0000000000132177

AUTHOR

Hans-joachim Bissinger

showing 2 related works from this author

Preparation and reactivity of macrocyclic dienynes

2010

Abstract (1 E ,5 E )-Cyclopentadeca-1,5-dien-3-yne ( 1c ), which represents the first macrocyclic 1,5-dien-3-yne, can be obtained by thermal- or butyllithium-induced fragmentation of the corresponding 1,2,3-selenadiazole 8 . The ( E , E )-dienyne functionality causes a geometrical strain E g , which enhances the reactivity in addition ( 1c → 12 , 13 ) and cycloaddition ( 1c → 10 ) reactions and lowers the isomerization barrier to the unstrained ( E , Z )-configuration 1d ( E g  = 0). A slow process 1c → 1d occurs even at ambient temperatures within several weeks.

Fragmentation (mass spectrometry)Strain (chemistry)StereochemistryChemistryOrganic ChemistryDrug DiscoveryReactivity (chemistry)BiochemistryMedicinal chemistryIsomerizationCycloadditionTetrahedron Letters
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1-Cycloundecen-3-in

1988

Es wird ein Syntheseweg fur (E)-1-Cycloundecen-3-in (E-5) beschrieben (Schema 2). Die extrem gespannte Verbindung isomerisiert sich bei Raumtemperatur mit einer Halbwertszeit von 2.2 h (ΔG≠ = 76 kJ/mol). Durch Rotation um die CC-Doppelbindung entsteht dabei (Z)-1-Cycloundecen-3-in (Z-5), das keine geometrische Ringspannung Eg mehr besitzt.

chemistry.chemical_classificationCycloundecanoneKetoneHydrocarbonchemistryStereochemistryOrganic Chemistrychemistry.chemical_elementPhysical and Theoretical ChemistryMedicinal chemistryIsomerizationSeleniumLiebigs Annalen der Chemie
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