in gas byproducts: hexabutylditin, Bu3Sn(CH3)CCHCH3; placing starting material in a porcelain cup in the sublimation chamber of a flash vac. thermolysis apparatus, react. at 800-850°C in the main oven and 250-300°C in the sublimation oven (10E-2 mm), oven packed with broken porcelain; vapors quenched on a dewar cold finger, pyrolysis tube cooled to room temp., product washed from the dewar surface (ether), ether evapd. chromy. (florisil); combined yield 42percent, terminal olefin 60percent, internal olefin Z/E 55/45 detd. by 13C-NMR;