Molecular rearrangements in longipinane derivatives
Suitable oxygen substituted 2,6,6,9-tetramethyl- tricycle( 5.4.0. 02'8)undec-9-ene (longipinene) derivatives or their saturated analogues, which are both isolated as esters from nature, can be transformed to several new ring-system containing molecules, which include 4,8,8-tri- methyl-9-methyleneperhydro-ll5-methanonaphthaleneI 4,8,8- trimethyl-9-methylene-1,2,4a,5,6,7,8,8a-octahydro-ll5-meth anonaphthalene, 8,8,9-trimethy1-4-methy1eneperhydro-1,3,5- -methanonaphthalene, 2,6,6,11-tetramethyltricyclo(5.4.0. O4'*)undecane, 2, 6,6,9-tetramethyltricycl0(5.4.O.O~~~)un- decane and 4,4,8,9-tetramethylperhydro-1,7-methanonaph- thalene derivatives.