NORBORNADIENE PREPARATION METHOD Russian patent published in 2004 - IPC

FIELD: organic synthesis. SUBSTANCE: norbornadiene, or bicyclo[2.2.1] hepta-2,5-diene, which can be used in production of high- efficiency insecticides, resins, polymer materials, and also as base material for high-density, energy-rich and high- calorie fuels, is prepared by reaction of cyclopentadiene or dicyclopentadiene with acetylene in a continuous liquid-phase process in presence of solvent at 200-240 C and pressure above 25 atm, wherein cyclopentadiene-to- acetylene molar ratio is 1:(1-1.8) and solvent is preliminarily saturated with acetylene. Reaction mixture is then subjected to rectification to norbornadiene, whereas solvent is recycled. Method is characterized by using dimethylformamide or N-methylpyrrolidone as solvent and preliminary dissolution of dicyclopentadiene followed by saturation of resulting solution with acetylene at 15-20 C and atmospheric pressure. After that, reaction mixture is passed into reactor upwards and temperature of mixture coming out of the reactor is lowered to 20-30 C and pressure is lowered below its atmospheric value using for this damping damper-throttling device, top part of which receives nitrogen at pressure equal to that in norbornadiene synthesis unit. EFFECT: improved technology enabling implementation of the method in industrial scale. 1 dwg, 1 tbl, 12 ex