The synthesis of 17-alkoxycarbonyl- and 17-carboxamido-13α-estra-1,3,5(10),16-tetraene derivatives via palladium-catalyzed carbonylation reactions

17-Alkoxycarbonyl- and 17-carboxamido-13α-estra-1,3,5(10),16-tetraenes were synthesized from the 17-iodo-13α-estra-1,3,5(10),16-tetraene derivative in palladium-catalyzed alkoxycarbonylation and aminocarbonylation reactions, respectively. The synthesis of the 17-iodo-16-ene derivative, used as substrate, is based on the transformation of the 17-keto derivative (epiestrone methyl ether) to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). 17-Carboxamides were obtained in good yields (up to 88%) not only with simple alkyl/aryl amines but also with amino acid methyl esters as N-nucleophiles. The use of alcohols as O-nucleophiles in alkoxycarbonylation resulted in the corresponding 17-esters; however, yields of synthetic interest were obtained only with methanol.