Total Synthesis of (+)‐(2′S,3′R)‐Zoapatanol Exploiting the B‐Alkyl Suzuki Reaction and the Nucleophilic Potential of the Sulfinyl Group

Abstract

A stereoselective synthesis of the diterpenoid oxepane (+)-zoapatanol is described. The key steps include a B-alkyl Suzuki cross-coupling reaction for the stereoselective synthesis of trisubstituted alkenes, creation of the two stereogenic centers on the oxepane ring by heterofunctionalization of an alkene through substrate control exploiting the nucleophilic potential of an intramolecular sulfinyl group, and transformation of a β-hydroxy sulfoxide into a terminal alkene.

Aminooxylation Horner–Wadsworth–Emmons Sequence for the Synthesis of Enantioenriched γ-Functionalized Vinyl Sulfones

“…As shown in Scheme , ( R )- and ( S )- 16 engage in selective reductions. Magnesium(0) in the presence of catalytic amounts of Hg­(II) led to a reductive cleavage of the C–S bond to form ( R )- and ( S )- 18 in moderate yield . Use of typical hydrogenation conditions in order to generate a remote stereocenter provided ( R )- and ( S )- 19 in essentially quantitative yield .…”

Synthesis of 5‐[(Pentafluorosulfanyl)methyl]‐γ‐butyrolactones via a Silver‐Promoted Intramolecular Cyclization Reaction

“…The organic phases were combined, dried with MgSO 4 , filtered and concentrated in vacuo to afford the product (793 mg, 6.95 mmol, 99 %) as a colourless oil. Spectroscopic data were in accordance with the one described in the literature …”

Recent Applications in the Use of Sulfoxides as Chiral Auxiliaries for the Asymmetric Synthesis of Natural and Biologically Active Products

“…instance, in 2011, the Raghavan group completed the total synthesis of (+)-(2′S,3′R)-zoapatanol, 11 a diterpenoid oxepane from a Mexican plant, the zoapatle (Montanoa tomentosa) from which Mexican women prepare a 'tea' that induces menses and labor and terminates early pregnancy (Scheme 10). Thus, the -keto sulfoxide 52 was reacted with DiBAL-H to obtain diastereoselectively the corresponding alcohol, which was then protected as the silyl ether.…”