Cyclopropyl cyanide, when heated to 660-760K and under pressure of 2-89torr, becomes cis and trans crotonitrile and allyl cyanide molecules, with some presence of methacrylonitrile. This is an isomerization reaction that is homogeneous with rate of first order. The reaction result is due to the biradical mechanism,  which involves the formation of carbon radicals as the three carbon ring opens up. The radicals then react to yield carbon=carbon double bonds.