Total synthesis of linoxepin facilitated by a Ni-catalyzed tandem reductive cyclization

Abstract

A nickel-catalyzed reductive cyclization was developed to construct the tricyclic core embedded in linoxepin, a cyclolignan with a unique benzoxepin ring. The generated diasterodivergent acetals could be converted to the...

Recent Advances on the Development of Synthetic Strategies to Access Dibenzoxepine Derivatives

“…Finally, the compound 192 undergoes cyclization via Mizoroki-Heck reaction to afford linoxepin 165 in 57% yield (Scheme 63). [60] Template for SYNTHESIS Thieme…”

“…In 2022, Peng and co-workers developed a method for the total synthesis of (±)-linoxepin via Ni-catalyzed tandem reductive cyclization (Scheme 62). 60 Initially, olefin 186 was prepared from commercially available o-vanillin derivative 185 by a Wittig-hydrolysis-Wittig reaction sequence with the ylide generated from (methoxymethyl)triphenylphosphonium chloride to afford olefin 186 in two steps with an overall yield of 60%. Regioselective bromination followed by allyloxylation of the C=C bond of 186 with 2,4,4,6-tetrabromocyclohexa-2,5-dienone (TBCD) and allyl alcohol in DCM at 0 °C produced -bromo acetal 187 in 87% yield.…”

Photocatalytic Radical Cascade Dehalogenation/Carbo-cyclization/Sulfonylation Leading to Indole- and Benzofuran-Based Benzylic Sulfones

“…Recent advances in dehalogenation-carbon cycling have further broadened the use of this strategy . Presently, Heck cycloaddition of transition metal-catalyzed aryl halides with carbon–carbon multiple bonds is a widely used and mature technique for the synthesis of complex natural products and medicines . However, these reactions are limited due to stringent reaction conditions and elevated reaction temperatures.…”