13, I~-tetra1riethyltricyclo [~.~. 2.~'~~ Jlie~~ deca-~,~~, l~~, l2, 13, l~-hesaerie). The latter dimer is derived from 1-methyl-3, 3, 6-triinethyletiecycloiene, presumably ilia t. he isotneric%,~-diiriethyl-pr~-ly! e~ ie The relative reactivities of the isomeric tetraene monomers are examined in niinbasic media. The significantly greater stability of 1, 2,~, 5- tetramethylenecyclohesa11e allows for il convenient preparation of its solutiotis from the ...