Divergent synthesis of flavones and flavanones from 2'-hydroxydihydrochalcones palladium(ii)-catalyzed oxidative cyclization.

Divergent and versatile synthetic routes to flavones and flavanones efficient Pd(ii) catalysis are disclosed. These Pd(ii) catalyses expediently provide a variety of flavones and flavanones from 2'-hydroxydihydrochalcones as common intermediates, depending on oxidants and additives, discriminate oxidative cyclization sequences involving dehydrogenation, respectively, in a highly atom-economic manner.

Synthesis of Flavanones via Palladium(II)-Catalyzed One-Pot β-Arylation of Chromanones with Arylboronic Acids.

A total of 47 flavanones were expediently synthesized via one-pot β-arylation of chromanones, a class of simple ketones possessing chemically unactivated β sites, with arylboronic acids via tandem palladium(II) catalysis. This reaction provides a novel route to various flavanones, including natural products such as naringenin trimethyl ether, in yields up to 92%.