An unprecedented C-C coupling reaction between alkenes and ketones by hydrogen-atom transfer, using Fe(acac) and PhSiH in EtOH, is described. This mild protocol features high site selectivity and allows the construction of sterically congested structures containing tertiary alcohols and quaternary centers. The overall process introduces a novel strategic bond disconnection for ring-closing reactions.

Herein, we present a dual catalytic strategy to efficiently obtain mono-protected homoallylic 1,2-diols by coupling abundant aldehydes with simple (silyl) enol ethers, thus providing direct access to this important motif without the (super)stoichiometric use of prefunctionalized metal-allyl species. The modularity of our approach is shown by the introduction of several silyl-and alkyl-based protecting groups, enabling a diverse protecting group strategy. To highlight functional group tolerance and chemoselectivity, we demonstrate the functionalization of a variety of aliphatic, aromatic and heteroaromatic aldehydes, even in presence of ketones and esters. The applicability was further supported by a large scale experiment and a robustness screening. Mechanistic studies support a radical mechanism, starting from the single electron oxidation of the silyl enol ether, facilitated by the β-silicon effect.

Iron-catalyzed hydrogen atom transfer-mediated intermolecular C-C coupling reactions between alkenes and tosylhydrazones, followed by in situ cleavage of the tosylhydrazine intermediates using Et3N, are described. The process involves a new strategic bond disconnection resulting in the reductive alkylation of non-activated alkenes. The reaction is operationally simple, proceeds under mild conditions, and has a wide substrate scope.

A novel methodology for the coupling of alkenes with aldehyde-or ketone-derived Cbzhydrazones to form a new CC bond through a radical process is described. The sequence comprises an initial in situ generation of an iron hydride followed by a hydrogen atom transfer to an alkene, a coupling with a hydrazone and a final reduction of the nitrogencentered radical. Hydrogenation of the obtained hydrazines renders amines, including valuable tert-alkyl amines.

The intermolecular reductive radical coupling of aldehydes with non-activated alkenes, employing metal hydride atom transfer (MHAT) catalysis with a combination of Fe II and Fe III salts, is described. This constitutes the first use of aldehydes as viable acceptor groups in MHAT reactions. The insights gained in this study led to the reexamination of the previously reported intramolecular version of the reaction, and the addition of Fe II salts allowed the development of a more efficient second-generation approach.

A formal total synthesis of the cytotoxic macrolide amphidinolide E is reported. The strategic steps are three Julia-Kocienski reactions (J-K), for the formation of the C5-C6, C9-C10, and C17-C18 double bonds, a Suzuki-Molander C21-C22 bond formation reaction, and a Kita-Trost macrolactonization. The "instability" of the two dienic systems and of the stereocenter at C2 (allylic methine, α to the carboxy group) and the protecting groups at C17-OH and C18-OH have posed difficult challenges. Each Julia-Kocienski olefination has been systematically optimized to provide the highest possible E/Z ratios.

An unprecedented C À Cc oupling reaction between alkenes and ketones by hydrogen-atom transfer,u sing Fe-(acac) 3 and PhSiH 3 in EtOH, is described. This mild protocol features high site selectivity and allows the construction of sterically congested structures containing tertiary alcohols and quaternary centers.T he overall process introduces an ovel strategic bond disconnection for ring-closing reactions.

From an (R)‐(+)‐pulegone‐derived building block that incorporates the stereo‐defined tertiary carbon bearing a methyl group, as found in the targeted sesquiterpenoid, a four‐step synthesis of (−)‐4‐epi‐presilphiperfolan‐8‐α‐ol was achieved. The key processes involved are a ring‐closing metathesis leading to a bridged alkene‐tethered ketone and its subsequent FeIII‐mediated metal‐hydride atom transfer (MHAT) transannular cyclization. This synthetic method, implying an irreversible addition of a carbon‐centered radical upon a ketone by means of a hydrogen atom transfer upon the alkoxy radical intermediate, was also applied in the synthesis of trans‐fused hydrindanols structurally related to botrydial compounds.