An Improvement for the Synthesis of Terminal Olefin from Carbonyl Compounds by Methylene Iodide and Magnesium Amalgam

Abstract

It has been reported by Cainelli that the reaction of benzaldehyde with methylene iodide and the amalgam of magnesium with mercury affords styrene. When a small amount of mercury was used for this reaction, the yield of styrene was remarkably increased (Fig.1). According to this method, following aldehydes and ketones gave the corresponding carbonyl-methylenated products in the yields given in the parentheses: p-methylbenzaldehyde (75 %), p-chlorobenzaldehyde (67 %), n-heptaldehyde (48 %), diethyl ketone (68 %), cyclohexanone (38 %).