[Bibinou]

Hello,

it exists sevaral methods to make the flavone synthesis.
I see how works the fist step of each method, but don't see how works the mecanism of the other steps in both methods (see enclosed doc.)

I thank you very much for you help.

[Dan]

Methode 1, Ar = Aryl group

etape 2, enolise ketone, attack ester, leaving group is ArO^- (stabilised)
nucleophilic catalyisis by Pyridine?

etape 3, protonate rightmost carbonyl, attack with ArOH, dehydrate

Methode 2, etape2, I'm not sure of the role of glycerol here, sorry...

[Chudasama]

don't understand the source of base in methode 1 etape 3?

does dehydration proceed through a carbocation intermediate or a concerted mechanism?

could someone please kindly answer these questions

thanks