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Heck reactions of some steroid derivatives possessing iodo-alkenyl moiety (17-iodo-androst-16-ene, 1, 17-iodo-4-aza-4-methyl-androst-16-en-3-one, 2, 17-iodo-4-aza-androst-16-en-3-one, 3) were carried out in the presence of palladium catalysts using various olefins (methyl acrylate, ethyl methacrylate, allyl alcohol and allyl acetate) as coupling partners. With methyl acrylate, a side reaction was observed: the coupling product underwent a Diels-Alder reaction with the excess of methyl acrylate resulting in a six-membered carbocyclic E-ring. Reaction conditions of the synthesis of the Heck-product were optimized. Although the coupling with allyl alcohol led to the formation of 21-formyl-16-pregnene derivatives, the synthesis of the corresponding steroidal unsaturated alcohol could be achieved only via hydrolysis of the coupling product of the alkenyl iodide with allyl acetate.

17-Iodo-delta 16 steroids undergo selective dimerization and carbonylative dimerization in the presence of palladium catalysts in dimethylformamide which result in 16-17'-coupled dienes and 17-carboxylic anhydrides, respectively. Moderate to good yields have been obtained for both types of dimers.

The palladium-catalyzed coupling of various 17-iodo-delta 16 steroids (17-iodo-androst-16-ene, 17-iodo-4-methyl-4-aza-androst-16-en-3-one, and 17-iodo-4-aza-androst-16-en-3-one) with dialkyl phosphites (dimethyl phosphite, diethyl phosphite, and diisopropyl phosphite) was examined in detail. The only successful condition for homogeneous coupling involved carrying out the reaction in the absence of any solvents. A large excess of dialkyl phosphite was used, which means that the phosphite itself acted as a solvent. Eight new androst-16-ene derivatives with phosphonate groups at C-17 were synthesized and characterized. These steroids are of pharmacological interest as potential 5 alpha-reductase inhibitors. Under the same conditions, methylation of lactam NH was observed using dimethyl phosphite.

Direct and carbonylative coupling reactions of various steroid derivatives possessing iodo- and bromo-alkenyl moiety (17-iodo-androst-16-ene, 1, 17-bromoandrost-2,16-diene, 2, 17-iodo-4-aza-4-methylandrost-16-en-3-one, 3, 17-iodo-4-azaandrost-16-en-3-one, 4) with vinyltributylstannane and ethynyltributylstannane were carried out in the presence of various palladium catalysts. While carbonylation took place only with vinyltributylstannane, 17-vinyl-, and 17-ethynyl-delta 16 steroids were produced via direct coupling with vinyltributylstannane and ethynyltributylstannane, respectively. Activities of some catalysts based on Pd(0) and Pd(II) precursors were compared, and Pd(PPh3)4 was found to be superior to other complexes in most cases. In the coupling of 17-iodoandrost-16-ene with organostannanes Pd2(dba)3 + 8 AsPh3 in situ catalyst was found to be even more effective.

The palladium-catalyzed vinylation of several steriod 2-enyl- and 3,5-dienyl-3 triflates and estrone-3-triflate was systematically examined using vinyltributylstannane as a vinylating agent. In carbon monoxide atmosphere the insertion of a CO molecule took place and unsaturated ketones were obtained. In this way new steroid derivatives containing unsaturated side chain were produced, which can serve as starting material for further functionalization of the steroid skeleton.