text: The total synthesis of galanthamine (Trost 2005)  is described as follows: the sequence starts by bromination by electrophilic aromatic substitution of isovanillin 1 to bromophenol 2, then by synthesis of the second intermediate 5 by reacting dialdehyde 3 in a coupled aldol reaction and Horner–Wadsworth–Emmons reaction with trimethyl phosphonoacetate 4. The hydroxyl group is activated as a trichloroethyl carbonate  leaving group to 6. Next an enantioselective Trost AAA reaction takes place between bromophenol 2 and carbonate 6 to the allyl ether 7.  Next the aldehyde group is protected as an acetal  in 8 and this step enables the organic reduction of the ester group to the alcohol 9 with DIBAH and subsequent homologation of this alcohol to a nitrile by Mitsunobu-type reaction using acetone cyanohydrine as the source of cyanide, to yield 10 followed by aldehyde deprotection to 11. The intramolecular Heck reaction to 12 forms the dihydrofuran ring. Allylic oxidation by selenium dioxide provides allylic alcohol 13 with the correct stereochemistry. The aldehyde reacts with methylamine to the imine 14 and reduction of the imine and nitrile by DIBAL-H leading to ring-closure to the aminal 15 (not isolated) followed by acid quenching gives the hemi-aminal 16. In the final step the hemiaminal is reduced to give Galanthamine 17 together with 6% of the epi isomer 18.