Abstract: In a search for new estrogenic drugs, the 11-substituted estriols (11α-OH, 11α-OCH₃, 11β-OH, 11β-OCH₃ and 11β-OAc) were synthesised. A novel process for their preparations was described. The structure of synthetic compounds were confirmed by chemical transformation and spectral analysis. The hydroboration of the 9(11)-dehydroestrone-3-ether-17-ketal (3) and the enol acetates of 11-substituted estrone 3-ether (10a), (10b) were investigated. The by-products 17-ketalized 9α-hydroxy-estrone 3-ether (5) and 16-epi-11-substituted estriol 3-ether (13a), (13b) were obtained.