Synthesis of steroid–ferrocene conjugates of steroidal 17-carboxamides via a palladium-catalyzed aminocarbonylation – Copper-catalyzed azide–alkyne cycloaddition reaction sequence

[Display omitted] ► New ferrocene labeled steroidal 17-carboxamides were produced. ► The first step was the Pd-catalyzed carbonylation of steroids with 3-amino-1-propyne. ► The products underwent a facile azide–alkyne cycloaddition with ferrocenyl azides. ► Both reactions led to the products in good yields. ► The new compounds were characterized by various spectroscopic methods. Steroids with the 17-iodo-16-ene functionality were converted to ferrocene labeled steroidal 17-carboxamides via a two step reaction sequence. The first step involved the palladium-catalyzed aminocarbonylation of the alkenyl iodides with prop-2-yn-1-amine as the nucleophile in the presence of the Pd(OAc)2/PPh3 catalyst system. In the second step, the product N-(prop-2-ynyl)-carboxamides underwent a facile azide–alkyne cycloaddition with ferrocenyl azides in the presence of CuSO4/sodium ascorbate to produce the steroid–ferrocene conjugates. The new compounds were obtained in good yield and were characterized by 1H and 13C NMR, IR, MS and elemental analysis.