Abstract
Reaction of dimethyloxosulfonium-(I), dimethylsulfonium-(II), and tetramethylenesulfonium benzoylmethylide (III) with 2, 2-diacetyl- and 2-acetyl-2-ethoxycarbonyl-1-ethoxyethylene (VI), in the presence of triethylamine afforded the corresponding 1-benzoyl-3, 3-diacetyl- and -3-acetyl-3-ethoxycarbonylallylides (VII, VIII, and IX) in a good yield. Similar treatment of ethoxycarbonylmethyldimethyl- and ethoxycarbonyltetramethylene sulfonium bromides (IV and V) with VI gave the corresponding allylides (X and XI). These 3, 3-diacetylallylides (VII and VIII) and 3-acetyl-3-ethoxycarbonylallylides (X) were hydrolyzed to the corresponding 3-acetylallylides (XII, XIII, and XIV) by treatment with dilute hydrochloric acid under a mild condition.
