The reductive cross-coupling of 1,3-dioxolane with carbonylcompounds to yield α-hydroxy aldehyde derivatives was attained by the reduction of iodobenzene with a solution of SmI2 in 1,3-dioxolane-CH3CN-HMPA (20:2:1) in the presence of carbonylcompounds under extremely mild conditions. The process seems to involve 1,3-dioxolanyl radical intermediate.
organic molecules with various ketones through sp3 C–H bond activation. The thiyl radical generated via single-electron oxidation of TPI by the excited photoredox catalyst abstracted a hydrogen atom from organic molecules such as toluene, benzyl alcohol, alkenes, aldehydes, and THF. The thus-generated carbon-centered radical species underwent addition to ketones and aldehydes. This intrinsically unfavorable
Gold‐catalyzed <i>endo</i>‐selective Ring‐opening of Epoxides and its Application in Construction of Poly‐ethers
作者:Kehuan Wu、Kaiwen Kang、Dan Liu、Chiyue Zhang、Xinyu Wang、Miaocheng Zhang、Qi Li
DOI:10.1002/chem.202400234
日期:2024.4.11
Abstract
Tetrahydropyran and tetrahydropyran‐fused poly‐ethers scaffolds are found in many classes of natural products and medicinally relevant small molecules. Here we describe a catalytic system for 6‐endo selective ring‐opening of epoxides by Au(I) or Au(III) catalyst that provides rapid access to various tetrahydropyran‐derived motifs. It also could efficiently construct the subunits of marine ladder‐like poly‐ethers through emulating the Nakanishi's hypothesis on the biosynthesis of these toxins. The synthetic utility of this method is also demonstrated in the preparation of the tricyclic core of tetrahydropyran‐containing macrolide natural products lituarines A−C.