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Ru-catalyzed cross-metathesis (CM) reaction between β-arylated α-methylidene-β-lactams and terminal olefins was developed. The CM reaction is effectively catalyzed with Hoveyda-Grubbs second-generation catalyst affording corresponding α-alkylidene-β-aryl-β-lactams in good isolated yields (41-83%) with exclusive Z-selectivity. The developed protocol was successfully applied for stereoselective preparation of Ezetimibe, the commercial cholesterol absorption inhibitor.

Synthesis of selectively substituted fluorenes and fluorenols was achieved by using catalytic [2+2+2]cyclotrimerization. Various starting diynes were reacted with different alkynes in the presence of a catalytic amount of Wilkinson's catalyst (RhCl(PPh3)3) providing the compounds possessing the fluorene scaffold in good isolated yields. A set of four regioselectively substituted fluorenols was converted to the corresponding 9,9'-spirobifluorenes and their spectral characteristics were measured.

We report a systematic study of the allylation of ortho-substituted benzaldehydes under catalysis of a Lewis base (N,N-dioxide), a Lewis acid (Keck allylation), and a Bronsted acid. ortho-Halobenzaldehydes were used as the aldehydic substrates, and special attention was paid to ortho-vinyl and alkynyl benzaldehydes, which might serve as interesting synthons for the preparation of more complex chiral compounds. Similar enantioselectivities were achieved under catalytic conditions. In the case of ortho-halobenzaldehydes, Lewis base catalysis proved to be more efficient, and the highest asymmetric induction for allylation of ortho-fluorobenzaldehyde reached 82 % ee, which is comparable to other used catalytic conditions. In cases of ortho-vinylbenzaldehyde, the Keck allylation provided the product in 88 % ee. An enantioenriched homoallylic alcohol was used as the starting material for the synthesis of a sertraline intermediate.

The enantioselective allylation of an aromatic aldehyde to give a chiral homoallylic alcohol was employed as the key step in the syntheses of a flobufen metabolite and dapoxetine. In the former case, the homoallylic alcohol moiety (99 % ee) was converted into a five-membered lactone ring with good preservation of the optical purity, and the target compound, a flobufen metabolite, was obtained in 95 % ee. In the latter case, the homoallylic alcohol moiety (97 % ee) was transformed over several steps into a 3-aminopropanol moiety. During the course of the synthesis, the gradual loss of optical purity was observed, and the target compound, dapoxetine, was obtained in 85 % ee.

Ferrocenestrone, the first steroid derivative containing a metallocene moiety, was stereoselectively prepared. The key steps included the enantioselective functionalization of ferrocene, elongation of the side chain, intramolecular enyne metathesis, Diels-Alder reaction, heterogeneous hydrogenation of the sterically hindered double bond, and finally inversion of the configuration at C13.

This short review aims to summarize recent advances in the use of transition-metal-catalyzed and -mediated methodology for the synthesis of steroid and steroid-like skeletons reported in the last decade. The methodologies used include transition-metal-catalyzed or -mediated [2+2+2] and other cycloadditions, the Pauson–Khand reaction, cross-coupling and Heck reactions, processes based on the activation of single and multiple bonds, metathesis reactions, hydrovinylation, and other reactions. Several examples of total synthesesof steroid compounds [e.g., (+)- and (–)-estrone, desogestrel] by these procedures are presented.

β-Anomeric derivatives react in a similar way with retention of configuration and E-selectivity in similar yields.

The asymmetric catalytic alkylation of ortho-substituted benzaldehydes proceeds under Lewis basic and acidic catalyst conditions to give homoallylic alcohols.

The enantioselective allylation of aldehydes (I) and (VIII) with pinacolborane (II) in the presence of a chiral BINOL-phosphoric-acid-derived catalyst is the key step in the synthesis of the flubofen metabolite (VII) and dapoxetine (X).

Pure anomers of either α or β 3-(2-deoxyribofuranosyl)propynoates reacted with the tetramethylcyclobutadiene–aluminum trichloride complex to yield the corresponding diastereoisomeric Dewar benzenes. Thermal- or ultraviolet light–initiated rearrangement gave rise to highly substituted C-aryldeoxyribosides as single anomers. The same compounds as well as other substituted deoxyribosides were obtained also by transition metal–mediated cycloaddition reactions.

This short review aims to summarize recent advances in the use of transition-metal-catalyzed and -mediated methodology for the synthesis of steroid and steroid-like skeletons reported in the last decade. The methodologies used include transition-metal-catalyzed or -mediated [2+2+2] and other cycloadditions, the Pauson–Khand reaction, cross-coupling and Heck reactions, processes based on the activation of single and multiple bonds, metathesis reactions, hydrovinylation, and other reactions. Several examples of total synthesesof steroid compounds [e.g., (+)- and (–)-estrone, desogestrel] by these procedures are presented.