Ynolates react with ketones at room temperature to afford α, β, β-trisubstituted acrylates (tetrasubstituted olefins) with 2: 1-8: 1 geometrical selectivities. This can be regarded as a new olefination reaction of ketones giving tetrasubstituted olefins in good yield, even in the case of sterically hindered substrates. The reaction mechanism involves cycloaddition of ynolates with a carbonyl group and subsequent thermal electrocyclic ring-opening of the ...
