Arylation of lawsone through BF3-mediated coupling of its phenyliodonium ylide with activated arenes and aromatic aldehydes

Phenyliodonium ylide of lawsone, activated by BF3·Et2O, reacts with electron-rich arenes to afford the corresponding 2-aryl-3-hydroxy-1,4-naphthoquinones, in a coupling reaction without metal catalysts. The same type of products, in greater variety and higher yields, are obtained from the reaction of the BF3·Et2O-activated ylide with aromatic aldehydes in a synthetically and mechanistically interesting deformylation reaction.