Polymerization of methylenecyclobutane

Coordination polymerization of methylenecyclobutane was first reported in 1969 by using Ziegler-Natta catalysts [152], and then other catalysts such as Ti(CH2Ph)4 and RhCl3 [153]. 

Marks reported ring-opening polymerization of methylenecyclopropane and methylenecyclobutane promoted by metallocenes of Zr and Lu. Cationic zirconocene complex initiates ring-opening polymerization of methylenecyclobutane to give a polymer having the =CH2 substituent on every fourth carbon of the polyethylene chain (Eq. 40) [154, 155]. Polymerization... 

Polymerization of Methylenecyclobutane. Methylenecyclobu-tane was synthesized by reaction of a Zn-Cu couple on pentaerytrityl tetrabromide (Equation 16). The yield of the synthesis is about 65% (9). 

Cationic Polymerization of Methylenecyclobutane. Attempts were made to discover catalyst systems able to attack methylenecyclobutane, and tests were carried out on different classes of catalysts. There was no detectable reaction when using either benzoyl peroxide, or anionic catalysts such as sodium naphthalene. However, interesting re-... 

---