Palladium‐Catalyzed Oxidative sp² CH Bond Acylation with Aldehydes

Abstract

An efficient method was developed for the direct acylation of arene sp 2 C À H bonds with aldehydes using palladium acetate as catalyst and peroxide as oxidant. The solvent-free oxidative acylation reaction assisted by a pyridine directing group provides an easy access to aromatic, aliphatic, and optical active ketones.

Transition-Metal-Catalyzed C–H Bond Addition to Carbonyls, Imines, and Related Polarized π Bonds

“…In 2010, Li and co-workers were able to expand the scope of this transformation to include Pd-catalyzed oxidative C–H acylation with alkyl aldehydes with the reaction conducted under neat conditions and employed tert -butyl hydroperoxide (TBHP) as oxidant. 21 …”

Palladium‐Catalyzed Oxidative Acylation of N‐Benzyltriflamides with Aldehydes via CH Bond Activation

“…[2] Since the pioneering discovery of C À H bond activation by Murai, [3] recent progress has been focused on dehydrogenative cross-coupling between sp 2 or sp 3 C À H bonds and sp 2 C À H bonds of arenes or alkenes. [13] Later, palladium-catalyzed sp 2 C À H bond acylations of 2-arylpyridines, [14] oxime, [15] acetanilides, [16] and indole [17] with aldehydes or alcohols were described. Although the reactions using arenes or alkenes as coupling partners have been well documented, the reactions between the aromatic sp 2 C À H bond and aldehydes remain relatively unexplored.…”

Acylation of (Hetero)Arenes through CH Activation with Aroyl Surrogates

“…However, alkyl aldehydes were not converted. In 2010, Li and co‐workers reported that both aromatic and aliphatic aldehydes could be successfully applied by using tert ‐butyl hydroperoxide (TBHP; 5 M in decane) as the oxidant under neat conditions (Scheme ) 4b. No desired product was obtained in the model system when [Ru 3 CO 12 ] or [Rh(cod)Cl] (cod=1,5‐cyclooctadiene) was applied as the catalyst.…”