17 tified on the basis of spectral data and elemental analyses. Irradiation with the Vycor filter for 65 hr produced the same amounts of products 5-12 that were produced in 130 hr with the Pyrex filter but the amount of polymer produced with the Vycor filter was about tenfold greater. The major reaction product, 4-methyl-3-cyalohexenyl methyl ketone (12), resulted from the thermal Diels-Alder addition of isoprene and 3-buten-2-0ne.'~ The yield of this ...
