Enolic or readily enolizable carbonyl compounds undergo a-alkoxyallylation upon reaction with acetals of a,@-enals or ethoxyallene at temperatures ranging from 200 'C to ambient. Whereas reactions of the highly enolic or acidic carbonyl compounds (endocyclic 8- diketones, a-cyano ketones, a-nitro carbonyl compounds, and a-hydroxymethylene derivatives) occurred simply upon heating, alkylation of the less acidic exocyclic@- ...