21529-63-5

Upstream product

• 119-61-9 benzophenone 
• 204571-41-5 ethyl α,α-dibromocaproate 

Relevant academic research and scientific papers

Synthesis of Ynolates via Double Deprotonation of Nonbrominated Esters

Herein, we report a double deprotonation method used for the preparation of ynolates starting from nonbrominated 2,6-di-tert-butylphenyl esters. The current method is superior to the previously described double lithium/halogen exchange approach because easily accessible starting materials are used. This method will be especially useful for preparation of ynolates bearing functional groups in organic synthesis.

Stereoselective olefination of unfunctionalized ketones via ynolates

Ynolates react with ketones at room temperature to afford α,β,β,-trisubstituted acrylates (tetra-substituted 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 resulting β-lactone enolates. The stereoselectivity is determined in the ring-opening, which is regulated by torquoselectivity. In this paper, we describe the scope and limitations of olefination of ketones via ynolates and discuss the stereocontrol mechanism.

Practical synthesis of ynolate anions: Naphthalene-catalyzed reductive lithiation of α,α-dibromo esters

Reductive lithiation of α,α-dibromo esters using lithium naphthalenide afforded ester dianions leading to ynolate anions in good yields. Naphthalene-catalyzed reductive lithiation was also accomplished. This is a convenient, economical and practical method for the preparation of ynolate anions.