Tandem bis-aldol reaction of ketones: A facile one-pot synthesis of 1,3-dioxanes in aqueous medium

[GRAPHICS] A novel tandem bis-aldol reaction of ketone with paraformaldehyde catalyzed by polystyrenesulfonic acid in aqueous medium delivers 1,3-dioxanes in high yield. This one-pot, operationally simple microwave-assisted synthetic protocol proceeds efficiently in water in the absence of organic solvent, with excellent yield.