TY - JOUR A1 - Christl, Manfred A1 - Hegmann, J. A1 - Reuchlein, H. A1 - Peters, K. A1 - Peters, E.-M. A1 - Schnering, H. G. von T1 - Überbrückte neungliedrige α,β-ungesättigte Enollactone - Synthese aus 5-Phenyl-1,3,4-oxadiazin-6-on-2-carbonsäure-methylester und Konfigurationsanalyse N2 - The γ-oxoketenes, which are formed from oxadiazinone Ja and strained cyclopentene der1vat1ves, are shown to undergo a pericyclic ring enlargement to give the title compounds 2a, 2b, and 5. In the case of 5, two configurations, one having a cis and the other a trans Iactone functionality, are in equilibrium. KW - Organische Chemie Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58395 ER - TY - JOUR A1 - Hegmann, J. A1 - Christl, Manfred A1 - Peters, K. A1 - Peters, E.-M. A1 - Schnering, H. G. von T1 - Intramolekulare [2+2]-Cycloadditionen von γ-Oxoketenen N2 - The 1-oxoketenes, which are accessible from methyl 1,3,4-oxadiazin-6-one-2-carboxyIate 1 and cycloalkenes, are shown to undergo an intramolecular [2+2] cycloaddition either on heating or on photolysis to give different sterecisemers of ß-lactones of the 3-oxo-2-oxabicyclo[ 2.2.0]hexane-type. KW - Organische Chemie Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58384 ER -