Synthesis of furan-bridged 10-membered rings through [8 + 2]-cycloaddition of dienylfurans and acetylenic esters.
[reaction: see text] The coupling of various dienylfurans with dimethyl acetylenedicarboxylate (DMAD) has been examined. In most cases this reaction proceeds via [8 + 2]-cycloaddition to afford furan-bridged 10-membered ring systems as a single diastereomer. Dienylfuran intermediates were generated using either a chromium carbene-based method or aldol-based methods. Reaction of [8 + 2]-cycloadducts with electrophilic reagents occurred selectively at the enol ether alkene.
Zhang
Lei
L
New Mexico State University, Department of Chemistry and Biochemistry, MSC 3C, Las Cruces, New Mexico 88003, USA.
Wang
Yu
Y
Buckingham
Clare
C
Herndon
James W
JW
D000114:Acetylene / Q000031:analogs & derivatives / Q000737:chemistry; D003500:Cyclization; D004952:Esters; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry*; D006572:Heterocyclic Compounds, Bridged-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure
D004952:Esters; D005663:Furans; D006572:Heterocyclic Compounds, Bridged-Ring; D000114:Acetylene