Addition Oligomerization of Dicyclopentadiene: Reactivity of Endo and Exo Isomers and Postmodification. Issue 11 (21st March 2017) - Zanchin, Giorgia
Abstract : TiCl4 /Et2 AlCl is an active catalyst for the addition oligomerization of dicyclopentadiene. A crystalline tetramer is obtained from the endo dicyclopentadiene isomer which is less reactive than the exo isomer, while it exhibits a reactivity close to that of dihydrodicyclopentadiene. The postoligomerization modification through hydrogenation and epoxidation is explored and materials with tunable thermal properties are produced. Abstract : The oligomerization of dicyclopentadiene (DCPD, mixture of endo and exo isomers), 9, 10‐dihydrodicyclopentadiene (H‐DCPD), exo ‐DCPD, and endo ‐DCPD catalyzed by TiCl4 /Et2 AlCl is studied. Oligomers containing 2, 3‐enchained units are obtained in good yields. The endo ‐DCPD is less reactive than the exo isomer, exhibiting a reactivity comparable with that of the partially saturated H‐DCPD. While all the products obtained from the oligomerization of the exo isomer and H‐DCPD are amorphous, from the endo isomer, at low DCPD/Ti ratio, a crystalline, stereoregular tetramer having a 2, 3‐ exo ‐disyndiotactic structure is obtained. The results show that the presence of the double bond in the cyclopentene ring, the spatial disposition of the cyclopentene, and the oligomerization conditions play a fundamental role to give a unique crystalline material. Hydrogenation and epoxidation of the obtained products are reported as well.