Preparation of Acrylophenones and 2-Alkyl Indanones Utilizing Hexamethylenetetramine as an Inexpensive Mannich Reagent.

Abstract
Hexamethylenetetramine/acetic anhydride-promoted α-methylenation of aryl alkyl ketones followed by acid-catalyzed cyclization of the resulting acrylophenones produce 2-alkyl indanones in excellent yields.