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Reported herein is a stereoselective route to anti -β-hydroxy sulfoxides through the reaction of epoxides with sulfenate anions. Extensive experimental/computational studies revealed the dual special roles of MgBr2 ·OEt2 , serving to generate the bromohydrin alkoxide intermediate, which undergoes nucleophilic attack on the prochiral sulfenate in a diastereoselective manner. The present study has opened a general stereoselective synthetic route to anti -β-hydroxy sulfoxides. [ABSTRACT FROM AUTHOR]

A direct transformation of ortho‐alkynylated aromatic vinyl ethers to 1‐iodonaphthalenes and other iodo‐heterocycles under mild Lewis acidic conditions in the presence of iodide as an external nucleophile is reported. The first example of an iodoannulation strategy using a nucleophilic source of iodine, coupled with good to excellent yields, exclusive alpha regioselectivity and a broad substrate scope makes this work an attractive avenue towards the construction of aromatic iodides. Alpha wins the relay race: A direct transformation of ortho‐alkynylated aromatic vinyl ethers to 1‐iodonaphthalenes and other iodo‐heterocycles under mild Lewis acidic conditions in presence of iodide as an external nucleophilic source has been described. The first example of an iodoannulation strategy using a nucleophilic source of iodine, coupled with good to excellent yields, exclusive alpha regioselectivity, high scalability and a broad substrate scope makes this work an attractive avenue towards the construction of aromatic iodides. [ABSTRACT FROM AUTHOR]

We report here anenantioselective formal synthesis of vinigrolinvolving a 1–2–3 strategy: one pot and two reactionswith the formation of three rings leading to the core structure ofvinigrol from its stereochemically well-defined acyclic precursor. [ABSTRACT FROM AUTHOR]

The first total synthesis of parameritannin A2 (1), a branched epicatechin (EC) tetramer is reported. The "phloroglucinol trick" was used to circumvent two synthetic issues encountered when assembling four EC units, namely, the steric constraint and the formation of the C4-C6 interflavan linkage. As a substructure of the middle EC unit, phloroglucinol enabled the single-step assembly of two EC units (top and side) through A-type linkages. The middle EC unit was constructed by conducting a newly developed three-carbon flavan annulation via a Pummerer/Friedel-Crafts cascade reaction to furnish a trimeric intermediate bearing a thio-leaving group at C4 position, which allowed the final installation of the bottom EC unit., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A short and efficient approach to a 4-methylene-2-cyclohexenone substructure present in otteliones and loloanolides is described. This strategy involves a tandem enyne/ring closing metathesis as the key reaction to construct this labile core unit., (© 2011 American Chemical Society)