%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