Arylation of diethyl malonate and ethyl cyanoacetate catalyzed by palladium/di-tert-butylneopentylphosphine. Issue 23 (3rd June 2015)

• Record Type: Journal Article
• Authors: Semmes, Jeffrey G.; Bevans, Stephanie L.; Mullins, C. Haddon; Shaughnessy, Kevin H.
• Is Part Of: Tetrahedron letters. Volume 56:Issue 23(2015)
• Page Start: 3447
• Page End: 3450
• Publication Date: 2015-06-03
• Subjects: Cross-coupling -- Palladium -- Phosphine -- Enolate; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2015.01.072
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: α-Arylated carbonyl derivatives are important structural motifs in many natural products and pharmaceutically active compounds. Although arylation of simple monocarbonyl compounds is a well-established methodology, metal-catalyzed arylation of β-dicarbonyl derivatives is significantly more challenging. The ability of β-dicarbonyl anions to bind to palladium in a κ 2 - O, O mode, rather than the κ 1 - C -bound mode required for bond formation, often results in the deactivation of catalyst systems. The C -bound form of the enolate can be favored through the use of sterically demanding ligands. Herein, we report that the sterically demanding di- tert -butylneopentylphosphine (DTBNpP) ligand in combination with Pd(dba)2 provides an effective catalyst for the coupling of aryl bromides and chlorides with diethyl malonate. The Pd/DTBNpP system also catalyzes the coupling of aryl bromides with ethyl cyanoacetate.