Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... Efficient syntheses of 1,3-dimethy1-2-vinylbicyclo[4.1.0]hept-2-ene (1) and 2,2-ethylenedioxy-4,6-dimethyl-5-vinylbicyclo[4.1.0]hept-4-ene (2) are described. These dienes, which undergo Diels-Alder reactions with -benzoquinones readily, may serve as ...