compounds in diethoxymethane.[7] Unimolecular metastable decomposition of DEM upon electron impact has been studied.[8] Solubility of non-polar gases in DEM has been evaluated.[9]
• Application: Formaldehyde diethyl acetal may be used as a solvent in the esterification of carboxylic acids[10] and in the O-alkylation of a variety of phenols.[11]