%0 Generic %A Alcaide, Benito %A Almendros, Pedro %A Quirós, M. Teresa %A Lázaro, Carlos %A Torres, M. Rosario %D 2014 %T Three-Step Metal-Promoted Allene-Based Preparation of Bis(heterocyclic) Cyclophanes from Carbonyl Compounds %U https://acs.figshare.com/articles/dataset/Three_Step_Metal_Promoted_Allene_Based_Preparation_of_Bis_heterocyclic_Cyclophanes_from_Carbonyl_Compounds/2277526 %R 10.1021/jo500993x.s003 %2 https://acs.figshare.com/ndownloader/files/3913843 %K constants criteria %K carbonyl compounds %K bond %K method %K olefinic protons %K bi %K dihydrofuran moiety %K chemical shifts %K Carbonyl CompoundsA %K synthesis %X 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. %I ACS Publications