250712-77-7Relevant academic research and scientific papers
A synthesis of densely functionalized 2,3-dihydropyrans using ring-closing metathesis and base-induced rearrangements of dihydropyran oxides
Schmidt, Bernd,Wildemann, Holger
, p. 3145 - 3163 (2000)
The preparation of dihydropyran and dihydrofuran oxides and their rearrangement in the presence of lithium dialkylamides to functionalized 2,3-dihydropyrans or 2,3-dihydrofurans, respectively, is described. The regiochemical outcome of the reaction can be influenced by the relative configuration of the starting epoxides and the steric demand of the base. The 2,3-dihydropyrans obtained were converted stereoselectively to difunctionalized 3,4-dihydropyrans by the carbon-Ferrier reaction, or to fused acetals by addition of dimedone, mediated by ceric ammonium nitrate. The stereochemical results are rationalized by mechanistic proposals.
Epoxide opening reactions of aryl substituted dihydropyran oxides: Regio- And stereochemical studies directed towards deoxy-aryl-Cglycosides
Schmidt, Bernd
, p. 2627 - 2637 (2007/10/03)
2-Aryl-substituted tetrahydropyrans with 3,4- or 4,5-/ra;w-configured oxo substituents have been synthesized via ring-closing metathesis of allyl homoallyl ethers, epoxidation of the resulting dihydropyrans and opening of the epoxides with O-nucleophiles
