Three new trienes, ethyl 3-(2-vinylcyclohexenyl)-trans-propenoate (LO), ethyl 3-(2-trans- styrylcyclo-hexeny1)-trans-propenoate (1 l), and ethyl 3-[2-trans-@-methoxystyryl) cyclohexenyl]-trans-propenoate (14), have been prepared and characterized. The kinetics of the thermal electrocyclization of each was determined in an inert solvent. The results were as follows: 10, k (137" C)= 1.03 X 8, AH'= 109.6 kJ mol-', AS*=-58.6 J mol-K-'; 11, k (137" C ...
