Synthesis of 1,3-Diketones and β-Keto Thioesters via Soft Enolization

Ketones and thioesters undergo soft enolization and acylation using crude acid chlorides on treatment with MgBr2·OEt2 and i-Pr2NEt to give 1,3-diketones and β-keto thioesters, respectively. The acid chlorides are prepared from the corresponding carboxylic acids and used without purification in the carbon–carbon bond-forming step, thereby adding efficiency and cost reduction by avoiding the need to purify the acid chlorides and/or purchase them from a commercial source. Moreover, the process is conducted in a direct fashion that does not require prior enolate formation, which further enhances its efficiency and renders it very easy to carry out. The method is suitable for large scale applications.