1347748-73-5Relevant academic research and scientific papers
Three-step metal-promoted allene-based preparation of Bis(heterocyclic) cyclophanes from carbonyl compounds
Alcaide, Benito,Almendros, Pedro,Quirós, M. Teresa,Lázaro, Carlos,Torres, M. Rosario
, p. 6244 - 6255 (2014)
A straightforward metal-mediated method for the synthesis of bis(dihydrofuryl) cyclophane scaffolds from carbonyl compounds has been developed. The combination of the dihydrofuran moiety with different heterocycles such as β-lactams and sugars allows high levels of skeletal diversity. The process comprises indium-promoted one-pot carbonyl bis(allenylation) and gold- or palladium-catalyzed double cyclization in the resulting bis(allenols), followed by selective ruthenium-catalyzed macrocyclization. In some cases, the method has been successfully applied to the synthesis of the challenging Z-isomers. The E- versus Z-stereochemistry of the metathesis-formed double bonds could not be assigned taking into consideration the usual coupling constants criteria, but a diagnostic based on the chemical shifts of the two olefinic protons located at the macrocyclic double bond was established.
