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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.

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.

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.